Mark the position of the wheel disk on the wheel hub with paint. This ensures that the balanced wheel can be reinstalled in its original position.
Loosen the wheel nuts on the vehicle while it is on the ground.
Raise the front of the car, see item 29.
Remove the wheel.
Measure the thickness of the brake disc. In workshops, a special caliper or a caliper with a micrometer is used for this, since when the brake disc wears out, a protrusion forms on its edge. The thickness of the brake disc can also be measured with a regular caliper, but in this case, spacers of a known thickness should be placed on both sides of the disc and the thickness of the two spacers should be subtracted from the measured value.
Attention: Measure at least 4 points on the brake disc.
If the wear limit is reached, replace the brake disc. Wear limit values, see paragraph 18.17.
If there are significant scratches and grooves deeper than 0.5 mm, replace the disc.
If you have a dial indicator, measure the lateral runout of the brake disc. Set the dial indicator at a distance of 5 mm from the edge. Required value: maximum 0.15 mm. Too much lateral runout can be caused by a broken front wheel bearing; visit a service station to check.
Give away the wheel nuts.
Position the wheels according to the markings, screw in the wheel nuts. Lower the car and tighten the nuts crosswise. Tightening force see item 19.4.