Rear brake caliper piston, removing and installing

WARNING: This page does not describe the selected car, but rather 17 other vehicles, including the 2009 Audi S4, 2009 Audi A4, 2008 Audi S4, 2008 Audi RS 4, and 2008 Audi A4. However, it is still accessible from the selected car via links, so may be relevant.

Special tools, testers and auxiliary items required

Fig 1: Resetting Extracting Tool T10165

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Resetting extracting tool T10165
or Reset and screw out tool 3272

Fig 2: Plate 3272/1

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Plate 3272/1

Fig 3: Identifying Trim Removal Wedge 3409

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Trim removal wedge 3409
Bleeder bottle

Removing

Fig 4: Extracting Piston From Brake Caliper Housing By Turning Knurled Wheel Counter-Clockwise

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Extract piston from brake caliper housing by turning knurled wheel counter-clockwise.

NOTE:

Install reset and screw out tool 3272 so that the collar is positioned against the piston.
If piston is difficult to move, use a 13 mm open end wrench on the flats - arrow A -.

Fig 5: Removing Seal Using Wedge 3409

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Use trim removal wedge 3409 to remove seal.

NOTE:

When removing make sure that the hole 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 O-ring into brake caliper housing.

Fig 6: Placing Protective Seal With Outer Sealing Lip On The Piston

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Place protective cap with the outer sealing lip on the piston.

Fig 7: Inserting Inner Sealing Lip Into The Grove In The Cylinder Using Wedge 3409

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Using trim removal wedge 3409 , insert inner sealing lip into cylinder groove.

NOTE:

When doing this, hold piston in front of caliper housing.

Fig 8: Extracting Piston From Brake Caliper Housing By Turning Knurled Wheel Counter-Clockwise

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Screw piston in by turning knurled wheel clockwise.

NOTE:

Install reset and screw out tool 3272 so that the collar of the tool is positioned against plate 3272/1.
If piston is difficult to move, use a 13 mm open end wrench on the flats - arrow A -.

Install brake pads.

Pre-bleeding brake caliper

Fig 9: Identifying Bleed Valve, Standard Bleeder Bottle & Threaded Hole

Courtesy of VOLKSWAGEN UNITED STATES, INC.

Open bleeder valve - arrow A - and, using a standard bleeder bottle, fill with brake fluid until bubble-free brake fluid flows from the threaded hole - arrow B - (brake hose connection). Close bleeder valve.

NOTE:

Position brake caliper as illustrated for pre-bleeding.