How to Retract an Audi Caliper


1. Clean the caliper and nearby areas with brake cleaner. If you are having to retract the caliper piston, that probably means you are installing new brake pads.
2. Remove the lid on the brake fluid reservoir and inspect the brake fluid level. If the level of the fluid is relatively low, proceed with retracting the caliper. However, if the fluid is right at the top, the pressure from pushing the piston into the caliper may cause the fluid to overflow. Remove some of the brake fluid with a turkey baster or large syringe if you do want the fluid to spill out. You can also simply put rags around the reservoir.
3. Support the brake caliper with something while you are retracting the piston so that it does not hang on the brake line and potentially damage it.
4. Slide a caliper piston retracting tool onto the slots in the caliper and turn the piston with the tool while pressing it into the caliper. You may need to use a C-clamp to tighten the piston into the caliper while simultaneously turning it. Retract the caliper until there is enough clearance between the pads and the rotor to slide the caliper over the rotor. You will have to stop and check this by temporarily installing the pads, since you cannot retract the piston with the pads installed.
5. Slide the caliper over the rotor once you have retracted the pistons enough. Tighten the caliper bolts. Top off the brake fluid and put the lid back on the reservoir.