Some vehicles may be equipped dual piston calipers. The procedure to overhaul the caliper is essentially the same with the exception of multiple pistons, O-rings and dust boots.
- Remove the caliper from the vehicle and place on a clean workbench.
Depending upon the vehicle, there are two different ways to remove the piston from the caliper. Refer to the brake pad replacement procedure to make sure you have the correct procedure for your vehicle.
The first method is as follows:
- Stuff a shop towel or a block of wood into the caliper to catch the piston.
Remove the caliper piston using compressed air applied into the caliper inlet hole. Inspect the piston for scoring, nicks, corrosion and/or worn or damaged chrome plating. The piston must be replaced if any of these conditions are found.
- For the second method, you must rotate the piston to retract it from the caliper.
- If equipped, remove the anti-rattle clip.
- Use a prytool to remove the caliper boot, being careful NOT to scratch the housing bore.
- Remove the piston seals from the groove in the caliper bore.
- Carefully loosen the brake bleeder valve cap and valve from the caliper housing.
- Inspect the caliper bores, pistons and mounting threads for scoring or excessive wear.
- Use crocus cloth to polish out light corrosion from the piston and bore.
- Clean all parts with denatured alcohol and dry with compressed air.
- Lubricate and install the bleeder valve and cap.
- Install the new seals into the caliper bore grooves, making sure they are NOT twisted.
- Lubricate the piston bore.
- Install the pistons and boots into the bores of the calipers and push to the bottom of the bores.
- Use a suitable driving tool to seat the boots in the housing.
- Install the caliper in the vehicle.
- Install the wheel and tire assembly, then carefully lower the vehicle.
- Properly bleed the brake system.
Removal & Installation
- Loosen the wheel lug nuts slightly.
- Raise and support the vehicle safely.
- Remove the wheels.
- Disconnect the brake hose from the caliper. Plug the end of the hose to prevent loss of fluid. Some brake lines have a union bolt and gasket type line attached to the caliper. Do NOT lose the washers.
Have a container handy to catch brake fluid from the disconnected lines.
- Hold the sliding pin and remove the bolts that attach the caliper to the torque plate.
- With two hands, lift up and remove the caliper assembly.
- Grease the caliper pins and bolts with Lithium grease or equivalent. Temporarily install the caliper on the torque plate with the installation bolts.
- Hold the sliding pin and tighten the installation bolts to 25 ft. lbs. (34 Nm) on the front wheels, and 14 ft. lbs. (20 Nm) in the rear.
- Attach the flexible brake hose to the caliper with new gaskets. Tighten the hose to 22 ft. lbs. (30 Nm).
Install the brake hose lock securely in the lock hole, in the caliper.
- Fill and bleed the system.
- Install the wheel, lower the vehicle and tighten the lug nuts.
- Before moving the vehicle, make sure to pump the brake pedal to seat the pads against the rotors.
- Check for leaks.
- Before servicing the vehicle, refer to the Precautions section.
- Remove the wheels.
- Disconnect the brake hose from the caliper.
- Remove the bolts that attach the caliper to the torque plate. If applicable, hold the flats of the sliding pin with a wrench while loosening the caliper attaching bolts.
- Lift up and remove the caliper assembly.
- Install the caliper and loosely install the bolts.
- Hold the flats of the sliding pin with a wrench, then tighten the bolts. Tighten to 25 ft. lbs. (34 Nm) except on Celica rear calipers. Tighten the bolts on Celica rear calipers to 34 ft. lbs. (47 Nm).
- Connect the brake hose to the caliper, using 2 new washers.
- Fill the brake system to the proper level and bleed the brake system.
- Add brake fluid to the reservoir to fill to the correct level.
Lower the vehicle to the ground.