Removing and Installing/Replacing Both Rear Brake Discs

34 21 320 - Removing and installing or replacing both rear brake discs





Special tools required:
- 34 1 280 34 1 280 Sliding Caliper





Necessary preliminary tasks:
- Remove wheels Removing or Installing Front or Rear Wheel
- If necessary, remove and clean brake pads Removing and Installing/Replacing Brake Pads on Both Rear Disc Brakes
E65 and E66: Release parking brake (pushbutton to left of steering wheel).

After completing work:

- Adjust handbrake Adjustments (not for E65 and E66)
- Read and comply with notes on braking in new brake discs / brake pads Procedures.
Observe safety instructions on raising the vehicle 00 .. ... Lifting Vehicle With A Lifting Platform.





Check minimum brake disc thickness:

- Position special tool 34 1 280 34 1 280 Sliding Caliper at three measuring points in area (1) and measure.
- Compare measurement result and lowest value with setpoint value [1][2]34 21 Rear Brake.
Always replace brake discs in pairs.

If the brake discs are replaced, you must also fit new brake pads.





Important!
New brake pads may only be installed if the brake disc thickness is greater than or equal to the minimum brake disc thickness [1][2]34 21 Rear Brake (MIN TH) (not incl. M vehicles).

In the case of M vehicles and perforated brake discs, new brake pads may only be installed if the brake disc thickness is greater than the minimum brake disc thickness [1][2]34 21 Rear Brake (MIN TH).

Note:
The minimum brake disc thickness is configured in such a way that it lasts the life of a further set of brake pads (does not apply to M vehicles and perforated brake discs).





Release screws (1), remove brake caliper and tie up.

Note:
Brake hose remains connected.

Installation:
Tightening torque 34 21 3AZ 34 21 Rear Brake.





Unscrew bolts and take off brake disc.

Installation:
Tightening torque 34 21 1AZ 34 21 Rear Brake.

Clean contact surface of brake disc at wheel hub thoroughly and remove traces of corrosion if necessary. Unevenness on contact surface may result in distortion of brake disc!

Important!
To release brake disc: Do not under any circumstances strike friction ring with a hammer or similar! If necessary, carefully tap on base of brake disc chamber with a rubber mallet.





Important!
Internally ventilated brake discs are balanced.

Never remove or reposition balance clips.

NOTE:
- If brakes pads have been replaced during procedure, reset CBS display in accordance with factory specification, please refer to: Vehicle/ Instrument Panel/ Gauges and Warning Indicators/ Maintenance Required Lamp Indicator/ Service and Repair Service and Repair