Checking the thickness of the brake disc (Audi A3 8L)

1. Mark the position of the wheels relative to the hub with paint. This will allow you to install the balanced wheel in its original position during assembly. Loosen the wheel mounting bolts on the car standing on the ground. Raise the car and place it on stands. Remove the wheels.



2. The thickness of the brake disc must always be measured at its thinnest point. Service stations use a special caliper or micrometer clamp for this, since a ridge forms as a result of wear on the brake disc. You can measure the thickness of the brake disc using a regular caliper. To do this, place a lining of the appropriate thickness on each side of the disc (for example, a coin). Then the thickness of the linings must be subtracted from the value obtained as a result of the measurement.

Warning: It is necessary to measure the disc thickness at several points.

3. The dimensions of the brake discs are given in the Specifications.

4. When the wear limit is reached, the disc must be replaced.

5. If there are large cracks or burrs deeper than 0.5 mm, the disc must be replaced.

6. Install the wheels so that the markings applied when removing the wheels match. Tighten the wheel mounting bolts. Lower the car onto the wheels. Tighten the mounting bolts crosswise to 120 Nm. Do not lubricate the wheel mounting bolts.

[Information obtained from this resource «audimanual.ru»]