The best way to check lateral runout is with the wheels still installed on the vehicle. This gives a much more accurate reading of the Total Indicated Runout under real braking conditions. If equipment is not available to perform the check with the wheels installed, the next best reading can be made with the wheels removed but the caliper still installed.
Important: If the wheel must be removed, re-install the wheel nuts to retain the rotor. Tighten the wheel nuts to the correct torque specification following the proper wheel nut tightening sequence.
- Clean the rotor surface.
- Fasten a dial indicator to the steering knuckle so that the indicator button contacts the rotor surface about 13 mm (0.5 in) from the outer edge.
- Set the dial indicator to zero.
- Turn the wheel one complete revolution and observe the runout indicated on the dial. The Total Indicated Runout must not exceed 0.008 mm (0.003 in).
- If lateral runout exceeds the amount specified in Step 4, refinish or replace the rotor.
In some cases excessive lateral runout of the rotor can be improved by indexing the rotor on the hub one or two bolt positions from the original position. If the lateral runout cannot be corrected by indexing the rotor, check the hub and bearing assembly for excessive lateral runout or looseness. If the hub and bearing assembly lateral runout exceeds 0.06 mm (0.002 in) then replace the hub and bearing assembly. If lateral runout is within specifications then refinish or replace the rotor as necessary.
Important: Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or foreign material from the mating surface of the wheel bearing flange and rotor. Failure to do this may result in increased lateral runout of the rotor and brake pulsation.
