34 11 552 Overhauling left or right front brake caliper (TRW) (brake caliper removed)

Carefully force piston out through connection bore with compressed air.

To protect piston, place a protective plate (e.g. hard wood or hard felt) in caliper recess.

Do not grip piston with fingers - risk of trapping!

Fig 1: Caliper Recess Protective Plate

Courtesy of BMW OF NORTH AMERICA, INC.

Press off dust sleeve (1).

Fig 2: Dust Sleeve

Courtesy of BMW OF NORTH AMERICA, INC.

Carefully remove seal (1) with special tool Sealing lip wedge 00 9 316 in set 00 9 310 ASSEMBLY WEDGES (SET IN PLASTIC CASE) .

Clean cylinder bores and parts with alcohol and dry with compressed air.

Thoroughly inspect cylinder bore, piston and flange surfaces.

Machining of cylinders and pistons is not permitted.

Install new seal.

Installation: 

Apply a light coat of Ate brake cylinder paste to cylinder bore, piston and seal, refer to BMW Service Operating Fluids .

Fig 3: Seal And Special Tool (00 9 316)

Courtesy of BMW OF NORTH AMERICA, INC.

Fit dust sleeve (1) in groove (2) of brake caliper housing and press into the annular groove.

Installation: 

The area between the dust sleeve and the brake caliper housing must be kept dry. It must not come into contact with Ate brake cylinder paste or brake fluid so as to ensure that the dust sleeve is perfectly seated.

Fig 4: Dust Sleeve And Brake Caliper Housing Groove

Courtesy of BMW OF NORTH AMERICA, INC.

Lightly press brake piston against dust sleeve (1).

Inflate dust sleeve with compressed air (max. 2 bar) via the connection hole. Dust sleeve snaps over brake piston.

Installation: 

Coat dust sleeve and brake piston with brake fluid to facilitate installation of dust sleeve.

Press piston into cylinder bore until dust sleeve (1) snaps into annular groove (2) of brake piston.

Fig 5: Dust Sleeve And Brake Piston Annular Groove

Courtesy of BMW OF NORTH AMERICA, INC.