BMW 34216855004 Ventilated Brake Disc

Firmly block the front wheels, then raise the rear of the vehicle and support it securely on jackstands. Remove the appropriate rear wheel. Release the parking brake. Inspect the disc. Removal: Remove the brake pads. Remove the bolts and remove the caliper mounting bracket. Discard the bolts; new ones must be installed. Loosen and remove the brake disc retaining bolt. It should now be possible to remove the brake disc from the stub axle by hand. If it is tight, lightly tap its rear face with a plastic mallet. If the parking brake shoes are binding, check that the parking brake is fully released. Fully release the parking brake cable tension to obtain maximum freeplay in the cable. Insert a screwdriver through one of the wheel bolt holes in the brake disc, and rotate the adjuster star wheel on the upper pivot to retract the shoes. The brake disc can then be removed. Installation: Ensure that the mating surfaces of the disc and hub are clean and flat. Align the marks made on removal, and tighten the disc retaining bolt to the specified torque. If a new disc has been installed, use solvent to wipe any anti-corrosion preservative coating from the disc before installing the caliper. Ensure the disc mounting surface on the hub is free from dirt and corrosion. Slide the caliper into position over the disc, making sure the pads slide pass either side of the disc. Tighten the caliper mounting bolts to the specified torque. Install the wheel, then lower the vehicle to the ground and tighten the wheel bolts to the specified torque. Adjust the parking-brake shoes and cable. Depress the brake pedal a few times to bring the brake pads into contact with the disc. Bleeding won't be necessary unless the brake hose is disconnected from the caliper. Check the operation of the brakes carefully before driving the vehicle. Recheck the parking brake.

Measure the brake disc diameter on the vehicle and check it against the corresponding brake disc specifications for the front or rear brakes. Additional application information is available through parts data and the authorized BMW dealer parts department. Machine or replace brake discs in pairs per axle. Begin by raising the car and supporting it safely, then remove the wheels. Next, remove the brake caliper carrier bolts and suspend the brake caliper from the chassis using stiff wire, ensuring the hydraulic brake line remains connected. Remove the brake disc mounting screw and take off the disc, inspecting it for cracks, signs of overheating, and scoring. The minimum allowable thickness is stamped on the disc hub. Measure the disc braking surface with a micrometer at eight to ten different points, using the smallest measurement for comparison against the specifications. If the disc does not meet minimum thickness requirements or is damaged, it should be replaced. Clean the disc with brake cleaner before installation, and when installing new rear brake discs, adjust the parking brake accordingly.