GM 89060218
Caliper

Service and repair work on the rear brake caliper needs these items: universal driver (J8092) and caliper boot seal installer (J 45507). First take out the brake caliper from the vehicle then put clean cloths inside the caliper storage for Piston removal. Air at low pressure helps the pistons exit their bores but the technician should not cause any harm. Extract the Piston dust boot seal and Piston seal using a wooden or plastic tool and detach the brake caliper bleeder valve cap followed by the valve itself. Check the Brake Caliper Bracket for damage and rust symptoms then switch it if needed. Clean the Brake Caliper Piston bore and seal counter-bore with denatured alcohol then blow dry them with non-oiled filtered air. Replace the brake caliper unit when you find any breaks, scuffs, pits or heavy rust on its Piston and bore area. Load the brake caliper bleeder valve and fasten it to 14 n.m (124 lb in) torque before putting on the bleeder valve cap. Put delco supreme 11 brake fluid (part:12377967) into the new Piston seal and push it into the caliper bore seal groove without twisting it. Before setting the Piston in place apply brake fluid inside both the bore and Piston. Put the dust boot seal inside the caliper with the universal driver tool when using the caliper boot seal installer tool to make sure the seal fits perfectly into its groove. Reapply the calibrated component onto its regular position.

Remove the brake caliper pin bolts and take off the caliper from the bracket.

Use Delco Supreme 11®, GM P/N 12377967 (Canadian P/N 992667) or equivalent DOT-3 brake fluid.

Install them over the pistons.

Gradually apply the brake pedal to approximately 2/3 of its travel distance with the engine OFF, slowly release it, and repeat until a firm pedal is obtained.

A thin coat of high temperature silicone lube.

Inspect for any cracks, scoring, or excessive corrosion, replacing the caliper assembly if needed.

Install the caliper back onto the vehicle.

Remove the plug from the brake caliper opening and the brake hose, then install new copper brake hose gaskets and the brake hose fitting bolt, tightening it to 34 Nm (25 lb ft).

Apply low pressure compressed air.

Clean the threads and holes with denatured alcohol, then apply threadlocker GM P/N 12345493 (Canadian P/N 10953488) to 2/3 of the threaded length of the lower caliper bracket bolts and allow it to cure for about 10 minutes.

Remove the plugs from the brake caliper and hose, install new copper brake hose gaskets, and attach the brake hose and bolt, tightening to 50 N.m (37 lb ft).

Raise and support the vehicle, then remove the tire and wheel assembly.

Bleeding of the brake system may be necessary.