Removal and Installation

Special Tools:

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 and damage.





4. Rotate the differential case to check for roughness indicating bearing/gear damage.





5. Using a suitable dial indicator and the special tool, check the ring gear backlash and ring gear backface runout.

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





Loosen the differential case.
1. Remove the 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.





Use a pry bar and a wood block to remove the differential case from the rear axle housing.





8. Remove the 10 bolts.

9. CAUTION: Take care not to damage the ring bolt hole threads.





Insert a punch in the bolt holes and drive off the ring gear.





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





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





12. Measure the differential case runout.
1. Rotate the differential case.
2. Note the runout.
^ If the runout is less then the specification, replace the ring gear and pinion. Proceed to Installation.
^ If the runout exceeds the specification, the ring gear is true and the concern is due to either differential case/differential bearing damage. Proceed as follows.

13. CAUTION: Install new differential bearings if replacing the differential case.

Remove the differential case from the axle housing, and inspect the differential case and bearings.
^ If new bearing installation is necessary, proceed as follows. Otherwise, proceed to Installation.





14. Using the special tools, remove the differential bearings.





15. Using the special tool, install the new differential bearings.





16. Install the differential case.
1. Position the differential case assembly, including the bearing cups and shims in the rear axle housing.
2. Install the bearing caps and bolts.





17. Measure the differential case runout. If the runout is now less than the specification shown, use the new differential bearings for assembly. If the runout is still excessive, install a new differential case.
18. Remove differential case from the axle housing.

Installation
All vehicles





1. Press the ring gear on the differential case.





2. Install the bolts.
^ Apply Stud and Bearing Mount EOAZ-19554-BA or equivalent meeting Ford specification WSK-M2G349-A1 to the bolt threads.





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





4. Install a (nominal) shim on the left side.

5. CAUTION: Always install the bearing caps in their identical locations and positions.

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





Install the left bearing cap and loosely install the bolts.





6. Install progressively larger shims on the right side until the largest shim selected is installed 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 turns freely.
Measuring backlash





9. Using the special tool measure the ring gear backlash.
^ If backlash is within the specification, go to Backlash within specification. The specification shown is the full allowable range. For the preferred range, refer to Specifications.
^ If a zero backlash condition occurs, go to Zero backlash.





^ If backlash is not within the specification, go to Backlash not within specification.
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. Check the backlash. Repeat Measuring backlash.
Backlash not within specification





11. To increase or decrease the backlash, remove the bearing caps and install a thicker shim and 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 several times to verify the differential bearings have seated correctly.





13. Using the special tool recheck the backlash.
^ If backlash is within the specification, go to Backlash within specification. The specification shown is the full allowable range. For the preferred range, refer to Specifications.
^ If backlash is not within the specification, go to Backlash not within specification.
Backlash within specification








14. Remove the bearing caps and bolts.
1. To establish differential bearing preload, increase both left and right shim sizes by the specification shown in the illustration.
2. Using the special tool, fully seat the differential bearing shims. Make sure the assembly rotates freely.





15. Install the bearing caps and bolts.





16. Using the special tool recheck the backlash.
17. Install the axle shafts.
18. Install the differential housing cover and refill the rear axle with specified lubricant.