GM 10434245
Rotor

Begin replacing the front Brake Disc by checking the brake master cylinder reservoir fluid. Decrease the fluid to the midpoint mark if it sits above but below the maximum and minimum marks. Lift the vehicle up and take off both tire and wheel to start the work. Apply the c-clamp against the back of the outboard Brake Pad and pull the brake caliper into the bore until you can take it off the Brake Disc. Place the brake caliper on heavy mechanic's wire to protect the hydraulic flexible brake hose during the process. Take off bolted brake caliper pieces with the brake caliper in place without disconnecting the hydraulic brake hose. Support the brake caliper assembly with wire and strap before removing the Brake Disc. Before adding the new Brake Disc you must scrub away rust from its mounting surface and treat the hub flange with the hub cleaning kit j 42450-a. Secure the Brake Caliper Bracket directly onto the brake caliper and verify the threads for both parts and mounting holes in the knuckle remain free of debris and damaged. Add threadlocker gm p/n 12345493 (Canada P/N 10953488) to the bolts threads of the Brake Caliper Bracket before tightening them to 185 nm (137 ft. Lbs.). Wrap up work by placing the wheel and tire on, lowering the vehicle plus filling the master cylinder until it reaches its required level. Additionally, if you installed a fresh Brake Disc or had it refinished you must burnish the pads and disc.

Install the brake rotor, caliper bracket, tire, and wheel, and then lower the vehicle.

Support the brake caliper with heavy mechanic's wire to prevent damage to the hydraulic flexible brake hose.

It is crucial to prevent lateral runout and brake pulsation.

Install and tighten the caliper bracket bolts to 130 Nm (96 ft. lbs.).

Use a C-clamp (J 41a13) to compress the brake caliper piston enough to slide the caliper away from the rotor, and then remove the C-clamp.

Refinish the rotor according to the lathe manufacturer's instructions, inspecting the thickness after each cut.