Determining Total Differential Shim Pack
- Ensure drive pinion is out of drive axle housing. On 9 3/4" drive axle, install Master Differential Bearings (D-117
) to differential case. On 10 1/2" and 11" drive axles, install Master Differential Bearings (D-136
) to differential case.
- On all axles, install assembled differential case into drive axle housing. Mount dial indicator on ring gear bolt side of case. See Fig 1.
Courtesy of GENERAL MOTORS CORP.
- Force differential assembly toward dial indicator as far as possible. Preload dial indicator to one half of its travel. Place tip of dial indicator on a machined (flat) differential surface, just next to ring gear bolt. Mark this location with chalk. Reset preloaded dial indicator gauge dial to zero.
- Force differential assembly away from dial indicator as far as possible. Repeat this step until constant indicator reading is obtained. Record number of thousandths that dial indicator traveled. Number is NOT present reading on dial (dial may have gone completely around once).
- This reading determines thickness of shim pack to be used without any bearing preload, which will be added later.
- Remove dial indicator from drive axle housing. Remove differential case from drive axle housing. DO NOT
remove master bearings from differential case assembly at this time. Go to PINION DEPTH ADJUSTMENT .