Rear Axle Circular Flange Runout Check
8.8 INCH RING GEAR/E-SERIES/F-150 AND BRONCO IN LATE PRODUCTIONFIG. 13 Pinion Bearing Torque Preload Check (Circular Flange Shown):
FIG. 14 Lateral Runout Check:
FIG. 15 Companion Flange Combined Runout Chart:
1. Raise the vehicle on a hoist that supports the rear axle (twin post hoist).
2. Remove the driveshaft assembly.
3. Check the circular flange for damage.
4. To check radial runout, set up dial indicator.
5. Rotate the circular flange with the dial indicator in place. If the runout exceeds specifications, remove the flange and install it 180° from original position.
FIG. 13 Pinion Bearing Torque Preload Check (Circular Flange Shown):
CAUTION: BEFORE removing the circular flange, check and record the pinion nut torque. Also, check and record the pinion bearing preload, (Fig. 13). Original readings must be repeated after the circular flange is repositioned.
Under no circumstances should the pinion nut be backed off to reduce preload. If reduced preload is required, a new collapsible pinion spacer and pinion nut must be installed.
6. If runout is still excessive, remove and install flange an additional 90 degrees and check runout.
7. To check lateral (face) runout, set up the dial indicator. Repeat Steps 5 and 6.
8. If runout is still excessive, replace companion flange and check runout. If necessary, rotate the new flange on the pinion shaft until an acceptable runout is obtained.
If excessive runout is still evident after replacement of the circular flange, it will be necessary to replace the ring and pinion gear, and repeat the above checks until runout is within specifications.
9. Install the driveshaft assembly as described in General Driveshaft Service and Driveshaft-Double Cardan-Type U-Joint.