2. Measure the thickness of the brake discs. In workshops, a micrometer or a special caliper is used for this (035), because when worn, a shoulder forms on the edge of the disc. It is possible to measure the thickness of the discs with a conventional caliper, but in this case, a rigid gasket should be used on each side of the brake disc (e.g. 2 coins). To find out the thickness of the disc, subtract the thickness of the gaskets from the readings.
Attention! For more accurate measurements with a micrometer, it is necessary to measure at least eight points on the disk. In this case, the thickness must remain constant within a tolerance of 0.02 mm.
3. When the minimum thickness is reached, the brake linings can be changed again. If the wear limit is reached, replace the brake discs.
4. Cooled brake discs with fine cracks up to 25 mm long, which can occur due to high loads, do not need to be replaced. For large cracks or unevenness deeper than 0.5 mm, replace the discs.
5. Repair of brake discs is not allowed. Both discs on the axle should be replaced.
6. If a dial indicator is available, measure the lateral play of the assembled brake disc. Place the hour indicator of small movements in the center of the braking surface.
Attention! Too much lateral runout may be due to increased clearance in the wheel bearings, therefore, first of all, this clearance should be adjusted. If that doesn't work, replace the brake disc.
7. Align the wheels so that the markings made before removing them match. Screw on the wheels. Remove the car from the supports and tighten the wheel bolts in a crosswise manner with a torque of 110 Nm.