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

WARNING: This page is about a different variant/trim than selected.

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.

IMPORTANT: European version only.
Sport brake pads for M3:

Due to the increased strain on the brake discs, we recommend that you also replace the BRAKE DISCS when fitting a new set of brake pads
It is absolutely essential to replace the BRAKE DISCS if cracked ≥ 13 mm even before the brake pad is worn

Necessary preliminary work

Remove WHEELS .
Remove BRAKE PAD WEAR SENSOR

Lift out retaining spring (1).

Fig 1: Lifting Retaining Spring

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Remove cover plug (1).

Fig 2: Identifying Brake Pad Sensor Cover Plug

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IMPORTANT: Tie brake caliper back and do not allow to hang from brake hose.

Unscrew guide bolts (1).

Remove brake caliper (2) by pulling forward.

Installation note:

Tightening torque 34 21 4AZ .

Fig 3: Identifying Brake Caliper And Guide Bolts

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Clean guide screws only; do not grease.

Check threads.

Replace all guide bolts which are not in perfect condition.

Remove outer brake pad.

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

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

Fig 4: Removing Brake Pad

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Clean brake pads.

Do not grease backs of brake pads sleeve.

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

Turn piston back fully with special tool 34 1 050 DEVICE .

Fig 5: Pressing Piston Using Special Tool (34 1 050)

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Check minimum brake disc thickness:

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

Fig 6: Checking Minimum Brake Disc Thickness Using Special Tool (34 1 280)

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

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

IMPORTANT: Dust boot must not come into contact with brake pad paste as this may cause the dust boot to swell.

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

Fig 7: Identifying Dust Boot And Brake Pad Contact Surface

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

Fig 8: Identifying Brake Pad Contact Surfaces

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

Fig 9: Identifying Brake Caliper Contact Surface

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So as not to damage the surface coating, if possible do not mechanically clean the guide surfaces (1) for the brake pads on the brake caliper mounting bracket.

Instead, clean with brake cleaner and apply a thin coating of brake pad paste.

Fig 10: Identifying Brake Pad Guide Surface

Courtesy of BMW OF NORTH AMERICA, INC.

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.