Runout Check

WARNING: The electrical power to the air suspension system must be shut off prior to hoisting, jacking or towing an air suspension vehicle. This can be accomplished by turning off the air suspension switch. Failure to do so can result in unexpected inflation or deflation of the air springs, which can result in shifting of the vehicle during these operations.

CAUTION: Pinion bearing preload must be reset if the pinion nut has been loosened or removed for pinion flange reindexing or installation.

1. Raise the vehicle on a twin-post hoist that supports the rear axle.
2. Remove the driveshaft.
3. Check the pinion flange for damage.





4. Position Companion Flange Runout Gauge on the pinion flange.





5. Position the Clamp Plate onto the Companion Flange Runout Gauge.





6. Align the holes on the clamp plate with the holes in the pinion flange and install the bolts. Snug the bolts evenly.





7. Position the Dial Indicator/Magnetic Base as shown. Turn the Companion Flange Runout Gauge, and locate and mark the high spot on the pinion flange with yellow paint.
If the flange runout exceeds 0.25 mm (0.0 10 inch), remove the pinion flange, reindex the flange one-half turn on the pinion, and reinstall it.





8. Check the runout again. If necessary, rotate the flange until an acceptable runout is obtained. If the flange runout is still more than 0.25 mm (0.0 10 inch), replace the pinion flange.
9. If excessive runout is still evident after installation of the pinion flange, install a new ring and pinion. Repeat the above checks until the runout is within specifications.
10. Install the driveshaft.