Removal and installation the front wheel brake disc (BMW 3 Series E46)

Removal

1. Remove the brake guide with the caliper and the pads inserted and tie them to the suspension with wire. Do not disconnect the brake hose, otherwise you will have to bleed the air from the system after installation.



2. Loosen the mounting screw "4" with a socket wrench by 5 mm.

3. Remove the brake disc.

Ventilated brake discs are balanced. Do not remove or move the balancing brackets on the inner diameter of the brake disc.

Installation

To achieve uniform braking on both sides, both brake discs must have the same surface in terms of quality and roughness. Therefore, it is necessary to replace or grind both brake discs.

When checking discs for runout, refer to Specifications for acceptable runout values.

1. Measure the thickness of the brake disc, refer to Section Measuring the thickness of the brake disc.

2. If there is rust on the disc flange and wheel hub, remove it.

3. Clean the new discs from the protective coating with nitro thinner.

4. Install the disc on the hub and rotate it so that the bolt holes align. Tighten the bolts with a socket wrench to 16 N·m.

5. Reinstall the brake caliper with the brake pads inserted, refer to the relevant section.



6. New brake discs should be carefully broken in in three stages. Stage one: Five braking applications from 50 km/h by pressing the brake pedal hard on a road where there is no traffic. Stage two: Allow the brakes to cool. Stage three: Another five braking applications from 50 km/h.