Removal and Installation

Part 1 Of 2:

Removal
1. Remove the differential housing cover and drain the rear axle.
2. Remove the axle shafts.
3. Wipe the lubricant from the internal working parts and visually inspect the parts for wear or damage.





4. Rotate the differential case to see if there is any roughness which would indicate damaged bearings or gears.





5. NOTE: There is a space between the anti-lock speed sensor ring and the ring gear for measuring ring gear back face runout.

Position the special tool and inspect ring gear backlash and ring gear back face runout.





6. CAUTION: Mark the position of the bearing caps, as arrows may not be visible. The bearing caps must be installed in their identical locations and positions.

Loosen the differential case.
1 Remove the four bearing cap bolts.
2 Remove the two bearing caps.





7. WARNING: Be careful not to allow the differential case to fall.

CAUTION: Place a wood block between the pry bar and the rear axle housing to protect the machined surface from damage.

Using pry bars and the wood blocks, remove the differential case from the rear axle housing.





8. Remove the 10 ring gear bolts.





9. CAUTION: Care should be taken not to damage the ring bolt hole threads.

NOTE: The anti-lock speed sensor ring cannot be reused once removed.

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





10. Install the differential case.
- Position the differential case assembly, including the bearing cups and shims, in the rear axle housing. Install the differential bearing caps and the differential bearing cap bolts.





11. Position the special tool.
1 Rotate the differential case to ensure the differential bearings are correctly seated.
2 Install the special tool.





12. NOTE: If runout is less than specification, install a new ring gear and pinion. If runout exceeds specification, the ring gear is true and the concern is due to either a damaged differential case or differential bearings. Inspect the differential bearings. If the differential bearings are not damaged, replace both the differential case and the differential bearings.

Measure the differential case runout without the ring gear.
1 Rotate the differential case.
2 Check and note the differential case runout.





13. Remove the differential case from the rear axle housing and remove the differential bearings using the special tools.





14. Using the special tool install the new differential bearings on the differential case.





15. Install the differential case. Position the differential case assembly, including the bearing cups and shims in the rear axle housing. Tighten bearing caps to specifications.





16. Measure the differential case runout without the ring gear, and check the case runout again with the new differential bearings.
- If the runout is now less than the specification shown, use the new differential bearings for assembly.
- If the runout is still excessive, the differential case is damaged and must be replaced.

Installation





1. CAUTION: Make sure that the notches on the case flange and the anti-lock speed sensor ring are aligned.

Press a new anti-lock speed sensor ring, if removed, and the ring gear on the differential case.
- Align the notch on the differential case flange with the notch on the anti-lock speed sensor ring,





2. Install the ring gear bolts.
- Apply Stud and Bearing Mount E0AZ-19554-BA or equivalent meeting Ford specification WSK-M2G349-A1 to ring gear bolts.





3. With pinion depth set and pinion installed, place the differential case in the rear axle housing.





4. Install a shim on the left side.





5. CAUTION: Mark the position of the bearing caps as arrows may not be visible. The bearing caps must be installed in their identical locations and positions.

NOTE: Apply pressure toward the left side to make sure the left bearing cap is seated.

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





6. Install progressively larger shims on the right side until the largest shim selected can be assembled by hand.





7. Install the right side bearing cap and tighten the left side and right side bolts to specification.





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








9. Using the special tool, measure the ring gear backlash.
- If the backlash is within specification, go to Step 14.
- If a zero backlash condition occurs, go to Step 10.
- If the backlash is not within specification, go to Step 11.

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. Check the backlash. Repeat Step 9.





11. To increase or decrease the backlash, remove the bearing caps and install a thicker shim or a thinner shim as shown.
- If the backlash is not within specification, correct by increasing the thickness of one differential bearing shim and decreasing the thickness of the other differential bearing shim by the same amount.





12. Rotate the differential several times to make sure the differential bearings are correctly seated.





13. Using the special tool, recheck the backlash.
- If the backlash is within specification, go to Step 14. If the backlash is not within specification, repeat Step 9.





14. Remove the bearing caps and bolts.
- To establish differential bearing preload, increase both left and right shim sizes by the specification.
- Use the special tool to ensure that the differential bearing shims are fully seated and the assembly turns freely.





15. Install the bearing caps and bearing cap bolts.





16. Using the special tool, recheck the backlash.
17. Install the axle shafts.