Audi Workshop Service and Repair Manuals

Removing and installing pistons for front brake caliper Special tools and workshop equipment required

t  Wedge -3409-

t  Piston resetting appliance -T10145- t  Lithium grease -G 052 150 A2- Removing

–  Force pistons out of brake caliper housing one at a time using compressed air. The pistons can only be removed one at a time. Hold the opposite piston in the caliper housing with piston resetting appliance -a-. Use blocks of wood or similar -b- to keep the other pistons in place. Also place a piece of wood -c- against the resetting tool to prevent the piston from being damaged when it is forced out.

–  Remove seal using removal wedge -3409-. When removing ensure that the bore of the cylinder is not damaged. Installing –  The surface of the piston and seal should be cleaned using only methylated spirits and then dried. –  Apply a thin coat of lithium grease -G 052 150 A2- to piston and seal before inserting.

–  Insert the seal into the brake caliper housing.

–  Fit protective cap onto piston.

–  Push piston into caliper housing, exerting even pressure. The protective cap must fit securely in the groove; if necessary, apply additional pressure with piston resetting appliance.