A brake squeak or squeal may randomly begin when you are driving, even if you have recently had the brakes serviced. The squeak may be quiet at first, and it may come and go; however, if you hear this noise you should inspect your brakes to determine the cause. The most common reason for squeaking brakes is worn out or improperly lubricated brake pads. There are, however, other reasons for squeaking brakes that should be considered before replacing the brake pads.
Remove the wheel. Place the car jack underneath the vehicle, at a suitable jack-point, and use the jack to raise the vehicle. Place jack stands underneath the vehicle and lower the jack until the vehicle is resting on the jack stands. Place wheel chocks underneath the wheels that are touching the ground. Use the torque wrench and the socket set to remove the lug nuts from the wheel, and remove the wheel.2
Determine the cause of the noise. Inspect the brake pads or brake shoes to see if they are worn down. Check the brake pads to see if there is enough lubricant applied to the back of them. Make sure that the pads fit tightly within the calipers. If there does not appear to be a problem with the brake pads or shoes, inspect the other components of the brakes. Check the calipers, as well as the caliper slides, pins and bushings; you may have to replace these parts if there is too much looseness between the caliper and the knuckle. Check the brake rotors. The rotors may need resurfacing if they have become glazed or rough, or if they were not finished properly. If your vehicle has drum-style brakes, check for excessive brake dust, as well as loose hardware.3
Replace any worn parts and apply lubricant. If the cause of the problem is determined to be a worn out part, replace the part. The most common problem is worn out or improperly lubricated pads or shoes. Apply lubricant to the backs of the brake pads, or to the brake shoe contact areas. For drum-style brakes, if there is too much brake dust, remove the brake drum and clean the components with brake cleaner.4
Install the wheel and lower the vehicle. Put the wheel back in place, and use the torque wrench and the socket set to tighten the wheel lug nuts to the correct torque specification; refer to the vehicle repair guide to determine the correct specification. Raise the vehicle to bring it off of the jack stands, and remove the jack stands. Remove the wheel chocks. Lower the vehicle and remove the car jack. Pump the brake pedal and test the brakes to ensure they are working correctly, before driving on a public road.