Measuring Backlash

WARNING: This page is about a different car, the 2003 GMC Sonoma, 2003 GMC Jimmy, 2003 Chevrolet S10 Pickup, and 2003 Chevrolet Blazer. However, it is still accessible from the selected car via links, so may be relevant.

Install a dial indicator so the button contacts the outer edge of the pinion yoke.
Ensure that the plunger is at a right angle to the pinion yoke.
Move the pinion yoke back and forth through the pinion flange's free play while not allowing the ring gear to move.
Record the dial indicator reading.
To determine the actual backlash, divide the dial indicator reading by 2.
An actual dial indicator reading of 0.16 mm (0.006 in) means that there is actually 0.08 mm (0.003 in) backlash.

Specification

The backlash between the ring gear and the drive pinion should be between 0.08-0.25 mm (0.003-0.010 in) with a preferred specification of 0.13-0.18 mm (0.005-0.007 in).

Important: When adjusting the backlash, observe the following:
- Always turn the left and the right differential adjuster nut sleeves in equal amounts.
- Turning the differential adjuster nut sleeves one notch will change the backlash about 0.08 mm (0.003 in).
- Once the proper backlash is obtained, turn the left differential adjuster nut sleeve in one additional notch in order to preload the differential case side bearings.
  
  Fig 1: Installing A Dial Indicator So Button Contacts Outer Edge Of Pinion Yoke
  Courtesy of GENERAL MOTORS CORP.
If the backlash is too small, use the following procedure to adjust:
1. Increase the backlash by turning the left differential adjuster nut sleeve in one notch and the right differential adjuster nut sleeve out one notch.
2. Recheck the backlash and adjust as necessary.
If the backlash is too large, use the following procedure to adjust:
1. Decrease the backlash by turning the right differential adjuster nut sleeve in one notch and the left differential adjuster nut sleeve out one notch.
2. Recheck the backlash and adjust as necessary.
Once the proper backlash is obtained, turn the left differential adjuster nut sleeve in one additional notch using the J 42213 in order to preload the differential case side bearings.
Recheck the backlash and adjust as necessary.