34 21 200 Removing and Installing or Replacing Brake Pads on Both Rear Disc Brakes (TRW Floating Caliper)

34 21 200 Removing and installing or replacing brake pads on both rear disc brakes (TRW floating caliper)

Special tools required:







IMPORTANT:
- Brake pad wear sensor: after removal it must be replaced (brake pad wear sensor loses its retention capability in the break pad).
- Retaining spring: for vehicles older than 48 months it is recommended to replace the retaining spring.

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 mounting bracket. Instead, clean with brake cleaner BMW part no. 83 19 2 154 780 and apply a thin coating of brake pad paste BMW part no. 83 19 2 158 851.







Necessary preliminary tasks:
- Remove wheels.
- Remove rear brake pad wear sensor







Release guide screw (1).
If necessary, grip at hexagon head.
Tilt brake caliper upwards.

Installation note:
Replace guide bolts.
Tightening torque 34 21 5AZ.







Remove brake pads (1) in direction of arrow from brake anchor plate.

IMPORTANT:
Mark any worn brake pads.
In the event of one-sided brake pad wear, do not change brake pads round.

Observe minimum thickness of brake pads.
Clean brake pads.
Do not apply grease to brake lining 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 set point value.







IMPORTANT: New brake pads may only be fitted if the brake disc thickness is greater than the minimum brake disc thickness (MIN TH).







Press brake piston fully back with special tool 34 1 050.

IMPORTANT:
When pressing piston back, note brake fluid level in expansion tank.
Overflowing brake fluid will damage the paintwork.







Check dust boot (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 boot must not come into contact with brake pad paste as this may cause the dust boot to swell.







Clean contact surface (1) of brake caliper with brake cleaner and apply a thin coating of brake pad paste.







Clean hammerhead guide with brake cleaner and apply a thin coating of brake pad paste.

IMPORTANT: Brake pad with bulge (1) is intended for accommodating the brake pad wear sensor and must be fitted on the piston side.







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.
- When replacing pads, reset CBS display in accordance with factory specification.







Replacement:
Remove pad retaining springs (1).

Installation note:
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 mounting bracket. Instead, clean with brake cleaner and apply a thin coating of brake pad paste.