Removing and Installing/Replacing Brake Pads on Both Rear Disc Brakes

34 21 200 - Removing and installing or replacing brake pads on both rear disc brakes





Special tools required:
- 34 1 050
- 34 1 080
- 34 1 280





Important!
The brake pad wear sensor must be replaced once it has been removed (brake pad wear sensor loses its retention capability in the brake pad).

So as not to damage the surface coating, if possible do not mechanically clean the guide surfaces for the brake pads on the brake caliper holder. Instead, clean with brake cleaner BMW part no. 83 19 2 147 681 and apply a thin coating of Never-Seez(R) Compound brake pad paste BMW part no. 83 23 9 407 830.





Necessary preliminary tasks:
- Remove wheels
- Remove brake pad wear sensor Removal and Replacement

Observe safety instructions on raising the vehicle.





Remove plastic plugs (1).

Right side:

Disconnect plug connection for brake pad wear sensor.





Release guide screws (2) with special tool 34 1 080 .

Installation:
Only clean guide screws; do not grease.

Check threads.

Replace all guide screws which are not in perfect condition.

Tightening torque 34 21 5AZ .





Lift out retaining spring (3).

Withdraw brake caliper backwards.





Turn piston fully back with special tool 34 1 050 .

Important!
When forcing piston back:

- Pay attention to brake fluid level in expansion tank; brake fluid that spills over will damage paintwork.





Remove outer brake pad.

Inner brake pad is located with its spring in the piston.

Important!
Mark any worn brake pads.

If the brake pads are worn on one side, they must not be mixed up!

Observe minimum thickness of brake pads .

Clean brake pads.

Do not apply grease to brake pad backplate.





Check minimum brake disc thickness:

- Position special tool 34 1 280 at three measuring points in area (1) and measure.
- Compare measurement result and lowest value with setpoint value .





Important!
New brake pads may only be installed if the brake disc thickness is greater than or equal to the minimum brake disc thickness (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 (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).





Check dust sleeve (1) for damage and replace if necessary.

Clean contact surface (2) of brake piston with brake cleaner and apply a thin coating of brake pad paste.

Important!
Dust sleeve must not come into contact with anti-squeak compound as this may cause the dust sleeve to swell.





Clean contact surfaces (1) and (2) of brake pad tee heads/brake caliper housing with brake cleaner and apply a thin coating of brake pad paste.





Clean contact surface (3) of brake caliper with brake cleaner and apply a thin coating of brake pad paste.





So as not to damage the surface coating, if possible do not mechanically clean the guide surfaces for the brake pads on the brake caliper holder. Instead, clean with brake cleaner and apply a thin coating of Never-Seez(R) Compound brake pad paste.





Note:
After completing work:

- Fully depress brake pedal several times so that brake pads contact brake discs.
- When installing new brake pads at front and rear axles, brake fluid level must be brought up to "MAX" marking.
- Read and comply with notes on braking in new brake discs / brake pads Procedures.
- If necessary, when replacing pads, reset CBS display in accordance with factory specification.

Important!
On the E60 M5 and E63 M6 the fault memory entry "Mastervac vacuum pressure sensor" may be stored after the brake pads have been replaced.

The fault memory entry must be deleted. The vacuum pressure sensor only has to be replaced if the fault is entered repeatedly.

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