Ford 8.8-Inch Ring Gear - Rear Drive Axle/Differential

Differential Case








Removal
1. Remove the axle shafts.

2. NOTE: Inspect the removed lubricant for metallic particles which indicate wear or damage.

Wipe the lubricant from the internal working parts and inspect the parts for wear and damage.
3. Rotate the differential assembly to check for roughness indicating bearing/gear damage.





4. NOTE: Mark the position of the bearing caps, as the arrows may not be visible. Always install the bearing caps in their original locations and positions.

Remove the 4 bolts and the 2 bearing caps.





5. CAUTION: Place a wood block between the pry bar and the differential housing to protect the machined surface or damage to the component may occur.

Using a pry bar and a wood block, remove the differential assembly from the differential housing.





6. Remove and discard the 10 ring gear bolts.





7. NOTE: Do not damage the differential ring gear bolt hole threads.

NOTE: If removing the anti-lock speed sensor ring, discard it, and install a new anti-lock speed sensor ring during installation.

Insert a punch in the bolt holes and drive off the differential ring gear and, if necessary, the anti-lock speed sensor ring.





8. Position the differential assembly, including the differential bearing cups and differential bearing shims, in the differential housing. Install the 2 bearing caps and the 4 bolts.
^ Tighten to 112 Nm (83 lb-ft).

9. Position the special tool.
1 Rotate the differential case to verify that the differential bearings have seated correctly.
2 Position the special tool.





10. Measure and note the differential case runout.
^ If the runout does not exceed the specification, install a new differential ring gear and pinion.
^ If the runout exceeds the specification, the differential ring gear is true and the concern is due to either differential case/differential bearing damage. Proceed as follows.





11. Remove the 4 bearing cap bolts, the 2 bearing caps and the differential assembly from the axle housing.
12. Using the special tools, remove the differential bearings.





13. Using the special tool, install the new differential bearings.
1 Position the bearing.
2 Using the special tool, press the bearings on the differential case.





14. Position the differential assembly, including the differential bearing cups and differential bearing shims in the differential housing. Tighten bearing caps to 112 Nm (83 lb-ft).





15. Position the special tool.
1 Rotate the differential case to verify that the differential bearings have seated correctly.
2 Position the special tool.





16. Measure the differential case runout.
^ If the runout does not exceed the specification, use the new differential bearings for assembly.
^ If the runout exceeds the specification, install a new differential case.





17. Remove the 4 bearing cap bolts, the 2 bearing caps and the differential assembly from the axle housing.

Installation

Assembly
1. Position the differential ring gear, the anti-lock speed sensor ring and the differential case. Align the bolt holes by starting 2 bolts through the holes in the differential case and the differential ring gear. Press the new anti-lock speed sensor ring, if removed, and the differential ring gear on the differential case.
2. Install the 10 new differential ring gear bolts.
^ Tighten to 105 Nm (77 lb-ft).





3. With the pinion depth set and pinion installed, place the differential assembly in the differential housing.





4. Install a differential bearing shim on the left side.





5. NOTE: Always install the bearing caps in their original locations and positions.

NOTE: Apply pressure toward the left side to make sure the left differential bearing cup seats correctly.

Install the left bearing cap and loosely install the 2 bolts.





6. Install progressively larger differential bearing shims, on the right side until the largest shim selected is installed by hand.





7. Install the right side bearing cap and tighten the 2 left side and 2 right side bolts.
^ Tighten to 112 Nm (83 lb-ft).





8. Rotate the differential case to make sure it turns freely.





Measuring backlash
9. Using the special tools, measure and note the differential ring gear backlash.
^ If backlash is within the specification, refer to Backlash within specification in this procedure.
^ If a zero backlash condition occurs, refer to Zero backlash in this procedure.
^ If backlash is not within the specification, refer to Backlash not within specification in this procedure.








Zero backlash
10. If a zero backlash condition occurs, add 0.51 mm (0.020 inch) to the RH side and subtract 0.51 mm (0.020 inch) from the LH side to allow backlash indication. Measure the backlash. Refer to Measuring backlash in this procedure.





Backlash not within specification
11. To increase or decrease backlash, remove the bearing caps and install a thicker shim and a thinner shim accordingly.
^ If backlash is not within the specification, increase the thickness of one differential bearing shim and decrease the thickness of the other differential bearing shim by the same amount.





12. Rotate the differential assembly several times to verify that the differential bearings seated correctly.





13. Using the special tools, recheck the backlash.
^ If backlash is within the specification, refer to Backlash within specification in this procedure. If backlash is not within the specification, repeat Backlash not within specification in this procedure.





Backlash within specification
14. Remove the 4 bolts and the 2 bearing caps.
15. To establish differential bearing preload, increase both left and right differential bearing shim sizes by the specification shown.





16. Using the special tool, fully seat the differential bearing shims. Make sure the assembly rotates freely.





17. Install the 2 bearing caps and 4 bolts.
^ Tighten to 112 Nm (83 lb-ft).





18. Using the special tools, recheck the backlash.





19. Install the axle shafts.