GM Service Manual Online
For 1990-2009 cars only

Tools Required

J 7872 Magnetic Base Dial Indicator Set, or equivalent

  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove the torque tube assembly from the vehicle. Refer to Driveline Torque Tube Replacement in Rear Drive Axle.
  3. Clean the surface of the first 25 mm (1 in) of the differential pinion input shaft splines from the end of the shaft.
  4. Mount a dial indicator set, J 7872 , or equivalent, and position the dial indicator to contact the differential pinion input shaft splines approximately 13 mm (½ in) from the end of the shaft.
  5. Rotate the differential pinion input shaft by hand to locate the low spot.
  6. Set the dial indicator to zero on the low spot.
  7. Rotate the differential pinion input shaft by hand and record the amount of radial runout.
  8. Compare the runout of the differential pinion input shaft to the following specification:
  9. Specification
    Differential pinion input shaft maximum allowable runout 0.05 mm (0.002 in).

  10. If the differential pinion input shaft runout exceeds the specification, the differential pinion assembly requires replacement.