BMW X5: Overview Of Front Brakes

Fig. 17: Identifying Front Brake Components

1. Brake disc
2. Brake caliper
3. Brake-pad wear sensor
4. Brake pads
5. Pulse generator
6. Brake hose
7. Brake guard plate
8. Checking thickness of brake pad

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).

Necessary preliminary tasks:

• Remove wheels
• Remove brake pad wear sensor

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

Installation:

Attach retaining spring (1) first at top and bottom on brake caliper and then allow to engage in recesses of brake caliper housing.

Fig. 18: Removing Retaining Spring

Remove plastic plugs (1).

If necessary, when replacing linings, reset CBS display in accordance with factory specification.

Release guide screws (2) with special tool 34 1 080. See 34 1 080 BIT INSERT. Withdraw brake caliper backwards.

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

Fig. 19: Identifying Plastic Plugs

Left:

Pull brake lining wear sensor (1) towards rear out of lining.

If necessary, replace brake lining wear sensor.

Installation:

Only clean guide screws; do not grease.

Check threads.

Replace all guide screws which are not in perfect condition.

Tightening torque 34 11 4AZ.

Fig. 20: Pulling Brake Lining Wear Sensor

Remove outer brake pad (1) in direction of arrow.

Force inner brake pad (2) in direction of arrow off piston and remove.

The inner brake pad is seated with a spring in the piston or in the brake caliper housing.

IMPORTANT: Mark any worn brake linings.

In the event of one-sided brake lining wear, do not change brake linings round.

Observe minimum thickness of brake pads.

Clean brake linings.

Do not apply grease to brake pad backplate.

Fig. 21: Removing Outer Brake Pad

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.

Fig. 22: Identifying 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.

New brake linings may only be installed if the brake disc thickness is greater than or equal to the minimum brake disc thickness (MIN TH).

Fig. 23: Identifying Special Tool (34 1 280)

Check dust sleeve (2) for damage and replace if necessary.

Clean contact face (1) of brake piston and apply a thin coating of anti-squeak compound.

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

Fig. 24: Identifying Dust Sleeve

Clean mounting faces (1) and (2) of brake lining hammer heads/brake caliper housing and coat with Plastilube.

NOTE: Grease contact surfaces on brake caliper at top and bottom.

Fig. 25: Identifying Mounting Faces And Brake Lining Hammer Heads

Clean mounting face (1) of brake caliper and apply a thin coating of Plastilube.

Fig. 26: Identifying Mounting Face Of Brake Caliper

Clean hammerhead guides (1) and apply a thin coating of Plastilube.

Fig. 27: Identifying Hammerhead Guides

NOTE: After completing work:

• Fully depress brake pedal several times so that brake linings contact brake discs.
• When installing new brake linings 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.

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