A8L V8-4.2L (BFM) (2004)
Brake Caliper: Overhaul
Front Brake Caliper Piston, Ceramic Brakes
Front Brake Caliper Piston, Ceramic Brakes
Special tools, testers and auxiliary items required
‹› Wedge (3409)
‹› Piston resetting tool (T10145)
Removing
-
Force piston from brake caliper housing, one at a time, using compressed air.
Only one piston can be pressed out at a time. Secure opposite piston in brake caliper housing using piston resetting tool - a -. Block the other pistons,
e.g. using wood blocks - b -. In addition, place a wooden board - c - in front of the piston resetting tool so that the piston will not be damaged when
pressed out.
-
Remove seal with (3409).
When removing, make sure that surface of cylinder is not damaged.
Installing
The brake pistons have different diameters. When reinstalling, ensure the respective brake piston is inserted in the correct bore in the
brake caliper. The ceramic inserts on the brake pistons serve as heat insulators and must not be removed from the pistons. If the ceramic
inserts are damaged, the brake pistons must be replaced for safety reasons.