Replacing Rear Disc Brake Pads

In addition to the pads themselves, four self-locking bolts are required, which are normally included with the pads. Although the job is straightforward, you may encounter problems if the Audi special tool 3131 is not available.

The following description can therefore only help if you can borrow this tool from a workshop or make one based on the original.

The illustration shows the Audi special tool 3131 being used to push back the brake piston of the rear disc brake with the caliper removed.

PROCEDURE

Remove both caliper housing mounting bolts, holding the guide bolt by its hex head.

Pull the caliper housing outward by hand.

Now tilt it backward and remove it.

Remove the brake pads from the guides.

Fit special tool 3131 to the brake piston and turn the piston in by applying firm hand pressure.

Have an assistant monitor the brake fluid level in the reservoir during this step. If the reservoir overflows, remove fluid.

Never force the brake piston back without turning it. Doing so will damage the adjusting mechanism in the piston.

Install new brake pads.

Tighten the caliper housing with new self-locking bolts to 35 N·m.

To hold the guide bolt, use only a thin open-end wrench. A wide wrench may jam, and the tightening torque will then be inaccurate.

After disassembling the brake assembly, the basic adjustment must be performed (see next section).