GM Service Manual Online
For 1990-2009 cars only

Brake Rotor Lateral Runout Check Front Wheel

Check the rotor for lateral runout using the following procedure:

Tools Required

J 8001 Dial Indicator Set

  1. Remove the tire and the wheel. Refer to Wheel Removal in Tires and Wheels
  2. Tighten the wheel nuts so that the rotor is tight against the hub (JC1 system only).
  3. Adjust the wheel bearings in order to eliminate excessive free play (RWD pickups only). Refer to Wheel Bearing Adjustment in Front Suspension.
  4. Clean the rotor surface.

  5. Object Number: 177668  Size: SH
  6. Install the J 8001 Dial Indicator so that the dial indicator button contacts the rotor surface about 25 mm (1.0 in) from the outer edge.
  7. Set the dial indicator to zero.
  8. Turn the rotor one complete revolution and observe the lateral runout on the dial indicator. The total indicator runout (TIR) should not exceed 0.08 mm (0.003 in).
  9. If lateral runout is not within specifications refinish or replace the rotor (JM3 system only).
  10. In some cases, excessive lateral runout can be rectified by indexing the rotor. Move the rotor one or two wheel bolt positions from the original position (JC1 system only).
  11. If the lateral runout still exceeds 0.08 mm (0.003 in), check the hub for excessive lateral runout, or looseness (JC1 system only).
  12. 10.1. Remove the brake rotor. Refer to Brake Rotor Replacement
    10.2. Reposition the J 8001 Dial Indicator so that the button contacts the surface of the hub.
    10.3. Set the dial indicator to zero.
    10.4. Rotate the hub one complete revolution.
    10.5. Note the lateral runout.
    10.6. If the hub lateral runout exceeds , replace the hub. Refer to Front Wheel Hub, Bearing, and Seal Replacement in Front Suspension.
    10.7. If the hub lateral runout is within specifications, refinish or replace the rotor. Refer to Brake Rotor Refinishing .

Brake Rotor Lateral Runout Check Rear Wheel

Check the rotor for lateral runout using the following procedure:

Tools Required

J 8001 Dial Indicator Set

  1. Remove the tire and the wheel. Refer to Wheel Removal in Tires and Wheels.
  2. Tighten the wheel nuts so that the rotor is tight against the axle flange.
  3. Clean the rotor surface.

  4. Object Number: 325080  Size: SH
  5. Install the J 8001 Dial Indicator so that the dial indicator button contacts the rotor surface about 13 mm (0.5 in) from the outer edge.
  6. Push in the rear axle while setting the dial indicator to zero.
  7. While maintaining the inward pressure, turn the rotor one complete revolution.
  8. Observe the lateral runout on the dial indicator. The total indicator runout (TIR) should not exceed 0.10 mm (0.004 in).
  9. In some cases, excessive lateral runout can be rectified by indexing the rotor. Move the rotor one or two wheel bolt positions from the original position.
  10. If the lateral runout still exceeds 0.10 mm (0.004 in), check the rear axle shaft flange for excessive lateral runout, or looseness.
  11. 9.1. Remove the brake rotor. Refer to Brake Rotor Replacement .
    9.2. Reposition the J 8001 Dial Indicator so that the button contacts the surface of the axle shaft flange.
    9.3. Push the axle shaft flange inward while turning the axle shaft flange one full revolution.
    9.4. Continue pushing in the axle shaft flange while setting the dial indicator to zero.
    9.5. While maintaining the inward pressure, rotate the axle shaft flange one complete revolution.
    9.6. Note the lateral runout.
    9.7. If the axle shaft flange lateral runout exceeds 0.05 mm (0.002 in), replace the rear axle shaft. Refer to Rear Axle Shaft Replacement in Rear Drive Axle.
    9.8. If the axle shaft flange lateral runout is within specifications, refinish or replace the rotor. Refer to Brake Rotor Refinishing .