LEMON Manuals: Even more car manuals for everyone
Home >> GMC >> 2006 >> Sierra 1500 HD, RWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1331 (Rear Drive Axle) >> Repair Instructions >> Backlash Adjustment (10.5/11.5 Inch Axle) >> Adjustment Procedure

Adjustment Procedure

WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
  1. Measure the rotating torque of the drive pinion and differential assembly. Refer to Differential Drive Pinion Gear Bearing Replacement (8.6, 9.5, 11.5 Inch Axle)  or Differential Drive Pinion Gear Bearing Replacement (10.5 Inch Axle) .
    2. Fig 1: Measuring Ring Gear Backlash
    GM6946Courtesy of GENERAL MOTORS CORP.
  2. Install the J 8001:  indicator and the J 25025:  pins to the axle housing.
  3. Place the indicator stem of the J 8001:  indicator at the heel end of a gear tooth.
    4. NOTE: Preload the dial of the J 8001:  indicator approximately a turn and zero the gauge.
  4. Set the J 8001:  indicator so that the stem is aligned with the gear rotation and square to the tooth angle.
  5. Hold the drive pinion stationary, move the ring gear back and forth.
  6. Repeat the measuring procedure at eight points around the ring gear.
  7. The difference between the backlash at all of the measuring points should not vary by more than 0.05 mm (0.002 in).
  8. If the difference between the backlash at all of the measuring points varies by more than 0.05 mm (0.002 in)., inspect for burrs, distorted case flange or uneven bolting.
  9. If the difference between all the measuring points is within specifications, the backlash at the between the ring gear and the drive pinion should be between 0.08-0.25 mm (0.003-0.010 in) with a preferred backlash of 0.13-0.18 mm (0.005-0.007 in) at the minimum lash point.
    10. Fig 2: Turning Adjusters Using J 24429
    GM694535Courtesy of GENERAL MOTORS CORP.
  10. If the backlash is not within specifications, remove the differential bearing adjuster nut retainers bolts.
  11. Remove the differential bearing adjuster nut retainers.
  12. Remove the bearing cap bolts.
    13. NOTE: Before removing the bearing caps, mark the bearing caps left and right.
  13. Remove the bearing caps.
  14. If the backlash is less than, use the J 24429:  spanner to increase the backlash by turning the left differential bearing adjuster in one slot and the right differential bearing adjuster out one slot until the correct backlash is obtained.
  15. If the backlash is greater than, use the J 24429:  spanner to decrease the backlash by turning the right differential bearing adjuster in one slot and the left differential bearing adjuster out one slot until the correct backlash is obtained.
  16. Install the bearing caps.
    17. CAUTION: Refer to Fastener Caution .
  17. Install the bearing cap bolts and tighten to 185 N.m (136 lb ft). for the 10.5 inch axle, or 207 N.m (153 lb ft). for the 11.5 inch axle.
  18. Recheck the backlash following the steps above to verify that the backlash is within specifications.
  19. Install the differential bearing adjuster nut retainers.
  20. Install the differential bearing adjuster nut retainer bolts to tighten to 27 N.m (20 lb ft).
  21. Measure the drive pinion and differential case side bearing preload and adjust, if necessary following the steps above.
  22. Once the backlash and bearing preload is correct, perform a gear tooth contact pattern check in order to ensure proper alignment between the ring and pinion gears. Refer to Gear Tooth Contact Pattern Inspection .
scientia non olet · About LEMON Manuals