The Buick LeSabre uses disc brakes on both the front and rear wheels. However, changing the rear brakes is a bit different than changing the front ones because of a few extra components. You must change at least the brakes on both rear wheels together. They need to be changed every 60,000 miles, but may need to be changed more often depending on your driving habits.
Siphon out two-thirds of the brake fluid from the master cylinder with a siphoning kit or turkey baster that has never been used. Raise the rear end of the car on jack stands and remove the wheels; loosening the lug nuts with the lug wrench before raising the car makes the wheels easier to remove. Place two lug nuts on the on the rotor studs to keep the disc in place.2
Remove the bolt and washer that connects the cable support bracket to the caliper. You don't need to detach the cable, removing the bolt gives the cable enough slack to allow the caliper to move.3
Use a wrench to remove the lower caliper bolt and pivot the caliper upward. Hold the caliper in this position with mechanic's wire and make sure there is no strain on the brake hose. Remove the old pads and their anti-rattle clips from the caliper's mounting bracket.4
Turn the caliper's piston back into its bore with a two-pin spanner or pair of needle-nose pliers. The "slots" in the piston's face need to be perpendicular to a figurative line drawn through the caliper's mounting bolt holes. Make sure the piston boot lays flat; lift one edge of the boot with a small screwdriver to release trapped air.5
Apply anti-squeal compound to the new pads' backing plates. Install the old anti-rattle clips onto the caliper mounting bracket, make sure they are fully seated, then install the new pads.6
Lower the caliper back down onto the mounting bracket. Lubricate the lower mounting bolt with high-temperature grease before installing it back in place.7
Re-install the bolt to the cable support bracket--use a new washer--and make sure the cable is tight. Reattach the wheels and lower the car after changing the brakes on both sides. Check the brake fluid level in the master cylinder and add fluid as needed. Pump the brake pedal several times to seat the brakes.