GM 15712803
Rotor

You need j 41013 disc resurfacing kit and j 42450-a wheel hub resurfacing kit to replace the front Brake Disc on a 25/3500 series vehicle. Prepare the new disc surface friction areas by applying denatured alcohol before detaching the wheel and tire setup. You can remove the front hub extension on dual wheel vehicles by labeling its placement on the hub before unlocking and tapping its perimeter with a rubber mallet if needed. Begin your work only after making sure the brake master cylinder reservoir holds fluids at its midpoint between highest and lowest marks. Place the disc marks on the hub to align the parts correctly. Apply both c-clamps to compress the brake caliper pistons. Detach the caliper unit with its bracket from the vehicle while keeping the hydraulic hose attached. Remove Brake Disc securing nuts when needed then hit the disc gently with a deadblow hammer to unhitch it from the hub. To eliminate corrosion apply penetrating oil and force the disc off using two m10 x 1.5 bolts. Wash away all rust and debris from both hub/axle flange and Brake Disc connection points using products j 42450-a and j 41013. Refuse installing the disc if you see marks or nicks on the hub flange. Put the disc on stands to measure its assembled lateral runout then make necessary changes before putting back the caliper and bracket. Clean all bolts on the caliper bracket threads before adding threadlocker gm part number 12345493 (Canadian part number 10953488). Tighten all bolts to 300 nm (221 ft. Lbs.). Reposition the front wheel hub extension of two-wheeled vehicles while keeping it straight then securing the nuts at 130 nm (96 ft. Lbs.). Reattach the tire and wheel parts before pressing the brake pedal slowly to settle the pads and pistons into position. Meanwhile top up the master cylinder reservoir with fresh brake fluid as required.

Before beginning work on the rear brake disc JH7 you should release the parking brake then lift and secure the vehicle. Pull out the tire and wheel unit first before detaching the hub and disc part. Note how the hub fits with the disc for accurate reinstallation. Set the hub and disc parts onto a hydraulic press tool to push wheel studs through their mounts. Pull apart the hub and disc before fitting them together correctly to put back in place. Insert one wheel stud into the hub and disc assembly through its opening then add four washers and tighten the lug nut with the flat face touching the washers. Tighten the lug nut until the stud goes fully into the assembly then remove everything. Put back the hub and disc unit on the car then put on the tire and wheel set. Lower the vehicle afterwards. Brake cleaner or denatured alcohol needs to expose new discs by removing their protective coating before usage because oil-based materials harm brake pads and create fire risks.

To change the rear rotor on the 25/3500 series vehicle with dual wheels, first release the brake park or remove the hub and rotor assembly and mark the relationship between the hub and rotor. Bolt the hub and rotor to a hydraulic press and drive the wheel studs outward using the press. Align the hub and rotor and then install each new wheel stud with inserting, 4 washers, and attach a lug nut with the flat side facing the washers. Screw the lug nut as tight as possible to pull the stud into the hub and rotor so that the hub is against the rotor and the stud is fully engaged then removing the lug nut and washers. Reinstall the hub and rotor assembly to the vehicle when the engine is off, slowly push down on the brake pedal to approximately 2/3 of its travel and then release it in a slow manner. After 15 seconds, do this step all over again until a firm pedal can be attained, which will allow the brake caliper pistons and brake pads to sit in position properly. Lastly, top up the master cylinder reservoir with clean brake fluid to the right level if needed.

Mark the rotor's relationship to the hub, and use a C-clamp (J41013) to compress the brake caliper pistons for caliper removal.

Reinstall the tire and wheel assembly.

Burnish the brake pads and rotors.

Lower the vehicle and properly seat the brake caliper pistons and pads by applying and releasing the brake pedal several times before filling the master cylinder reservoir with clean brake fluid.

Tap the perimeter of the hub extension with a rubber mallet to loosen it.

Reinstall the tire and wheel assembly, lower the vehicle, and properly seat the brake caliper pistons and pads by applying and releasing the brake pedal several times before filling the master cylinder reservoir with clean brake fluid.

Reinstall the front wheel hub extension if equipped, ensuring it is aligned and tightened to 130 Nm (96 lb ft).

Begin by releasing the park brake and raising the vehicle securely.

Measure the assembled lateral runout (LRO) of the brake rotor; if it exceeds specifications, correct it.

Remove the park brake actuator lever housing from the backing plate, followed by the backing plate itself.

Rotor Resurfacing Kit (J 41013) and Wheel Hub Resurfacing Kit (J 42450-A).

Reinstall the tire and wheel assembly, and lower the vehicle.

Apply a non-directional finish using either a non-directional finishing tool with 120 grit aluminum oxide sandpaper or a sanding block with 150 grit aluminum oxide sandpaper, followed by cleaning each friction surface with denatured alcohol or an approved brake cleaner.

Clean the surfaces, apply penetrating oil, and use two M10 x 1.5 bolts to force the rotor off.

Use a drift or large screwdriver.

Continue to hold the rotor in place while installing the remaining Conical Brake Rotor Washers (J 45101-100) and lug nuts onto the wheel studs, tightening them firmly by hand in a star-pattern.

The rotor's relationship to the hub.

Refinishing is necessary if there is significant thickness variation, excessive corrosion, cracks, blueing discoloration, or scoring beyond specifications.

It must be replaced.

Place the hub and rotor assembly on a hydraulic press and press the wheel studs out.

Fill the master cylinder reservoir to the proper level with clean brake fluid.

Ensure no debris remains on the mating surfaces.

Reinstall the tire and wheel assembly, and lower the vehicle.

Brake rotor thickness variation should be measured.

Clean the threads of the bolts with brake parts cleaner and apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488).

Ensure the hub flange is free of nicks or marks.