Brake Rotor/Disc: Service and Repair

1. If the run-out of the brake disc is equivalent to, or exceeds the limit specification, change the phase of the disc and hub, and then measure the run-out again.
2. Before removing the brake disc, chalk both sides of the wheel stud on the side at which run-out is greatest.

Measure Play With Dial Gauge:

3. Remove the brake disc, and then place a dial gauge as shown in the illustration; then move the hub in the axial direction and measure the play. The limit is 0.05 mm (0.0020 inches)
- If the play is equivalent to or exceeds the limit, disassemble the hub knuckle and check each part.
- If the play does not exceed the limit specification, install the brake disc at a position 180� away from the chalk mark, and then check the run-out of the brake disc once again.
4. If the run-out cannot be corrected by changing the phase of the brake disc, replace the brake disc or turn rotor with an on the car type brake lathe (Accuturn-8750, or equivalent). Be sure to follow the exact brake lathe manufacturer instructions. Rotors turned on the vehicle will often have a lower run-out than a new disc.