34 21 200 Removing and installing/replacing both brake pads of rear disc brakes

WARNING: This page is about a different car, the 2013 BMW 550i GT, 2012 BMW 550i GT, 2011 BMW 550i GT, and 2010 BMW 550i GT. However, it is still accessible from the selected car via links, so may be relevant.

Special tools required:

34 1 050
34 1 280

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 work

Remove WHEELS .
Remove BRAKE PAD WEAR SENSOR .

NOTE: After completing repair 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 BREAKING IN NEW BRAKE DISCS/BRAKE PADS .
If necessary, when replacing pads, reset CBS display in accordance with factory specification.

Lift out retaining spring (1).

Fig 1: Lifting Retaining Spring

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Remove cover plug (1).

Fig 2: Identifying Cover Plug

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Unscrew guide bolts (1).

Withdraw brake caliper backwards.

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

Installation note:

Tightening torque 34 21 4AZ .

Clean guide screws only; do not grease.

Check threads.

Fig 3: Identifying Guide Bolts

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Replace all guide screws which are not in perfect condition.

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.

Fig 4: Turning Piston Using Special Tool (34 1 050)

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

Remove outer brake pad.

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

Clean brake pads.

Do not grease backs of brake pads sleeve.

Fig 5: Removing Outer Brake Pad

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Check minimum brake disc thickness:

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

Fig 6: Checking Brake Disc Thickness

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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 Piston Contact Surface

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

Fig 8: Identifying Brake Caliper Housing Contact Surface

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Clean contact surface (3) 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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Fig 10: Locating Brake Pads Guide Surfaces On Brake Caliper Mounting Bracket

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