Even if you lack mechanical experience, a brake caliper repair on your car or truck can be achieved successfully if you have the right tools, a moderate degree of mechanical skills, and the right instructions. First, you should understand what automobile calipers are: Simply put, they are clamps in the wheel's braking system that apply friction to the brake disc which slows—or stops—the vehicle. Brake fluid in the braking system is prevented from leaking by means of a seal in the caliper. When this seal is damaged or worn, the fluid can leak, reducing the caliper's ability to maintain the pressure required to brake the car or truck. But these calipers can be repaired, using special kits. Here's what you'll need to repair your car's brake calipers, along with instructions for repairing them.
Step 1 – Remove the Wheels
Before raising your car, loosen each wheel's lug nuts a quarter turn, just enough to break the nuts loose. Use your automobile jack to raise your car. First, the front end, then the rear. When you have it raised, slip jack stands under the car, then lower the car enough to rest the car's weight safely on the jack stands. Then, remove all lug nuts from the wheels, remove the wheels from the car, and set them aside, along with the lug nuts.
Step 2 – Clean Brake Parts and Caliper
Use a clean rag and brake cleaner to clean brake parts. Locate caliper bolts behind the caliper, remove the bolts, disconnect the brake line at the caliper, and remove the caliper. Use the rag and brake cleaner to clean the caliper. Remove dust seals you'll find on the caliper's piston, then remove the piston. After removing the O-ring from the caliper, clean internal surfaces of the caliper.
Step 3 – Insert New Seals
Before inserting new seals, use new brake fluid to lubricate the new seal and caliper piston. This will make piston re-installation easier. Into the caliper groove insert the new seal and slide the piston back into the caliper, then install the dust seal by fitting it over the piston lip and installing the metal ring that clamps it to the piston.
Step 4 – Replace the Caliper
Compress the caliper piston and slide the caliper into position over the rotor. Replace the caliper bolts and tighten them. Next, reconnect the brake line and bleed the brakes, according to manufacturer's directions. Repeat this process at the other wheels where seals need replacing. Test your car's brakes by compressing your brake pedal. If the pedal is excessively soft examine the seals for leakage. If necessary, bleed the brake line again.
Step 5 – Finish
Reattach the car's wheels, remove the jack stands, lower the car, and tighten the lug nuts on all the car's wheels.