BMW X3 Service & Repair Manual: Removing and installing/renewing brake pads on both front disc brakes

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 pins and expanding 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 (3 g) or 83 19 2 158 852 (100 g). Spread brake pad paste onto the marked surfaces using a brush!

Necessary preliminary tasks:

• Remove FRONT 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.
• When replacing pads, reset CBS display in accordance with factory specification.

Lever out retaining spring (1) in direction of arrow towards rear.

Remove plastic plugs (1).

Unscrew guide bolts (1).

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

Withdraw brake caliper backwards.

Installation note: Only clean guide bolts; do not grease.

Check thread.

Replace all guide screws which are not in perfect condition.

IMPORTANT: Piston-side brake pad is installed directional! Pay attention to direction-of-rotation arrow!

Mark any worn brake pads.

Remove brake pads in direction of arrow.

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.

IMPORTANT: When forcing piston back:

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

Press back brake pads and piston with special tool 34 1 050.

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 fitted if the brake disk thickness is greater than the MINIMUM BRAKE DISC THICKNESS (MIN TH).

Check dust boot for damage and renew if necessary.

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

Clean contact surface (1) 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 (1) for the brake pads on the brake caliper mounting bracket. Clean guide surfaces (1) 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 (1 and 2) for the brake pads on the brake caliper mounting bracket. Clean guide surfaces (1 and 2) with brake cleaner and apply a thin coating of brake pad paste.

Lightly coat the T-head of the inner brake pad with brake pad paste in area (1 and 2).

Lightly coat the T-head of the outer brake pad with brake pad paste in area (1 and 2).