Sabtu, 30 Mei 2009

How Does Front-Wheel-Drive Work?

Description

    There are four-wheel-drive and all-wheel-drive vehicles that allow one to go off-road with their vehicles. However, not much is said about front-wheel-drive vehicles and how they function. Front-wheel-drive cars have become increasingly popular because they handle a little better in bad weather conditions. However, they do not perform as well in bad weather as a four-wheel or all-wheel vehicle can, but they do perform better than a rear-wheel-drive vehicle. The best description for front wheel drive is a defined as a vehicle in which only the front wheels are driven by the engine. Transverse engines are featured in most modern vehicles that have front-wheel drive. This means that instead of the longitudinal engines that most vehicles have, the front-wheel-drive vehicle has the transverse, or "sideways," engine under its hood.

Function

    Front-wheel drive works in the following way: An end-on mounted transmission, in conjunction with the transverse engine, uses drive shafts linked by CV joints, or constant velocity joints, to drive the front wheels of a vehicle. Because most of the engine's and transmission's power is being delivered to the front wheels, the car handles a little bit better than a rear-wheel drive vehicle would. Because of the way the front-wheel drive vehicle performs, many car manufacturers have stopped producing rear-wheel-drive vehicles and switched over to producing front-wheel-drive vehicles.

Past and Present

    The first documented front-wheel-drive vehicle is said by various sources to have been produced by Graf and Stift sometime between 1895 and 1898. During this time, they produced the De Dion-Bouton engine, which ran on one cylinder and powered the vehicle's front axle. In addition, the engine was located at the front of the vehicle. Fiat made front-wheel drive popular in 1969. Chevrolet was known for producing rear-wheel vehicles such as the Camaro and the Corvette, however, things changed and by the early 2000s, Chevrolet offered only one rear-wheel-drive vehicle, the Corvette.

How to Replace the Rotor in a Mercury Villager

If you notice that your Mercury Villager is starting to vibrate or pulse when you're coming to a stop, it's time to replace those old rotors. Your rotors are probably warped or worn down. You can have them tested and resurfaced, or you can install new rotors.

Instructions

    1

    Place a jack and jack stands under your Mercury Villager van and block the front and rear tires to keep your van from rolling.

    2

    Remove the wheel and tire assembly with a socket wrench or air wrench with an appropriate adapter. Remove the caliper bolt and slip the brake pad off of the old rotor. Support the caliper with a piece of mechanic's wire and then remove the old rotor.

    3

    Clean any debris and dirt and then replace the front disc brake with the new rotor and slide it into position. Secure the new rotor with holding screws and replace the brake caliper and pad and discard the wire.

    4

    Secure the caliper bolts to the correct torque (29 NM (22 lb/ft)). Replace the wheel and tire assembly and tighten the wheel bolts with a torque wrench.

How to Make Parking Brake Adjustments in a Nissan Pathfinder

Adjust the parking brake when your Nissan Pathfinder starts to slide down a hill with the parking brake activated. You can avoid going to the mechanic shop if you have a means to raise the rear wheels off the ground.

Instructions

    1

    Raise the rear of the Nissan Pathfinder with your jack and support the rear wheels with jack stands.

    2

    Pull up on the parking brake lever located in the center console of the vehicle.

    3

    Locate the parking brake lock nut attached to the parking brake cables and assembly. Crawl underneath the vehicle and find the assembly and cables mounted to the center drive shaft. Turn the lock nut with a wrench or pliers until the cables are loose.

    4

    Turn the adjuster lock nut until you have the correct amount of notches. Follow the guidelines of notches to pull up on depending on your Nissan Pathfinder year. Use 6 to 10 notches for years 1970 to 1983; use 13 to 16 notches for years 1984 to 1986; use 10 to 12 notches for years 1986 to 1988 and two-wheel drive; use nine to 11 notches for years 1986 to 1988 and four-wheel drive; for stick lever 1988 year models, use seven to nine notches.

    5

    Release the parking brake to the floor of the console. Spin the rear wheels to verify there is no resistance.

    6

    Lower your vehicle using the jack and remove the jack stands from the rear wheels.

How to Check Leaks for Power Brake Boosters

How to Check Leaks for Power Brake Boosters

The automobile's brake booster's main function is to give the vehicle maximum braking power with minimal pressure applied to the brake pedal. The brake booster primarily functions on the vacuum system of the vehicle. If the vacuum system is working properly, the booster pushes into the master cylinder when pressure is applied to the brake pedal, allowing the car to come to a stop. If there is an issue with the vacuum system, the car will still have brakes, but it will take a much greater effort on the pedal to stop the vehicle.

Instructions

    1

    Get into the car and start the engine. Without applying any pressure to the brake pedal, allow the car to idle for 60 seconds.

    2

    Turn the engine off after the one-minute idling time has passed, and allow the car to rest with the engine off for an additional minute.

    3

    Push on the brake pedal and release several times. If the vehicle's vacuum system is working properly, each push of the brake pedal should get harder to press to the floor. If there is a leak in the vacuum system, the pedal will continue to travel to the floor with no resistance.

How To Change the Brake Pads on a 2003 Jeep Liberty

How To Change the Brake Pads on a 2003 Jeep Liberty

The disc brake pads on your Jeep Liberty stop the Jeep while withstanding the high temperature generated from the friction involved in the braking process. There are many grades of brake pads, from organic pads to semi-metallic and even ceramic pads. The materials used in these different pad types react differently and fit different driving styles. Visit an auto parts store and talk with an associate at the parts counter to determine the right pads for your driving needs.

Instructions

    1

    Loosen the lug nuts on the front of your Jeep Liberty with a lug wrench but do not remove them from the wheel studs. Position a jack under the front suspension of the Jeep and raise the front end off the ground. Position a set of jack stands under the front suspension or frame rails of the Jeep and lower it until it is resting securely on the stands.

    2

    Remove the lug nuts from the wheel studs then remove the front wheels from the Jeep. Locate the brake caliper on the steering knuckle in front of you. Insert a pry bar between the rear pad and the rotor and carefully push the piston into the caliper. Be very careful not to damage the rotor. While Jeep recommends this method, it is not without risk.

    3

    Locate the two retaining bolts on the backside of the caliper. Jeep refers to these as the caliper slide mounting bolts because, as well as retaining the caliper, they allow it to slide in and out as pressure is applied to the system.

    4

    Remove the caliper slide mounting bolts from the caliper and mounting bracket with a socket and ratchet. The only access to the bolt heads is from the back of the caliper. Lift the caliper off the rotor and turn it on its back so the pads are facing up. Snap the outer pad out of the caliper, pulling it straight up and out.

    5

    Push the inner pad towards the center of the caliper, snapping the retaining clip out of the piston. Lift the pad out of the caliper and discard it. Verify that the caliper piston is pushed all the way into the caliper body.

    6

    Install a new inner pad on the caliper, snapping the retaining spring into the caliper piston. Install a new outer pad on the caliper, sliding the pad retaining clips onto the machined recesses in the caliper. Turn the caliper over and slide it back onto the rotor, aligning the mounting holes in the caliper with the holes in the mounting bracket.

    7

    Install the caliper slide mounting bolts in the holes and tighten them, until snug, with a socket and ratchet. Repeat the process on the opposite side of the Jeep, changing the pads on that caliper as well.

    8

    Install the wheels onto the wheel studs then install the lug nuts, tightening them, until they are snug, with a lug wrench. Raise the front of the Jeep with a jack, just off the jack stands. Remove the stands from under the Jeep then lower it to the ground.

    9

    Tighten the lug nuts with the lug wrench once the Jeep is securely on the ground. Before driving the Jeep, slowly pump the brake pedal several times to allow the caliper piston and inner brake pad to move out against the rotor. Test-drive the Jeep to ensure the brakes are working correctly and to seat the pads into the rotor.

Kamis, 28 Mei 2009

DIY Replacing Rear Brake Pads on an Acura

DIY Replacing Rear Brake Pads on an Acura

Replacing the rear brake pads on your Acura vehicle requires some specialty brake tools and a little mechanical know-how. It's a great way to educate yourself in the braking system for the vehicle, as well as saving yourself a bunch of money on labor charges that dealerships and repair stations will tack onto your repair bill. Brake pad sets are fairly inexpensive and the money you'll save on labor can be invested buying the tools you'll need to do the job.

Preparation

    Remove half the brake fluid from the master cylinder. Use a turkey baster or a hand pump to do this, but be careful not to get the fluid on the paint of the Acura. Brake fluid is highly toxic and will damage paint.

    Block one or both of the front wheels and make sure the parking brake is not applied. The rear calipers on Acuras integrate the parking brake system, so if it's applied, you will not be able to get the calipers off of the pads and rotors.

    Crack the lug nuts loose with a tire iron or suitable tool prior to lifting the Acura. A quarter turn is all that's necessary. Lift the rear of the Acura on a flat and hard surface and then support the vehicle on jack stands. Never use a jack as a support. Finish removing the lug nuts and then remove the wheels. Set the wheels out of the way so they do not interfere with your work area.

Replacing the Pads

    If applicable, remove the dust shield and then locate the two caliper guide bolts on the inside of the rear calipers. Perform the repair on one side at a time, so you can use the other as reference if necessary. Remove these bolts from the caliper using a ratchet and socket or a box-end wrench. You don't have to remove the parking brake cable if you're just replacing the brake pads. Next, pry the caliper off of the pads and rotor. Supporting the caliper to the rear suspension coil spring with a bungee cord or hook will prevent any damage from occurring to the rubber brake hose attached to it.

    Use a caliper reset tool to screw the piston in on the rear caliper. These tools can be rented as complete kits at most auto parts stores. They're also quite affordable to purchase. There are also even cheaper tools, like cubes that can be used in conjunction with a ratchet and extension.

    The rear calipers on Acuras feature two notches in the solid piston opposite one another. Find the correct adapter fitting on the reset tool that matches up to the notches and then use the clamp to screw the piston in clockwise until it bottoms out in the bore of the piston.

    Remove the old pads, shims and retaining spring and then clean off all the pad-to-caliper and caliper anchor contact points. Use a wire brush or something abrasive to do this. This will get rid of all the rust and corrosion on the hardware clips and caliper. Before installing the new pads, apply the shims if required. Lubricate the contact surfaces of the cleaned hardware and caliper. All sets of brake pads feature a small tube of lubricant, or you can purchase a higher quality lubricant inexpensively.

    Insert the new pads onto the lubricated hardware and then replace the caliper and caliper bolts.

Finishing the Job

    Once the Acura brake pads have been replaced, put the wheels and lug nuts back on. You won't be able to torque the lug nuts with the rear axle raised, so tighten the lug nuts snugly to hold the wheels secure. Raise the Acura to remove the jack stands and then slowly lower the vehicle back to the ground. At this point, you can torque the rear lug nuts with a torque wrench and a socket. Most all Acuras require about 80 foot pounds of torque for the lug nuts.

    Make sure the cover to the master cylinder is in place, then pump the foot brake pedal and apply the parking brake and then release it several times until the brake pedal feels firm. This will extend the pistons of the rear calipers outward so the pads will contact the rotors. Failure to perform this step will result in rear brake failure and a low brake pedal. Once the brake pedal is firm, recheck the master cylinder fluid and add new brake fluid to it (to the full mark), if necessary.

Selasa, 26 Mei 2009

How to Change the Front Rotors on a 1994 Geo Metro Car

How to Change the Front Rotors on a 1994 Geo Metro Car

The brake system of a 1994 Geo Metro consists of a set of brake pads that are pressed against metal discs, called rotors, to stop the vehicle. Overtime, the friction created can make the rotors too thin and they must be replaced. Geo provides minimum specifications for the front rotors, so determining when to replace them is easy. When fitted with a vented rotor, the minimum thickness is 0.590 inches; a solid rotor is 0.315 inches. Failure to comply with these minimum specifications may lead to additional brake damage, even complete brake failure.

Instructions

    1

    Place the Metro in park or reverse, depending if it's a manual or automatic transmission. Place the wheel chocks behind the rear wheels and set the parking brake.

    2

    Loosen the Metro's front lug nuts, but do not remove them.

    3

    Raise the front of the vehicle, with the floor jack, and secure it by placing jack stands beneath it. Make certain to position the jack stands under a solid component of the vehicle, the sub-frame -- directly below the engine -- is a good area. Lower the floor jack so the Metro's weight is solely on the jack stands.

    4

    Remove the front lug nuts and pull the wheels from the vehicle.

    5

    Remove the upper and lower caliper bolts, located on the rear of the caliper. Pull the caliper up and away from the brake rotor. Hang the brake caliper from a suspension component, using the bungee strap.

    6

    Remove the cotter pin, located on the shaft that protrudes from the caliper and hub, by straightening the "legs" on the end and pulling it out of the hole in the shaft. Loosen and remove the castle-nut -- nut with notches in the top -- from the shaft, using a ratchet and socket.

    7

    Loosen and remove the four bolts holding the hub to the brake rotor. Place the slide hammer on the wheel studs -- the bolts the lug nuts thread onto -- and hand-tighten lug nuts on the studs going through the slide hammer.

    8

    Remove the hub from the rotor by repeatedly sliding the hammer until the hub comes loose. Be careful not to place your fingers in the way of the slide hammer, this can cause a great deal of pain. Remove the slide hammer from the hub.

    9

    Pull the rotor from the vehicle. Place a thin coat of multi-purpose grease on the splines on the shaft.

    10

    Place the new rotor on the vehicle and place the hub on the rotor, make certain that the splines on the shaft line up with the notches in the hub. Tighten these bolts to 37 foot-pounds, using the torque wrench and a socket.

    11

    Install the castle-nut on the shaft and tighten it to 129 foot-pounds, using the torque wrench and a socket. Place the new cotter pin through a notch on the castle-nut and through the hole in the shaft. Bend the "legs" of the cotter pin in opposite directions to lock it into place.

    12

    Place the caliper on the new rotor and tighten the upper and lower bolts to 17 foot-pounds, using the torque wrench and a socket.

    13

    Repeat Steps 5 through 12 for the rotor on the other side.

    14

    Place the front wheels on the vehicle and hand-tighten the lug nuts.

    15

    Raise the Metro from the jack stands, using the floor jack. Remove the jack stands and lower the Metro to the ground.

    16

    Tighten the front lug nuts to 50 foot-pounds of, using the torque wrench and a socket.

How to Replace Back Brakes on Jeep Cherokees

How to Replace Back Brakes on Jeep Cherokees

Not only are squeaky or grinding brakes loud and embarrassing, but they can also be dangerous. The noise is a clear indication that you need to adjust, clean or most likely replace your brakes. Jeep Cherokees are equipped with drum brakes in the rear instead of disc brakes. These type of brakes differ from disc brakes due to the use of brakes shoes instead of brake pads. Drum brakes have many components, which requires a little more patience and special tools when replacing the rear drum brake shoes.

Instructions

Removal

    1

    Release the parking brake inside the vehicle. Loosen the lug nuts on each rear wheel using a tire iron. Raise the rear of the vehicle with a jack and support securely with jack stands. Place wheel chocks or bricks around the front tires to keep the vehicle from rolling forwards or backwards. Unscrew and remove the lug nuts using your fingers, remove the wheel and set aside.

    2

    Spray and air dry all drum brake components with brake cleaner. Do not used compressed air to remove brake dust or dry components.

    3

    Pull outward on the adjuster lever and turn the star wheel to retract the primary brake shoe. Pull on the self-adjuster cable, and push the adjusting lever toward the rear of vehicle, unhooking it from the secondary brake shoe.

    4

    Remove the primary shoe retracting spring using the shoe springs removal tool included in the repair kit. Lift and remove the self-adjusting cable and anchor pin plate from the anchor pin. Remove the secondary shoe retracting spring and self-adjusting cable guide using the shoe springs removal tool.

    5

    Remove the primary shoe hold-down spring and pin using the spring removal tool. Lift the primary shoe and adjusting screw from the backing plate and set aside. Using your fingers, pull and remove the parking brake link, making note of the small notch it is removed from.

    6

    Remove the secondary shoe hold-down spring and pin. Lift and remove the secondary shoe from the backing plate. Using a screwdriver, pry off the parking brake lever retaining clip from the pivot pin. Separate the lever from the secondary shoe with your fingers. There is a small washer located here that you can simply remove. Lubricate the brake shoe contact areas with high-temperature grease using the grease gun.

Installation

    7

    Lubricate anchor pins, support plates, self-adjusting cables, cable guides, screws, pivots and the parking-brake lever with high-temperature grease from the grease gun. Apply ample lubrication, but do not saturate.

    8

    Attach the new secondary shoe to the parking brake lever. Install the new spring washer and retaining clip on the pivot pin, then crimp the clip closed by squeezing together with the pliers. Install the secondary shoe and hold-down spring to the backing plate. Position the end of the parking brake link back into the small notch. Place the primary shoe against the backing plate. Install the hold-down spring. The parking brake strut and wheel cylinder pushrods will engage in the brake-shoe slots. Adjust with your fingers as needed to ensure they engage.

    9

    Install the anchor-pin plate and the self-adjusting cable. Hook on the open end of the secondary shoe retracting spring through the cable guide and into the hole in the shoe. Lightly pull and stretch the spring over to the anchor pin. Install the primary shoe retracting spring using the spring-installing tool.

    10

    Hook the adjusting lever spring into the hole at the bottom of the primary shoe. Hook the adjusting lever spring and cable into the adjusting lever, and pull the cable down and toward the rear of vehicle, inserting the hook on the lever into the hole on the secondary shoe. Insert a screwdriver or brake-adjusting tool through the adjustment hole, and turn the star wheel until the brakes drag lightly as the drum is turned. Turn the star wheel in the opposite direction until the drum turns freely. Keep the adjusting lever from contacting the star wheel by pushing on it with a screwdriver.

    11

    Mount the wheel, and hand tighten the lug nuts. Raise the vehicle off the jack stands with a car jack, remove the jack stands, and lower the vehicle to the ground. Tighten the lug nuts using a tire iron in a star pattern until all are tightened to torque specified in the owner's manual. Remove the heel chocks and perform numerous brake checks, checking for needed adjustments before driving in traffic.

Minggu, 24 Mei 2009

How to Troubleshoot ABS Brake Problems

How to Troubleshoot ABS Brake Problems

ABS brakes work with the braking system in a vehicle to help maintain control if there should be an emergency situation such as wet, slippery roads. Problems can occasionally occur with ABS brakes. Some of the signs that they are working correctly include a rapid pulsation of the brake pedal, or a slight vibration. If you are experiencing problems with your brakes, performing a few troubleshooting steps can help you to determine the issues.

Instructions

Methods of Troubleshooting ABS brakes

    1

    Put the key in the ignition and turn the car on and off, if the ABS light appears on the dashboard. This will sometimes solve the issues by resetting the code stored in the memory. If the problem persists, bring the vehicle to a mechanic shop where they will use a scan to connect with the ABS controller, which will locate and fix the code.

    2

    Clean the front wheel sensors if your ABS pulses at low speed while little pressure is applied. Bring the vehicle to a mechanic shop so that they can clean the sensors appropriately.

    3

    Apply pressure to the ABS brake if it won't stop. Check the master cylinder brake fluid to see if it is low, and fill it to the marked level if necessary. This may also mean that air is in the hydraulic system. Bleed the hydraulic system to resolve the issue.

    4

    Replace loose or broken front end parts if you experience a clunking noise while pressing the ABS brakes. Bring your vehicle to the nearest repair shop for service.

Sabtu, 23 Mei 2009

How to Adjust Emergency Brakes on a 1992 Grand Marquis

The rear brakes on your 1992 Grand Marquis are self-energizing servo-type drum brakes equipped with an automatic self-adjuster and auxiliary parking brake system. As the rear brake shoes wear, the distance between the shoes and the drum's friction surface increases. This along with stretching of the parking brake cables can cause the parking brake not to function properly. Adjustment of the parking brake is done in two stages, beginning with adjusting the brake shoes and ending with adjusting the cables to compensate for stretch.

Instructions

    1

    Release the parking brake and block the front wheels using wheel chocks placed behind the front tires. Raise and support the rear of the car with a floor jack placed under the center of the rear differential. Position the jack stands under the frame at the rear of the car and lower the Grand Marquis onto the stands to prevent accidents.

    2

    Slide under the rear of the car and locate the back side of the brake system backing plate to which the brake shoes are attached. Remove the small black plug located in the adjusting slot on the lower portion of the brake system backing plate by prying it out with a small screwdriver.

    3

    Insert a brake-adjusting spoon into the slot in the backing plate and rotate the adjuster wheel upward to adjust the clearance between the brake shoes and the drum. Rotate the wheel as you adjust the brakes. The shoes are properly adjusted when you feel a slight drag on the wheel caused by the shoes contacting the drum.

    4

    Apply the parking brake. If the parking brake fully engages after three to six clicks of the ratcheting mechanism, the parking brake is functioning properly. If the parking brake needs further adjustment, release the parking brake and adjust the parking brake cable.

    5

    Locate the parking brake cable adjuster by following the cable from the backing plate up toward the front of the Grand Marquis until you find the adjuster located on the driver's side frame rail. Loosen the 13-mm jamb nut on the adjuster with a wrench. Grasp the threaded cable end with a pair of pliers and turn the 13-mm adjuster nut until there is about 1 inch of travel when you pull down on the cable. Tighten the adjuster jamb nut.

How to Bleed ABS Brakes in a 1992 Chrysler T&C

Development of the Chrysler Town & Country began in 197, and the first Chrysler Town & Country was introduced in 1981. The 1992 Chrysler Town & Country was equipped with a 3.3-liter V-6, capable of producing 150-horsepower. The 1992 Town & Country was available in both front-wheel drive and all-wheel drive drivetrains. The 1992 Town & Country was equipped with four-wheel anti-lock brakes or ABS on all models, as a standard feature. ABS brake bleeding requires pressure to bleed the brakes, rather than gravity bleeding into a bottle.

Instructions

    1

    Park the vehicle on a solid, level concrete surface. Do not park on a incline, slope, gravel or asphalt. Open the hood on the Town & Country. Fill the brake fluid reservoir with DOT-3 or DOT-4 brake fluid. Place the brake fluid cap back onto the reservoir and lock it in place by hand.

    2

    Proceed to the driver's side of the minivan. Pump the brake pedal no less than 40 times. If you have no brake pressure at all after pumping five to 10 times, skip this step completely and proceed to Step 3. This procedure will release the ABS hydraulic accumulator pressure. When the brake pedal becomes stiff and difficult to depress, depress the pedal a few more times to release the pressure in the accumulator. You will notice a drop in the pedal pressure. Stop pumping the brakes.

    3

    Loosen the front wheel lug nuts, using a tire iron. Raise the front of the Town & Country with a jack. Place jack stands beneath the front subframe rails, just inward from the lower control arms. Lower the Town & Country onto the jack stands. Remove the front wheel lug nuts completely, then remove the wheel from the front of the minivan.

    4

    Loosen the rear wheel lug nuts, using a tire iron. Raise the rear of the minivan with a jack and place jack stands beneath the lower axle crossmember. Lower the van onto the jack stands. Remove the rear wheel lug nuts, then remove the rear wheels from the Town & Country. Spray the bleeder screws on the backing plate of the rear brakes, using PB Blaster, Liquid Wrench or CRC penetrating spray. Spray the front caliper bleeding screws, aiming the bottle inward toward the middle of the minivan. Allow the penetrating spray to set for at least 15 minutes.

    5

    Place your drain pan beneath the rear passenger drum brake assembly. Instruct your assistant to carefully sit in the driver's seat of the Town & Country and to depress the brake pedal as far down as it will go. Your assistant should follow the pedal to the floor with his foot and hold it until instructed to let go. Open the bleeder screw 3/4-turn with an open-end wrench. Allow the larger air pockets to exit the brake system along with some brake fluid. Close the bleeder screw snug. Tell your assistant to release the brake pedal.

    6

    Repeat Step 5 three times on both rear drum brake assemblies. This will remove any large pockets of air accumulated in the brake lines. Move the drain pan beneath the drum brake assembly that you are working on so you do not spill brake fluid on the ground. Proceed to the front of the van. Fill the brake fluid reservoir to the "Full" mark with fresh brake fluid. Install the reservoir cap and tighten it by hand.

    7

    Tell your assistant to depress the brake pedal, and hold it down until instructed otherwise. Place the drain pan under the front caliper. Open the bleeder screw on the passenger front caliper. Allow the large air pockets and some brake fluid to escape the front caliper. Tighten the bleeder screw snug with your open-end wrench. Instruct your assistant to release the brake pedal.

    8

    Repeat Step 7 three times on both front brake calipers to remove the large quantities of air from the lines. Move your drain pan beneath the caliper that you are bleeding. Refill the brake fluid reservoir after you complete this process on both front calipers. Install the reservoir lid and tighten it by hand.

    9

    Move the drain pan back to the passenger rear of the Town & Country. Instruct your assistant to pump the brake pedal five to 10 times, or until the pedal becomes stiff. Instruct your assistant to hold the pressure of his foot on the pedal and follow the pedal to the floor. Open the bleeder screw and release the remaining air from the rear brake line. Tighten the bleeder screw snug. Move to the front of the van and fill the brake fluid reservoir.

    10

    Repeat Step 9 on both rear brake drum assemblies three times, or until no air exits the lines. There is an audible hissing sound that escapes when there is still air in the system and you open the bleeder screw. Continue this bleeding process until no air or hissing sound is present when you open the bleeder screw. Refill your fluid reservoir after pressure bleeding each side.

    11

    Move to the front of the van with your drain pan. Instruct your assistant to pump the brake pedal five to 10 times, and then hold his foot on the pedal. Open the passenger front caliper bleeder with your open-end wrench. Allow the air and brake fluid to escape. Tighten the bleeder screw snug. Repeat this step three times on both sides of the van, or until no more air escapes when you open the bleeder.

    12

    Tell your assistant to pump the brake pedal five to 10 times to build pressure back up in the brake system. Instruct your assistant to release the brake pedal, then carefully exit the minivan. Refill the brake fluid reservoir and install the reservoir cap.

    13

    Install all of the wheels onto the Town & Country, and tighten the lug nuts snug with a tire iron. Raise the rear of the minivan off the jack stands, then remove the stands from beneath the minivan. Repeat this step to lower the front of the Town & Country to the ground. Immediately tighten all of the wheel lug nuts in a star pattern, using a 1/2-inch-drive torque wrench and wheel nut socket. The torque specifications for the 1992 Town & Country are 110 foot-pounds.

Jumat, 22 Mei 2009

What Happens if You Put New Pads on Bad Rotors?

What Happens if You Put New Pads on Bad Rotors?

Brake rotors need to be machined to correct distortion or damage to the braking surfaces. Restricted access to this service or field expediency may force the installation of new pads on bad rotors. Short-lived mobility may allow the avoidance of tow charges and permit the vehicle to reach a suitable repair location. This temporary repair method is not recommended. No reputable repair facility would engage in such activity, and many municipalities enforce legislation that prohibits ineffective or dangerous workmanship on brake systems.

Brake Pads

    Brake friction material is held to the pad backing plate in one of two ways. One method bonds the two substances with a strong adhesive, while the other style employs rivets to join the pieces. Either pad construction can severely damage the rotor if the friction material is worn away. The backing plates of bonded pads might contact the rotor somewhat evenly as material wears away. Riveted pads begin scoring grooves into the rotor as soon as friction surfaces wear down to the rivets.

In the Groove

    The deep grooves ground out of a rotor by pad rivets almost always ruin the part beyond repair. Similar marring from bonded pads render the same result. New pads only contact the highest surfaces of the rotors, greatly reducing stopping power. As new pads attempt to mate to the irregular surface, rough edges fracture the friction material. Material is quickly removed by the spinning rotor, much like the way a cheese grater cuts through a block of cheddar.

Hot Times

    Some brake rotors use finned vents to dispel heat
    Some brake rotors use finned vents to dispel heat

    Whatever damage occurs to a rotor, a side effect arises. Brakes generate and dissipate huge heat loads in normal operation. Malfunctioning parts or abusive driving habits can exaggerate the heat load beyond tolerances. The excess heat created by too much friction changes the metal of the rotor. Surfaces take on a blue color and do not respond to normal machining methods. Rotors exhibiting "hot spots" must be discarded.

The Skinny

    The braking surfaces of rotors are made in specific thicknesses. The needed value is determined by vehicle weight and horsepower as well as composition of materials used and construction design. Minimum thickness for any particular brake rotor usually is exceeded by all but the slightest marring. Metal is removed from the surfaces in the machining process, and no responsible technician will attempt to true a rotor too near the thickness limits for safe usage.

How to Change the Drum Brakes on a Ford Focus

The base model Ford Focus is equipped with rear drum brakes that provide about 20 percent of the braking force developed by the system. Over time, the brake shoes will wear, and this will cause a decrease in the rear brake functions like parking brake and brake pedal height. Replacing the rear shoes, and adjusting them properly, will restore parking brake function and brake pedal height. The average home mechanic can complete this repair in an afternoon, but no specialty tools are required.

Instructions

    1

    Block the front wheels with wheel chocks to prevent the car from rolling while the rear wheels are off. Raise the rear of the vehicle, using the floor jack, and place jack stands under the rear sub-frame. Lower the car onto the stands and roll the jack from under the Focus. Remove the lug nuts that attach the rear wheels to the axle and slide the rear wheels off the car.

    2

    Pry the dust cap, located in the center of the drum, out of the drum using a screwdriver. Remove the 32 mm axle nut using a socket and ratchet. Slide the drum off the axle and lay it aside. Place a drain pan under the brake system. Clean the brake system with brake-parts cleaner to prevent creating dust that can be harmful if inhaled.

    3

    Remove the clips that attach the brake shoes to the backing plate by depressing them with a screwdriver as you slide them off the hold-down pins. Pull back the spring on the parking brake cable and slide the cable from the parking brake lever that is attached to the rear-most shoe. Pull the brake shoes from the backing plate.

    4

    Squeeze the bottoms of the shoes together and remove the lower return spring. Remove the two return springs that attach the shoes to the adjuster mechanism and separate the shoes from the adjuster. Lubricate the sliding points on the backing plate.

    5

    Assemble the adjuster mechanism on the shoes and reinstall the return springs. Set the adjuster cam to its lowest setting. Position the assembly onto the backing plate and reattach the parking brake cable to the rear-most shoe. Install the retaining clips to attach the brake shoes to the backing plate.

    6

    Slide the brake drum onto the axle, and install the axle nut to 173 ft-lbs., using a torque wrench. Reinstall the rear wheels and lower the car from the stands. Test drive to verify that the brake system functions properly.

How to Replace a Caliper in a Nissan Sentra

Replacing a brake caliper in a Nissan Sentra, or any other vehicle, is a task not to be taken lightly. Such maintenance is best recommended for a trained mechanic. Should you look to replace a caliper yourself, consult such an expert before taking on such a job.

Instructions

    1

    Take the wheel off of the vehicle once it is securely raised on the jack stand. Use the "five-star" pattern to remove the lug nuts, removing the nut across from the one previously removed.

    2

    Disconnect and plug the brake hose from the caliper, discarding the washers on the bolt. Remove the parking brake cable and the lock spring if it's a rear caliper. Remove the caliper pin bolts.

    3

    Remove the caliper, pivoting it upward away from the rotor and sliding it off the pin sleeve. Remove the pads, shims and pad springs.

    4

    Install the replacement caliper with new pads, new shims and the pad retainers. Torque the pin bolts to 16 foot pounds to 23 foot pounds.

    5

    Connect the hose with new washers, tightening the flare nut to 12 foot pounds to 14 foot pounds. Connect the lock spring and the parking brake cable back onto a rear caliper.

    6

    Bleed the brake system by opening the bleeder valve and having another person depress the pedal to remove air. (Use a clear vinyl tube on the valve.) Top off the master cylinder afterward if needed.

    7

    Reattach the wheel and lower the vehicle. Test the brakes for firmness. Don't do so on the road until after they feel firm while stopped.

How to Replace Drums on a 1991 Jeep Wrangler

How to Replace Drums on a 1991 Jeep Wrangler

The drums on the rear brakes of the 1991 Jeep Wrangler (also produced as the the YJ Wrangler from 1987 through 1995) may have two different types of connecting applications. While the procedure to remove the drums is quite similar, there is one major difference to be aware of. Removing the drums is necessary to inspect and/or replace the rear brake shoes or the rear wheel brake cylinders. Disassembling the rear brake drums is also required if you are replacing the rear axle seals.

Instructions

    1

    Place a wheel chock in front of one the front tires of the 1991 Jeep Wrangler after it's parked on a flat, paved surface. Do not apply the parking brake, or the rear shoes will contact the rear drums and prevent the drums from being removed. Make sure the Wrangler is in park or in first gear.

    2

    Raise the rear quarters of the Wrangler one at a time with a jack. Place a jack stand under each side of the rear axle.

    3

    Remove the lug nuts and the rear wheels.

    4

    Spray penetrating oil around the rear lug studs and the center hub mating surface to the drum. Also spray oil on the three retaining screws, if applicable. Wait several minutes to allow the oil to penetrate.

    5

    Inspect the studs of the Wrangler to determine if the drum is held on by small retaining rings, if applicable. If so, use a pair of channel locks or cutting dikes to remove and discard the rings. They are not needed for removing and replacing the drums. They hold the drum in place.

    6

    Remove the three retaining screws from the hub facing of the drum, if applicable, using the impact screwdriver, a Phillips-head bit and the hammer. Place the bit and driver in the head of the screw, turn the impact driver counterclockwise and strike the head of the driver with the hammer. Repeat for each screw.

    7

    Strike the hub facing of the drum to break it loose from the hub connection. Try to pull the drum off. If the drum is stuck on the shoes from a rust ridge, proceed to Step 8.

    8

    Remove the small, black rubber plug at the bottom of the backing plate behind the drum. Insert the small, thin-bladed screwdriver into the port the plug was removed from and locate the starwheel adjuster retaining clip. Depress the clip inward through the port and use the brake adjusting tool/spoon to de-adjust the brake shoes inward away from the shoes. Turn the cogs of the starwheel downward with the tool/spoon a few turns. Attempt to remove the drum again. Continue this procedure until the drum comes off the rear brake shoe assembly.

    9

    Spray the inside and the outside of the replacement drums with brake/parts cleaner spray. Wipe the spray off with a shop rag.

    10

    Install the drums onto the rear brake shoe assembly. Adjust the brake shoe outward using the small thin-bladed screwdriver and brake adjusting tool/spoon. Turn the wheel upward to extend the shoes outward until there is a slight drag on the rear wheel when rotating the drum clockwise.

    11

    Replace the wheels and lug nuts. Tighten the nuts in a star pattern snug to the hubs using the lug wrench.

    12

    Raise the Wrangler above the jack stands. Remove the stands and lower the vehicle to the ground. Retighten the lug nuts with the torque ratchet and the 3/4-inch socket, again using a star pattern.

Kamis, 21 Mei 2009

Acura Brake Problems

Acura Brake Problems

Most Acura models are equipped with power assisted brake systems that are hydraulically operated. All front brake systems are disc brakes. The rear brakes can be either disc or drum, depending upon the model type. However, before assuming that a brake problem exists, ensure the tires are in good condition and properly inflated, the front end alignment is correct and the vehicle is not loaded with unnecessary weight.

Vehicle Pulling

    If your vehicle pulls to one side while braking, it could be related to one of the following brake problems: Restricted brake lines or hoses, malfunctioning drum brake or caliper assembly, loose suspension parts, loose calipers or excessive wear of brake shoe or pad material or disc/drum on one side.

Noises

    If a high-pitched noise, such as a squeal, is heard when the brakes are applied, the front disc brake pads are most likely worn out. The noise comes from the wear sensor rubbing against the disc and the brake pads should be replaced as soon as possible. If a chattering or rough noise is heard while braking, it could be related to excessive lateral run out, uneven brake pad wear or defective discs.

Excessive pedal effort or travel

    When applying the brake, a number of problems can lead to excessive pedal effort being required to stop. These problems include malfunctioning power brake boosters, partial brake system failure, or excessively worn brake pads or shoes. If new pads or shoes were recently installed, it may take awhile for them to be seated against the disc or drum. The piston in caliper or wheel cylinder could also be stuck or sluggish; or the brake pads and shoes are contaminated with excess oil or grease. If the brake pedal travel is excessive, you could be dealing with a brake system failure, insufficient fluid in the master cylinder or air trapped in the brake system.

Dragging or grabbing brakes

    If you find that your brakes are dragging, it could be related to an incorrect adjustment of the brake light switch, restricted brake lines or hoses or an incorrect parking brake adjustment. Another cause may be that the master cylinder pistons are not returning to the home position correctly. If you find that the brakes are grabbing or unevenly braking, then your Acura could have a malfunctioning proportioning valve or power brake booster unit. In addition, you could have a binding brake pedal mechanism leading to the grabbing.

Spongy or low resistance braking

    Another braking problem that may be experienced with your Acura is a spongy brake when it is depressed. This is generally caused by air in the hydraulic lines, a defective master cylinder or loose mounting bolts in the master cylinder. If there is little resistance when braking, or the brake pedal travels to the floor, it could be related to the fluid level in the master cylinder reservoir caused by a leaking caliper piston. It could also be related to loose, damaged or disconnected brake lines.

How to Change Rear Brakes on a Celica

The Toyota Celica was manufactured with rear drum brakes, which require replacement or resurfacing of the friction surfaces at regular intervals. The drum cylinders and twin curved shoes use up their friction material, and can be maintained by the average backyard mechanic in about an hour.

Instructions

    1

    Raise the Celica at the rear frame rail, just in front of the brake to be changed. Position the floor jack under the rail and pump the lever until the wheel is in the air. Place the jack stand head under the frame rail.

    2

    Remove the wheel by turning the lug nuts counterclockwise, then pulling the wheel from the hub. Store the wheel away from the work area.

    3

    Remove the rear drum by turning the keeper screw counterclockwise, then pulling the drum from the brake assembly. The drum will slide off, away from the backing plate.

    4

    Use the screwdriver to lever the long springs off the shoe hooks. The springs can be changed for new units, or left dangling for reuse.

    5

    Turn the primary spring bolts counterclockwise and slide the shoes directly away from the brake assembly.

    6

    Replace the shoes and slide them into position onto the brake assembly. Tighten the primary spring bolt in the center of each shoe, then lever the long springs back onto the shoe hooks. Check the adjustment bolt at the bottom for slippage, and check the wheel cylinder for leaks.

    7

    Replace the drum with a new or resurfaced unit by sliding it over the shoes and pressing it to the backing plate. Replace the keeper screw by turning it clockwise until it is tight.

    8

    Replace the wheel by turning the lug nuts clockwise, in an alternating pattern.

    9

    Lower the car from the jack stand with the floor jack.

    10

    Repeat the process on the opposite side.

Mazda Millenia Brake Rotor Removal

The Mazda Millenia uses a hydraulic caliper to apply friction to a brake rotor, stopping the vehicle. This rotor can wear out or become damaged from debris or lack of maintenance. As the rotor begins to degrade, the surface can warp or fracture, and could be potentially dangerous. The average backyard mechanic can remove a brake rotor in about 20 minutes.

Access

    The rotor is an integral part of the braking system, but it is embedded behind other components. By lifting the Mazda at the frame rail and removing the wheel, access to the brake is possible. Inspect the assembly for damage and debris. The rotor should feel smooth and have a silver, shiny appearance. Pitted or rusty rotors are a sign of poor maintenance.

Caliper

    The caliper has two bolts on the rear of the housing that attach them to the brake assembly. Turning them counterclockwise will release them, and you can slide the caliper off the rotor disk. Remove the caliper's pads by gently prying them loose with a screwdriver. But secure the caliper to the control arm of the car or tie it up so you don't damage the brake line to which it is attached.

    Some pros will clamp the caliper pistons to ensure easy replacement of the caliper, as they will expand when removed. On heavy-duty vehicles with large calipers, this could be a problem; but the Mazda's caliper pistons are not difficult to press back in.

Removal

    Once the caliper is off, the rotor will pull directly away from the hub. Thoroughly inspect it for damage, and measure it for thickness. Turning the rotors is the economical way to replace the unit; but if you resurface them without enough material, they could warp or become a hazard. Change the pads when you change the rotors, so they can "mate" together. If you use old pads, the lifespan of the new rotor will be diminished, and the car may not stop as well as it could.

Selasa, 19 Mei 2009

Ceramic Brake Pads Vs. Semi-Metallic

Ceramic Brake Pads Vs. Semi-Metallic

The braking system is one of the most important parts of an automobile. Brakes are integral to vehicle safety as well as performance. Like most vehicle systems, brakes also require occasional service, including the replacement of brake pads, which wear down with use. While most new cars come with semi-metallic brake pads, other types of pads are available from aftermarket auto manufacturers that may work better for certain drivers.

History

    For decades few decisions were made when choosing replacement brake pads. Semi-metallic and asbestos-based pads were used interchangeably and performed in a similar way. As health concerns led to a decline in the use of asbestos pads, newer materials, including ceramic, were used instead. The appearance of ceramic brake pads as a common aftermarket option began in the 1990s. Today several different types of ceramic pads are available, along with a range of semi-metallic and other options.

Construction

    Semi-metallic brake pads are composed of various metal bits, along with a bonding material to hold the pieces together and give the brake pad its structure. The metals used can include anything from steel wool to bits of metal wire and iron dust. Graphite and copper are also commonly used. In general, semi-metallic pads contain between 30 and 65 percent metal. So-called low-metallic pads are similar but use less metal in their construction. Ceramic brake pads are made mostly of ceramic fibers and may also contain a small amount of metal.

Use

    Ceramic and semi-metallic brake pads are used in the same way once inserted into a car's braking system. Brake pads are used on disc brakes, which use the pads to squeeze a spinning disc rotor. The pads are attached to a caliper that closes as the brake pedal is depressed inside the car. The pads produce friction and intense heat by rubbing against the spinning disc, thus slowing or stopping the car. Over time the pads wear down and become brake dust which coats the inside of the wheel or is discharged onto the road. Once they wear down enough, the pads must be replaced.

Advantages

    Ceramic and semi-metallic brake pads have certain advantages over other types of pads. Semi-metallic pads are inexpensive and provide excellent transfer of heat away from the rotor. This helps prevent against warping of the rotor, which can occur when the rotor is overheated. In addition, semi-metallic brake pads are hard and wear down slowly. Ceramic brake pads are softer and so put less wear on the rotor's surface. They are also quiet and are good at producing smooth friction for consistent stopping.

Disadvantages

    Both types of brake pads also have certain disadvantages. Ceramic pads are more expensive and, because they are so soft, wear down more quickly. They also subject the rotor to more heat. Semi-metallic pads may wear down the rotor itself more quickly, requiring it to eventually be replaced. They can also be noisy, since they contain metal shards that will come into contact with the rotor once they are exposed on the surface of the brake pad. This will produce noise until either the metal shard in the pad, or the rotor itself, wears down sufficiently.

How to Replace the Front Brakes on a 1997 Mazda Protg

The front brakes on the Mazda Protg are easy to replace. You can expect it to take you about 30 minutes to replace the brake on each wheel. When you are replacing the brake pads, it is a good time to inspect the brake rotors for surface damage. Any grooves or other damage on the rotors will need your attention. You can complete this project in your driveway, saving you from paying the labor costs at a repair shop.

Instructions

    1

    Place the Mazda on a level surface and turn off the key. Open the engine compartment and drain half of the brake fluid from the brake master cylinder using the turkey baster. Place the fluid in the drain pan for proper recycling later. The master cylinder is at the back of the engine compartment on the driver's side.

    2

    Place the wheel chocks behind the rear wheels of the Protg. Raise the car up with the jack. Place a jack stand under the Mazda and raise it to the frame of the car. Remove the lug nuts from the wheel with the lug wrench. Pull the wheel off the car.

    3

    Loosen the bolts on the brake caliper with a socket and ratchet and pull it from the mounting bracket. Place the caliper and the back brake pad into the jaws of the C-clamp and turn the handle until the jaws of the C-clamp push the caliper piston back into the caliper housing. Remove the brake pads from the caliper.

    4

    Place a new set of brake pads into the caliper. Put the caliper on the mounting bracket and tighten the bolts with the socket and ratchet. Put the wheel on the car and tighten the lug nuts with the lug wrench. Remove the jack stand from under the Mazda. Lower the car to the ground. Repeat the process on the other wheel.

    5

    Add fresh brake fluid to the master cylinder as needed when both wheels are complete. Pump the brakes several times until the pedal feels firm. This will seat the brake pads against the brake rotor. Check the brake fluid to see if you need to add more to the master cylinder. Never add fluid above the "Max" line.

Senin, 18 Mei 2009

How Do I Install Front Brake Pads in a 2002 Honda Accord?

How Do I Install Front Brake Pads in a 2002 Honda Accord?

The front brakes do most of the stopping on a vehicle. Therefore, they wear out the fastest. The front brake pads on the 2002 Honda Accord are equipped with wear indicators. These are small pieces of metal on the brake pads that contact the rotor when the pads are worn. When you start to hear a high-pitched chirping or squealing sound coming from the front brakes, it is time to replace the pads. If ignored, the brake pads will wear out, resulting in the metal backing cutting into the rotors, requiring them to be replaced.

Instructions

Front Brake Pad Removal

    1

    Loosen, but do not remove, the lug nuts with a lug wrench. Raise the front of the vehicle with a jack. Place jack stands under each front door at the lift points.

    2

    Remove the lug nuts and the front wheels. Remove the lower brake caliper bolt with a 17 mm wrench. Rotate the caliper upwards.

    3

    Slide the brake pads out of the caliper bracket. Insert the screw of a large C-clamp into the caliper piston and slowly tighten it to retract the piston until it stops.

Front Brake Pad Installation

    4

    Slide the new brake pads into the caliper bracket. Position the new brake pads with the wear indicators on the inside of the rotor at the bottom.

    5

    Rotate the caliper back into position. Install and tighten the caliper bolt. Replace the wheels and hand-tighten the lug nuts. Lower the Accord and tighten the lug nuts with a lug wrench.

    6

    Check the brake fluid reservoir and add brake fluid as necessary to reach the "MAX" mark. Pump the brake pedal several times to extend the caliper piston and seat the brake pads against the rotors.

Minggu, 17 Mei 2009

How to Remove the Front Brake Rotors on a 1994 Mazda Protege

In 1990, Mazda released a new entry-level sedan to its lineup, the Protege. The original Protege featured hard body lines and a somewhat boxy appearance. In 1994 -- the final year before Mazda redesigned the Protege -- the entry-level sedan came standard with a 103-horsepower, 1.8-liter four-cylinder engine. A set of ventilated disc brakes had the responsibility for bringing the Protege to a halt. Over time, or due to excessive pad wear, the brake rotor can become too thin to be safe and requires replacement. The Protege has a slightly unorthodox rotor removal process, but not more difficult than other and more common rotor replacements.

Instructions

    1

    Open the Protege's hood, and unscrew the cap from the master cylinder reservoir. Siphon about half of the brake fluid from the master cylinder using a clean turkey baster. Transfer this fluid to a small container.

    2

    Loosen the front lug nuts using a ratchet and socket. Raise the front of the Protege off the ground using a floor jack. Slide jack stands under the Mazda's subframe, and lower the vehicle onto the jack stands. Remove the lug nuts and pull the front wheels from the vehicle..

    3

    Look on the front part of the caliper and find the brake pad access hole on the caliper. Find the "W" spring on the outermost part of the brake pad access hole. Pull the "W" spring from the holes in the two pad-retaining pins.

    4

    Pull the two pad-retaining pins from the caliper using needle-nose pliers. Squeeze the "M" spring -- the M-shaped metal spring -- on the inside of the brake pad access hole, and pull the spring from the brake pads and caliper. Slide the brake pads out of the caliper through the brake pad access hole.

    5

    Remove the two caliper-retaining bolts using a ratchet and socket, and pull the caliper off the steering knuckle. Set the inner pad inside the caliper, so it contacts the caliper piston. Position an 8-inch C-clamp over the caliper, so the fixed part of the clamp touches the rear of the caliper and the screw part touches the brake pad. Tighten the C-clamp until the brake pad stops moving. Loosen the C-clamp and remove it from the caliper.

    6

    Remove the rotor retaining screw using a Phillips screwdriver -- if the screw doesn't turn, lightly tap its head with a hammer to free it first. Grab the rotor, and pull it off the Protege's hub. If the rotor does not pull off easily, lightly strike the rear of it with a rubber mallet to free it.

    7

    Set a new rotor on the Protege's hub, lining up the screw hole on the rotor with that on the hub. Tighten the rotor retaining screw with a Phillips screwdriver.

    8

    Set the caliper back on the Protege's front steering knuckle and hand-tighten the caliper-retaining bolts. Tighten the caliper-retaining bolts from 29 to 36 foot-pounds using a torque wrench and a socket.

    9

    Slide new brake pads through the brake pad access hole on the caliper. Squeeze the "M" spring, and line up the ears of the "M" spring in the hole in the top center of both brake pads. Slowly release the "M" spring until the ears insert into the holes.

    10

    Slide the pad retaining pins through the holes in the caliper, through the holes in the brake pads and through the hooked part of the "M" spring. Rotate the pad retaining pins until the small holes on the outside part of the pins face the brake pad access hole in the caliper.

    11

    Insert each end of the "W" spring into the holes on the outside of the pad retaining pins -- you may need to rotate the pins slightly to line up the pins with the holes.

    12

    Repeat Steps 3 through 11 to replace the brake pads on the other side of the Protege.

    13

    Set the wheels back on the Protege's front hubs and hand-tighten the lug nuts. Raise the Protege off the jack stands using a floor jack, and remove the jack stands. Lower the Mazda to the ground. Tighten the lug nuts from 65 to 87 foot-pounds -- in a crisscrossing pattern -- using a torque wrench and socket.

    14

    Press and release the brake pedal repeatedly until it feels firm. Check the brake fluid level in the master cylinder reservoir. Add DOT 3 brake fluid until the fluid level reaches the "Max" line on the reservoir. Tighten the master cylinder lid onto the master cylinder reservoir.

    15

    Take the container of old brake fluid to an automotive fluid recycling center. Some auto parts stores take old brake fluid free of charge.

Jumat, 15 Mei 2009

What Are Some Signs That May Indicate a Problem With Your Brake System?

What Are Some Signs That May Indicate a Problem With Your Brake System?

A car's brakes are essential to its operation and your safety. Knowing what signs indicate brake trouble early on can save you hundreds of dollars, and may even save the lives of you and your loved ones. There are several telltale signs that a car may be having brake trouble. This article will help you identify some of them.

Squeaky Brakes

    When your brakes start to emit a high-pitched whining or grinding sound, it's likely that your car needs repairs. It could be something as simple as the brakes wearing down, or something much more serious. Which is why it's important to get it checked out by a technician or mechanic.

Pulling

    If your car starts to pull to one side or another, this can indicate several problems, including a sticking caliper, worn disc hardware, a bad brake hose, misadjusted brakes or low tire pressure. Be sure to check your tires. If that's not the problem, it may be important to bring your car to a mechanic.

Shaking or Vibration

    If your car's steering column or brake peddle or the car itself starts to shake, this can be a sign of unevenly worn brake rotors or drums, and signifies that they need to be changed.

Brake Light

    Perhaps the most obvious indication of a brake problem is the brake light. If your brake light is on, take your car to a mechanic immediately. Your brake light could indicate that your brakes are vulnerable to failure.

Low Peddle

    If your peddle nearly touches the floor before the brakes kick in, you could have a problem. This could indicate something as minor as needing a brake adjustment, or could mean that parts of your brake systems are failing.

Hard Peddle

    A peddle that is difficult to push down may indicate damaged brake linings, power brake trouble or other problems.

ABS Light

    If the anti-lock brakes light is on, it could mean anything from low brake fluid to a failing component, and thus can indicate a problem that is very minor or very serious, or anywhere in between. Luckily, the ABS light only governs your anti-lock braking system. Even if the ABS light is on, your brakes will still work.

Grab

    If your brakes grab, even with light touches, this may indicate that something is loose in your brake system. It could also mean that you have something like grease or oil contamination in your brake lines.

Kamis, 14 Mei 2009

How to Make Parking Brake Adjustments in a Pontiac Grand Am

Adjust your Pontiac Grand Am parking brake easily using a pliers. Get underneath the car to make this simple adjustment. Save yourself time and money doing the adjustment at home instead of taking your car to the mechanic shop. Make the adjustment when your car starts to slip down the hill when parked on a slope. Use this technique for Pontiac Grand Am years 1985 through 1993 and 1999 to 2005.

Instructions

Years 1985 to 1993

    1

    Pull up on the parking brake lever by hand until it clicks three times. Locate the parking brake lever inside the vehicle between the driver seat and the front passenger seat.

    2

    Raise up your Pontiac Grand Am rear wheels. Use your jack and support the rear wheels with the jack stands.

    3

    Locate the parking brake cables underneath the car, coming from both rear wheels. They are coated wire cables. Spray the cables with penetrating oil. This prevents damage to the cable and to the adjuster nut.

    4

    Use your pliers to hold the braking cable and use another pliers to adjust the nut. Test the adjustment and spin the rear wheels around. Keep adjusting the nut until you can just spin the rear wheels backward and not spin them at all forwards.

    5

    Take off the parking brake and test the wheels for full rotation backwards and forwards. Lower your Pontiac Grand Am using the jack and removing the jack stands.

Years 1999 to 2005

    6

    Apply and release the parking brake five times. Verify the parking brake lever releases completely by turning on the ignition of your car and verifying the parking brake light does not turn on.

    7

    Pull up on the parking lever to four clicks. Raise your cars rear wheels with a jack and and support the wheels with the jack stands. Verify the rear wheels cannot be turned.

    8

    Release the parking brake and verify the wheels can spin freely. Lower your car using the jack and remove the jack stands.

Rabu, 13 Mei 2009

How to Replace Brake Pads on a Ford Ranger

How to Replace Brake Pads on a Ford Ranger

Ford Rangers, like any other car or truck, need to have their brake pads changed regularly. Ford Rangers use the same brake pad system as the Ford Explorer and failure to maintain them results in compromising the function of the brake system, and therefore increases the potential for accidents and harm to yourself, your passengers and to strangers. Fortunately, brake pads can be changed at home. Learn how to do so on your Ford Ranger and keep your brake system up to date.

Instructions

    1

    Remove the hubcap from the wheel, if your Ranger has a hubcap, and loosen the front-wheel lug nuts with the lug nut wrench before you lift up the Ranger. Simply crack the nuts so they can be hand-loosened once the ranger is lifted.

    2

    Lift the Ford Ranger, using the jack. Lift one side at a time so you can change the pads one side at a time.

    3

    Position the large-sized C clamp over the top of the calipers so the clamp is placed right up against the inside section of the caliper housing. Make sure the screw drive part of the clamp is also tight against the outboard pad. Next, tighten the clamp so that the clamp squeezes the pistons of the caliper directly into the bores. If your Ranger has dual-piston calipers, as most do, squeezing one piston to its full extent will suffice in order to compress the other one as you can only position the clamp against one of the pistons.

    4

    Find both of the caliper retaining bolts located on the inside edge of the caliper and remove them. Use the ratchet and socket to remove both of the bolts.

    5

    Remove the caliper as the pistons are now compressed, which makes for easy removal of the calipers. Use the metal coat hanger and bend it to concoct a makeshift hanger that will support the caliper in conjunction with the shock bracket.

    6

    Pry out the old pads with a screwdriver. Pry them out from the caliper bracket that is covering the rotor. You may not need the screwdriver if the pads are loose enough.

    7

    Position the shims so they are installed on the back of the backing plate of the pads. The shim kits you purchase come with some aftermarket pads and may require you to peel off the plastic wrap before applying the shim to the pad. Once the shims are positioned, install the pads into the caliper bracket.

    8

    Reposition the caliper over the newly installed pads and the rotor. Wipe clean the retaining bolts, using a clean rag and apply a layer of anti-seize compound onto the smooth portion of the bolt. Be careful not to use any of the anti-seize on the bolt's threads. Slide the bolts into the caliper first with your hand and then tighten them using a ratchet and socket.

    9

    Put the wheel back onto the car and screw in the wheel nuts. Tighten the wheel nuts so they are secure before lowering the truck. Once the truck is lowered, finish the job by re-tightening the nuts, using the lug nut wrench. Repeat the same steps for the other side of the car.

Selasa, 12 Mei 2009

How to Replace the Front Rotor on an RX330

How to Replace the Front Rotor on an RX330

The front brake rotors on the Lexus RX330 model vehicles are the main component that the front brakes compress against to stop the vehicle. The front rotors on the Lexus RX330 are also vented to allow the heat to escape from the brake rotors. This venting design on the front brake rotors helps prevent warping and cracking from extreme heat. Once the front rotors start to crack and warp, the rotors will need to be replaced.

Instructions

    1

    Park the Lexus RX330 in the area that you are going to be working in and set the emergency brake.

    2

    Open the hood and remove the cap from the brake fluid reservoir.

    3

    Loosen all of the lug nuts on the front driver side of the Lexus RX330 with the lug wrench.

    4

    Jack the front of the Lexus RX330 up and put a jack stand under each frame rail behind each front tire. Lower the jack so that the Lexus RX330 is resting evenly on the jack stands.

    5

    Finish unscrewing the lug nuts from the lugs and pull the wheel off the hub. Set the wheel to the side.

    6

    Locate the brake caliper that is sitting on top of the brake rotor. Take the pry bar and stick it between the rear brake pad and the brake rotor. Pry the rear brake pad toward the back side of the brake caliper. This will compress the cylinder inside of the brake caliper enough for you to be able to swivel the brake caliper.

    7

    Remove the lower, caliper-mounting bolt on the rear of the caliper with the 1/2-inch breaker bar and a socket. The brake caliper on the Lexus RX330 has a bolt on the rear bottom of the caliper and a swivel pin on the top of the caliper. Once you remove the bottom bolt from the rear of the caliper, swivel the caliper upward. Put the bungee cord on one end of the caliper and hang the other end of the bungee cord on the frame rail. This will give you the room needed to remove the brake rotor from the hub.

    8

    Remove the Allen-head bolt that is holding the brake rotor in place. The Allen-head bolt is on the facing of the brake rotor. Insert the Allen wrench inside of the Allen head bolt and turn the Allen wrench counterclockwise to loosen and remove the bolt.

    9

    Slide the old brake rotor straight off of the hub. Set the rotor to the side and slide the new brake rotor onto the hub. Screw the Allen-head bolt back into the facing of the rotor and tighten the Allen-head bolt down tight with the Allen-head wrench.

    10

    Unhook the bungee cord and slide the brake caliper back over the new brake rotor. Screw the rear bottom-mounting bolt back into the caliper. Tighten the rear-caliper bolt down tight with the 1/2-inch drive breaker bar and a socket.

    11

    Slide the wheel back onto the hub. Screw the lug nuts on and tighten them down with the lug wrench. Then, jack the Lexus RX330 up and remove the jack stands. Lower the Lexus to the floor.

    12

    Finish tightening the lug nuts down tight with the lug wrench. Screw the cap back onto the brake fluid reservoir. Follow these same steps for replacing the brake rotor on the front passenger side also.

How to Replace the Rear Brakes on a 1992 Toyota Camry XLE

How to Replace the Rear Brakes on a 1992 Toyota Camry XLE

The Camry XLE used disc brakes at the rear wheels as well as at the front wheels, providing added stopping power as well as added safety, especially when used in conjunction with the anti-lock braking system. The rear brakes tend to last longer than those at the front, due to the majority of the vehicle's weight being transferred to the front during stops, but this does not mean they should be neglected.

Instructions

    1

    Park the Camry on a flat, level surface. Open the hood and disconnect the negative battery cable to prevent shock and unintended operation of the vehicle.

    2

    Use the lug wrench to loosen the lug nuts on the wheel. Leave the lug nuts on the wheel and raise the rear of the vehicle with a floor jack. Support the vehicle with jack stands. Finish removing the lug nuts with the lug wrench and set the lug nuts aside for safe keeping. Grasp the wheel with both hands and pull it off of the hub to reveal the brake hardware.

    3

    Locate the two bolts holding the caliper to the mounting bracket and remove them with a ratchet and socket. Slide the caliper off of the brake rotor and suspend it from a coil spring or other suspension component with mechanic's wire. Remove the brake pads from the caliper bracket.

    4

    Place one of the old brake pads against the piston inside of the caliper and place a C-clamp between it and the back of the caliper. Use the C-clamp to push the piston back inside of the caliper housing.

    5

    Insert the new brake pads onto the mounting bracket. Place the caliper over the pads and the rotor. Reinsert the two retaining bolts into the back of the caliper and tighten them with the ratchet and socket.

    6

    Replace the brakes on the other wheel as outlined in the above steps. When finished, mount the wheel onto the hub and reinsert the lug nuts onto the studs, hand-tightening them before lowering the vehicle. Remove the jack stands from underneath the vehicle and use the floor jack to lower it safely to the ground.

    7

    Tighten the lug nuts with the lug wrench. Reconnect the negative battery cable and close the hood. Make sure to press the brake pedal four to five times so the pads are properly set in position.

Senin, 11 Mei 2009

Corvette Brake Problems

Corvette Brake Problems

The brake system of the Corvette is complex, but armed with the right information you can easily identify and troubleshoot any system problems yourself, regardless of the year of your Corvette. Be sure to exercise the utmost caution and use systematic procedures when troubleshooting your Corvette at home. The most common problem is a relay, but this guide will help prepare and educate yourself for any problems you may have to fix.


Brake System

    The Corvette brake system has exponentially improved over the years, employing technology that performs without failure or safety risks. But even with the recent release of stronger and bigger carbon ceramic brakes, any car requires maintenance and paying close attention for any irregularities in the driving performance. The pedal pulsating and a distinct whirring sound are all good indicators there is something wrong with the brake system, no matter what year Corvette you own.

Getting Familiar with the Brake System

    If your ABS light is on, this signifies that the fuses should be checked. If the 10-amp gauge fuse and the 10-amp brake fuse look fine, the modulator assembly will need to be checked as well. If your Corvette is a convertible, the speaker assembly will have to be manually removed to get to the module.

    The relay named PN 1636973 is the most common problem with the brake system. There are several ways you can test these at home if preferred. Identify the numbers on the pins and use this as reference for the wire colors you may need to troubleshoot in the future.

A Test Light

    A test light can be used when turning the key to make sure there is voltage at pin numbers 87 (orange), 15 (black/pink) and 30 (orange/black). The relay is works fine if there is voltage detected for all three of these. If there is no voltage detected, the connector lead to the relay may not have a sound connection.

    The ground also needs to be checked by testing for voltage on pin 31. As a ground for the relay, no voltage should be detected. The test light will illuminate if there is a bad ground. The ground further on the wire needs to be tested for proper contact. The test light will illuminate on both sides if there is a bad ground further still.

Solenoid and Pump Motor

    If the relay module is working properly, the relays operating the solenoid and pump motor, both of which are located on the top of the pump, could be the source of the problem. Because the relays connect directly to the pump, putting new relays in is a quick fix. Another option is the removal of the control module connector and checking the voltage after the relay for pin position 9.

Other Options

    This guide should successfully identify any problems with the brake system. If all these tests don't isolate the problem, the high amperage circuit should be checked for power. If that is running properly as well, it may be time to let a licensed mechanic take it from here.

How to Change the Brake Pads for a 1997 Plymouth Grand Voyager

How to Change the Brake Pads for a 1997 Plymouth Grand Voyager

The 1997 Plymouth Grand Voyager uses front disc brake pads and can sometimes feature rear disc brake pads. While rear drum brakes are more common on this vehicle, replacing the front and/or rear brake pads employs the same procedure. Like its cousin, the Dodge Grand Caravan, the brake pads on these minivans are clipped to the caliper housing. The outer pad clips to the outer housing with spring clips, while the inner pad uses a spring clip the sits inside the hollow caliper piston. These clips are riveted to the backing plates of the pads.

Instructions

    1

    Wedge a tire blocking device behind one of the rear wheels if replacing front brake pads or in front of one of the front wheels if replacing rear brake pads.

    2

    Apply the parking brake if replacing the front brake pads, and release the primary hood release latch inside the Grand Voyager.

    3

    Release the secondary hood release latch, open the hood and support it on the hood prop rod. Remove the master cylinder cap and use the clean suction syringe to remove half of the brake fluid. Dispose of the fluid, and replace the cap.

    4

    Crack the wheel nuts loose on the two tires of the axle on which you're replacing the pads using the tire lug wrench to turn the nuts one-half turn counter-clockwise.

    5

    Lift with a jack each front or rear quarter panel high enough to support the minivan safely and securely onto jack stands and then remove the wheel nuts and tires.

    6

    Remove the inner caliper mounting screws with the ratchet and a compatible socket. Pry the caliper off of the rotor using a pry tool, and then use the pliable, sturdy wire to tie the caliper to the front or rear chassis. This will alleviate damage from occurring to the rubber brake hose line attached to the caliper.

    7

    Unseat the clips of the outside pad from the caliper housing using the pry tool to release the clips off of the outer caliper housing.

    8

    Insert the caliper piston compression clamp to the inner outside housing of the caliper and the compression screw placed against the face of the inside pad. Tighten the clamp in a clockwise motion to compress the piston fully into the caliper piston bore.

    9

    Remove the inside brake pad from the caliper piston bore by pulling upward on it and releasing the retaining clip from the steel plate of the pad.

    10

    Insert the inside brake pad and retaining clip into the caliper piston first, and then pry the outside brake pad clips onto the outer caliper housing.

    11

    Replace the caliper and pads over the brake rotor, and replace the caliper mounting bolts. Hand-thread the bolts to avoid cross-threading them. Tighten them with the ratchet and a compatible socket.

    12

    Replace the wheels and wheel nuts. Tighten the wheel nuts employing a star pattern with the tire lug wrench until the nuts are seated against the hub tightly, and then lower the minivan to the ground. Use the 100-foot lb. torque wrench with a 3/4-inch or 19-mm socket to re-tighten the lug nuts, again employing the star pattern.

    13

    Pump the brake pedal until it feels firm, and then check the brake fluid level in the master cylinder. If necessary, fill the master cylinder with brake fluid, release the parking brake, if applicable, and then remove the tire blocking device before test driving the Grand Voyager.

Minggu, 10 Mei 2009

How to Remove Old Ford Brake Drums

Older model Ford vehicles use brake drums on the rear axle (models built before the late 1960s may also have brake drums on the front axle). A brake drum system works by mounting a large steel or cast iron drum on the axle shaft. The brake shoe are mounted inside this drum. When the driver depresses the brake pedal, a hydraulic cylinder inside the brake drum pushes the two brake shoes outward, where they contact the brake drum. This slows the vehicle down.

Instructions

    1

    Raise the rear of the vehicle using an automotive jack and support with jack stands placed underneath the rear axle.

    2

    Use a lug wrench or impact socket to remove the lug nuts from the rear wheels.

    3

    Pull the wheel and tire assembly off the lug studs.

    4

    Remove the brake drum, by pulling it off the lug studs.

Sabtu, 09 Mei 2009

How to Replace Drum Brakes on a GMC Truck

Drum brakes on GMC trucks are found on the rear wheels of modern models while older trucks may have drums on both the front and the rear wheels. Drum brakes are more difficult to replace than disc brakes. When replacing drum brakes, you change out the shoes in the drum brake.

Instructions

    1

    Park the vehicle on a level surface and turn off its ignition. Set the two wheel chocks in front of the two front wheels. Loosen the wheel's lug nuts using the tire iron, turning counterclockwise. Raise the rear end of your truck with the jack and set the jack stands under both sides of the rear axle. Lower your truck onto the stands with the jack. Remove the lug nuts on your rear wheels with the tire iron. Slide the rear wheels off the the truck and pull the brake drum off the hub.

    2

    Locate the adjuster spring on the top half of the brake assembly. Remove the spring with the pliers and detach the retractor spring that links the shoes.

    3

    Slide out the rear-facing shoe manually, along with the adjuster lever and the assembly for the adjuster screw. Remove the parking lever from the brake shoe. Move the retractor spring to the side and remove the forward-facing shoe. Repeat the Steps 1 through 3 for the remaining wheel(s).

    4

    Insert new brake shoes into both drums and reverse the instructions you followed above to restore all of the drum brake components to their original positions. Slide the drum back onto the wheel.

    5

    Twist the star wheel on the adjuster screw clockwise with a flat-head screwdriver to tighten it and gain enough clearance for the drum to go over the shoes. Replace the vehicle's wheels and tighten the lug nuts by hand, turning clockwise. Lower your truck with the jack and remove the jack stands. Tighten the lug nuts with the tire iron.

Jumat, 08 Mei 2009

How to Replace Rear Drum Brakes With Disc Brakes

Most all of the newer make and model vehicles come with front and rear disc brakes, but there are some vehicles that do come equipped with drum brakes. The drum brakes can be converted to disc brakes so that the vehicle will have a four wheel disc braking system. The disc brakes are designed to stop the vehicle by applying friction to the sides of the brake rotor when the brake pedal is compressed. The drum brake to disc brake conversion will prevent from having to use two different types of braking components.

Instructions

    1

    Park the vehicle on a level surface and shut the engine off. Slide the wheel chocks in the front of both front wheels and behind both front wheels.

    2

    Loosen the lug nuts on both rear wheels about one-quarter of a turn counterclockwise with a tire tool. Jack the rear of the vehicle up and place the jack stands under the designated rear jacking points on both sides of the vehicle. Lower the vehicle onto the stands and leave the jack in place.

    3

    Remove all of the lug nuts from the rear wheels. Pull the wheels off and place them flat down near each work area. Move to the driver's side rear brake drum and pull it off with your hands. If the drum is stuck, use a rubber mallet to tap the drum off of the brake shoes. Place the drum on the ground.

    4

    Remove the upper springs from the brake shoes with the brake shoe spring removal tool. Remove the retainer clips from the front sides of each brake shoe. Reach inside of the brake shoes and pull the retainer springs off of the retainers. Slide the parking brake cable off of the anchor pin. Pull the brake shoes apart and off of the spindle backing plate. Discard the brake shoes. Pull the brake shoe star adjuster wheel off of the bottom of the backing plate. Loosen and remove the brake line from the back of the backing plate with a open end wrench.

    5

    Remove the contents from the disc brake conversion kit to ensure that all of the braking components are there. Pull the rotor bearing out of the kit and secure it inside of the brake rotor. Slide the brake rotor onto the spindle and completely up against the backing plate. Secure the rotor to the backing plate with the brake rotor mounting bolts. The bolts screw into the back side of the rotor and the back side of the backing plate.

    6

    Remove the brake caliper assembly and the brake pads from the disc brake conversion kit. Insert the two new disc brake pads into the brake caliper. Slide the caliper assembly over the brake rotor. Screw the mounting bolts through the back of the backing plate and through the caliper bracket. Tighten the caliper bracket bolts with a ratchet and a socket. Clip the parking brake cable onto the designated area on the back of the brake caliper. Screw the brake line into the rear of the caliper. Tighten the brake line with a open end wrench. Screw the two upper and lower caliper mounting bolts through the back of the caliper and into the caliper bracket. Tighten the caliper mounting bolts with a ratchet and a socket.

    7

    Torque the caliper bracket mounting bolts to 50 foot-pounds and the caliper mounting bolts to 35 foot-pounds with a torque wrench and a socket. Torque the brake rotor mounting bolts to 100 foot-pounds with the torque wrench and a socket. Inspect the new disc braking components to ensure that all of the components are in place and properly tightened. Slide the wheel onto the hub and screw the lug nuts on tightly. Move to the passenger's side rear wheel and repeat the same process as outlined above to convert the drum brakes to disc brakes.

    8

    Jack the rear of the vehicle back up and remove the jack stands. Lower the vehicle to the ground and remove the jack. Finish tightening the lug nuts down tight on both rear wheels. Crank the engine and pump the brake pedal in and out five or six times to position the disc brake pads to the proper distance from the brake rotor.

Kamis, 07 Mei 2009

How to Install Disc Brake Calipers

How to Install Disc Brake Calipers

Installing disc brake calipers is basically the same for all vehicles, including the front and back calipers. When you put a new caliper on an automobile, you also have to put a new brake hose on as well. Changing a caliper does not take very long. You can get the job done in about 30 minutes for each wheel. Changing the calipers yourself can save you a great deal of money since labor rates at the auto repair shop tends to be on the high side.

Instructions

    1

    Place a pair of wheel chocks behind the rear wheels of the vehicle. Raise the automobile on the side that you are starting with using the automobile jack. Place a jack stand under the vehicle near the jacking point and raise it to the frame. Remove the lug nuts with the lug wrench and take the wheel off the vehicle.

    2

    Loosen the retaining pins on the back of the brake caliper using a socket and ratchet. Lift the caliper away from the mounting cradle. Disconnect the brake hose from the caliper using a wrench. Disconnect the hose from the main brake line using the wrench.

    3

    Connect the new brake hose to the main brake line and tighten it with a wrench. Connect the brake hose to the caliper and tighten it with the wrench. Insert the brake pads into the caliper along with any shims that are required. Place the caliper on the mounting cradle and tighten the retaining pins with the socket and ratchet.

    4

    Install the wheel on the vehicle and tighten the lug nuts with the lug wrench. Remove the jack stand from under the vehicle. Lower the automobile to the ground. Repeat the procedure on the other wheel.

How to Replace Brake Pads on a Ford Explorer

How to Replace Brake Pads on a Ford Explorer

The Ford Explorer brake pads, along with the calipers and rotors, ride behind the wheels, mounted to the axle hubs. When you push on the brake pedal, hydraulic fluid forces the caliper to push the brake pads onto the rotor from both sides. This action stops the Explorer but also wears down the pads. While the front pads wear out roughly twice as often as the rear pads, sooner or later the Explorer will need a rear brake job. Replacing the rear brake pads is a task anyone with basic auto repair skills can accomplish in about two hours.

Instructions

    1

    Place the wheel chocks tightly up against the front tires so the Explorer cannot roll forward. Loosen the rear lug nuts with the lug wrench, however, do not remove them yet.

    2

    Lift the rear of the Explorer with the jack and then lower it onto the jack stands, which you should place under the rear axle, out near the springs.

    3

    Remove the rear lug nuts and wheels from the Explorer. Set them off to the side, making sure to keep all the lug nuts together.

    4

    Put the catch pan on the ground below the left-rear brake rotor. Spray the brakes with the brake cleaner to remove the brake dust.

    5

    Remove the caliper mounting bolts with the socket set and then pull the caliper off the rotor. Slide the old pads out of the caliper and discard them.

    6

    Clean the inside of the caliper with brake cleaner and then lubricate the caliper slides with white lithium grease. Insert the new brake pads by hand and then slide the caliper back over the rotor. Bolt it back on with the socket set.

    7

    Repeat steps 4 through 6 on the right-rear brake assembly.

    8

    Put both rear wheels back on the Explorer and then install the lug nuts on both sides by hand. Lower the Explorer off the jack stands with the jack and then tighten the lug nuts to 100 ft-lbs with the torque wrench.

Rabu, 06 Mei 2009

Signs of Brake Failure

Few parts of your car are as important to the safety of you and your family as your brakes. Brakes are what allow you to stop for red lights, stop signs and the occasional deer. While total, instant brake failure is certainly possible, it is far more likely that your brakes will give you fair warning that something is the matter. Learning to recognize these signs can save you money at the shop and will help you keep your car safe.

Squeaks

    Brakes are designed with safety in mind. As the brake pad is worn down, it will eventually reach the "squeak" layer. This layer of the brake pad is engineered to make a high-pitched squeaking sound and alert the driver that it is time for a brake replacement. While you can certainly drive for a while on squeaky brakes, it is best to get them replaced as soon as possible to prevent damage to your vehicle.

Grinding

    If you run your brakes into the ground, you will likely experience a grinding feeling when the brakes are applied. This is the raw metal of the brake pad colliding with your brake disc. In addition to making harder to slow down, this will cause massive damage to the discs and rotors. The cost for replacing your brake pads is relatively low compared to the cost of new discs and rotors.

Pedal Issues

    If you hit your brakes and the pedal sinks all the way to the floor, you should get your brakes checked immediately. The same goes for brakes that need to be "primed" or pumped in order to operate. These are signs of a failure in the brake line or other vital component and could lead to an accident if not treated as soon as possible.

Pulsing and Pulling

    If you hit the brakes and it feels like your brakes are pulsing across a bumpy surface, it is entirely possible that your discs or rotors are warped. This is a clear indicator that something is going wrong. Additionally, if your vehicle pulls hard to one side or another when you press the brake pedal, you are likely experiencing some sort of brake failure on one side of the car. Have the brakes checked by a mechanic immediately.

Why Do You Rotate Brake Pistons?

Why Do You Rotate Brake Pistons?

A piston is a cylindrical device that transmits hydraulic or pneumatic force within a process. A brake piston, therefore, transmits force provided by hydraulically- or pneumatically-driven brakes. When a brake lever is pushed, the gas drives the piston to rotate, which allows the vehicle to brake.

Significance

    The rotation of a brake piston equates to force being exerted on a vehicle's braking system. Many vehicles have either hydraulic or pneumatic brake systems, which means they are driven by gas or air, respectively. When a brake lever is pressed or squeezed, it exerts force on the piston to rotate.

Function

    The rotation of the piston allows brake fluid to be released into the pressure chamber, and, ultimately, through the entire hydraulic system of the vehicle. When the brake pistons rotate, it applies force to the brake pads, causing them to be pushed against the rotation of the piston. The friction between the pads and the rotor generates a braking torque, which slows the vehicle.

Repair

    Another action referred to as brake piston rotation sometimes occurs during the installation of new brake pads. Many mechanics and auto repair shops have brake piston rotation tools. These are specialized tools designed to manually rotate the park brake piston into the brake caliper when replacing brake pads on vehicles.

What Is the Cause of Uneven Wear in Brake Pads?

What Is the Cause of Uneven Wear in Brake Pads?

As auto-repair shop prices continue to rise, you may be looking for any way to save money you can. One way to save money is to complete your car maintenance or repairs yourself, including brake pad replacements. While performing a brake job, you may notice that one pad wore down faster than the other did. A small amount of uneven brake pad wear is to be expected, but when there is significant uneven wear, you need to find the source and repair or replace it, or you are simply throwing away your hard-earned money.

Slide Pins

    On nearly all modern brake systems, the brake caliper rides on two pins that allow the caliper to slide back and forth as needed. To maximize the pins effectiveness, the pins must be smooth and well lubricated with disc brake grease. If these pins become dirty, rusty or lack lubrication, the caliper may stick in one spot on the pins. If the caliper sticks with one brake pad or another contacting the rotor, that brake pad will wear out faster than the other, resulting in uneven brake pad wear. To prevent this, always clean the caliper slide pins and apply new grease to them when performing a brake job.

Failed Caliper

    Inside all calipers is a piston that presses the brake pads against the rotor. This piston does not have a retracting feature, a square-cut O-ring retracts the piston just enough to release the brake pads. If this O-ring loses its elasticity, it will not retract the caliper piston, which results in the inner brake pad wearing out faster than the outer. Another cause of uneven wear by failed caliper is if the caliper piston or its cylinder becomes contaminated. This also prevents the piston from retracting and causes the inner brake pad to wear quicker than the outer pad. The best preventative measure for both failures seal and piston is to perform regular brake fluid changes. Once a year is how often most professionals recommended flushing the brake system, even if the manufacturer does not include brake fluid flushes in your vehicles maintenance schedule.

Rotor Defects

    The brake rotor is supposed to be a level surface, so the pad can grip it firmly with its entire friction surface. Over time, the rotor can develop small grooves in it. When this happens, you must resurface or replace it. Unfortunately, many do-it-yourself mechanics tend to overlook rotors when performing brake jobs and just put on new pads. Due to the rotors surface being harder than the friction material on the brake pad, any defects in the rotor transfer to the pads friction material, including grooves. You can prevent this type of uneven pad wear by thoroughly inspecting your vehicles rotors during each brake job and replacing or resurfacing them, as needed. Not only does this keep pad wear even, but it also improves your vehicles stopping distance.

Defective Brake Pads

    Like any mass-produced automotive component, there is the potential for poor workmanship. Brake pads undergo a series of inspections prior to hitting the parts store shelves, but human and computer errors do occur. If one brake pads friction material is less dense than the other even the slightest amount you will notice that one pad wears out quicker than the other. There is no way to prevent this, however, most brake pads come with a warranty and you can exchange the defective pads for new ones.