Before working on the rear Brake Disc of a 2500 series vehicle you must release the parking brake first then check the brake fluid level in the reservoir and drain excess fluid if needed up to the middle span between highest and lowest marks. Lift the car up and secure it in place before taking out the tire wheel assembly to set the disc position against the hub. Press the brake caliper pistons in with a large j 41013 c-clamp applied over the caliper unit until all pistons are compressed fully. Secure the brake caliper through heavy mechanical wire to safeguard the hydraulic flexible brake hose. Use appropriate tools to take out
Brake Caliper Bracket bolts first then disconnect the bracket-caliper unit as one system without disconnecting the hydraulic hose. You should take off the Brake Disc retaining push nuts first. Afterwards, use a deadblow hammer to hit and separate the hub or disc when this step is required. Use the wheel hub resurfacing kit and disc resurfacing kit to eliminate all rust and contamination from both hub flange and Brake Disc surfaces. Put the disc back in its proper alignment before installing it by rotating and pressing it towards the axle. Check and adjust the assembled lateral runout measurement for brake system applications if results exceed defined specs. Put back the caliper and bracket system and take off the old adhesive from bolt threads then wipe with brake parts cleaner before applying threads gm p/n 12345493 (Canada 10953488) and bolt down to 148 lb ft torque. Reattach the tire while lowering the vehicle and exercise the brake pedal gently while avoiding the engine. Top up the master cylinder only when needed with brake fluid.