Assembly

CAUTION: Always install new gaskets and seals when assembling the axle. When building the subassembly, lubricate each component with clean Motorcraft SAE 80W90 Thermally Stable 4x4 Axle Lubricant meeting Ford specification WSP-M2C197-A.Also,lubricate the subassembly when installing it into the differential housing. Tighten all fasteners to specification.

1. CAUTION: Always install new differential pinion bearings when installing new differential drive pinion bearing cups.

Lubricate the new differential drive pinion bearing cups.
- Use Motorcraft SAE 80W90 Thermally Stable 4x4 Axle Lubricant meeting Ford specification WSP-M2C197-A.





2. Using the special tools, install the differential drive pinion bearing cups.





3. Note: Apply a light film of oil to the differential pinion bearings before installing them.

Assemble and position the following in the differential housing.
1. Position the Screw.
2. Position the Aligning Adapter.
3. Position the inner differential pinion bearing.
4. Position the Gauge Disc.
5. Position the Gauge Block.
6. Position the outer differential pinion bearing.
7. Thread on the Handle.





4. Using a Nm (pound-inch) torque wrench, tighten the Handle.





5. Note: Offset the Gauge Block to obtain an accurate reading.

Rotate the Gauge Block several half turns to ensure the differential pinion bearings seat correctly, and position the Gauge Block as shown.





6. Install the special tool and the paper shipping tags.
1. Position the special tool and the paper shipping tags.
2. Install the differential bearing caps.
3. Install the bolts.





7. Note: Use a feeler gauge, or flat, clean drive pinion position shims as a measuring device.

Note: Selection of a shim that is too thick results in deep tooth contact at final assembly. Do not attempt to force the gauge or shim between the Gauge Block and the Gauge Tube. A slight drag indicates a correct selection.

Using a feeler gauge, or a flat, clean drive pinion position shim, measure between the Gauge Block and the Gauge Tube. Record the measurement.
- Remove the special tools after determining the correct shim thickness.





8. Select the correct thickness drive pinion position shim.
- New drive pinion position shims are available in 0.762 mm (0.030 inch), 0.8128 mm (0.032 inch), 0.8636 mm (0.034 inch),0.9144 mm (0.036 inch), 0.9652 mm (0.038 inch),1.016 mm (0.040 inch), 1.0668 mm (0.042 inch),1.1176 mm (0.044 inch), 1.1684 mm (0.046 inch), 1.2192 mm (0.048 inch), 1.27 mm (0.050 inch), and 1.3208 mm (0.052 inch) thickness.








- If installing a new gearset, notice the plus (+), minus (-), or zero (O) etching on both the original and the new drive pinion, and adjust the thickness of the new shim according to the following charts.





9. Install the pinion position shim and the differential pinion bearing.
- Using the special tool and a suitable press, seat the differential pinion bearing firmly against the pinion position shim.





10. Install a new collapsible spacer.





11. Install the differential pinion bearing and the front axle drive pinion shaft oil slinger.





12. CAUTION: Installing the pinion seal without the correct tool can result in early seal failure.

CAUTION: If the pinion seal becomes cocked during installation, remove it and install a new one.

Using the special tool, install the pinion seal.
13. Lightly lubricate the pinion gear splines.
- Use Motorcraft SAE 80W90 Thermally Stable 4x4 Axle Lubricant meeting Ford specification WSP-M2C197-A.





14. Position the pinion gear in the differential housing.





15. CAUTION: Never use a metal hammer on the pinion flange or install the flange with power tools. If necessary, use a plastic hammer to tap on a tight fitting flange.

Align the index marks and install the pinion flange.





16. Install the new nut hand-tight.





17. CAUTION: Do not loosen the nut to reduce preload. Install a new collapsible spacer and nut if preload reduction is necessary.

Use the special tool to hold the pinion flange while tightening the nut to set the preload.
- Rotate the pinion occasionally to ensure the differential pinion bearings are seating correctly. Take frequent differential pinion bearing preload readings by rotating the pinion with a Nm (inch-pound) torque wrench.
- If installing new differential pinion bearings, tighten the nut to specification.
- If installing the original differential pinion bearings, the final reading must be 0.56 Nm (5 inch lbs.) more than the initial reading taken during disassembly.





18. Install the special tool.





19. Install the differential case in the differential housing.





20. Note: Repeat this step until obtaining a consistent reading.

Measure the total end play.
1. Install the special tool.
2. Force the differential case as far as possible away from the indicator. Position the indicator tip on the machined surface and adjust it to measure full travel. With force still applied, set the indicator to zero.
3. Force the differential case as far as possible in the opposite direction.
4. Record the total end play reading on the Differential Bearing Shim Selection Procedure Worksheet, Line A in this procedure.





21. Remove the special tool, and remove the differential case.
1. Remove the special tool.
2. Remove the differential case.





22. Use a fine flat file to remove any burrs and nicks found on the differential ring gear mounting surface.





23. CAUTION: Do not reuse the original bolts.

Using a suitable press, install the differential ring gear.
1. Position the differential ring gear and the differential case. Start two or three new bolts to align the holes in the ring gear and the differential case.
2. Using a suitable press, install the differential ring gear.





24. Install the remaining new bolts. Tighten all of the bolts to specification.





25. Install the special tool, and position the assembly in the differential housing.
1. Install the special tool.
2. Position the assembly in the differential housing.





26. Position the special tool.





27. Force the differential ring gear into mesh with the pinion gear (zero backlash). With force still applied, set the special tool to zero.





28. Force the differential ring gear away from the pinion gear as far as possible. Record the reading on the Differential Bearing Shim Selection Procedure Worksheet, Line D in this procedure.





29. Remove the special tool.





30. Remove the differential case from the differential housing. Remove the special tool from the differential case hubs.
31. Complete the worksheet, and select the appropriate thickness differential shims. New differential shims are available in 0.0762 mm (0.003 inch), 0.127 mm (0.005 inch), 0.254 mm (0.010 inch), and 0.762 mm (0.030 inch) thickness.





Differential Bearing Shim Selection Procedure Worksheet





32. Install the differential shims and the differential bearing.
1. Position the differential shims and the differential bearing.
2. Using a suitable press, install the differential bearing.
- Repeat this step for opposite side of the differential case.





33. Install the special tools.
- Position the Clutch Housing Alignment Adapter needle in the Housing Spreader Adapter hole.





34. CAUTION: Over spreading can damage the differential housing.

Spread the differential housing to the specification.





35. Remove the special tools.





36. Note: Push the differential case downward to fully seat the differential bearing cups in the differential housing.

Install the differential bearing cups and the differential case in the differential housing.
1. Position the differential bearing cups on the differential bearings.
2. Lower the differential case in place.





37. CAUTION: Do not tighten the bolts to specification at this time.

Install the differential bearing caps in their original positions.
1. Position the differential bearing caps.
2. Install the bolts hand-tight.





38. Remove the special tools.





39. Tighten the bolts.
40. Verify that the differential case rotates freely.





41. Using the special tools, measure the backlash at three equally spaced points on the differential ring gear.
1. Mount the special fool.
2. Position the special tool.
3. Zero the indicator.
4. Turn the differential ring gear without turning the pinion gear. Record the measurement.
- The backlash tolerance is 0.13 mm (0.005 inch) to 0.20 mm (0.008 inch) and cannot vary more than 0.05 mm (0.002 inch) between points checked. A backlash variation of more than 0.005 mm (0.002 inch) indicates gear/case runout.
- 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.





42. Remove the special tools.





43. Check the gear tooth contact pattern.





44. Using the special tools, install the axle tube bearing.





45. Using the special tools, install the axle shaft oil seal.





46. Using the special tools, install the axle shaft bearing.





47. Using the special tools, install the axle shaft oil seal.





48. Install the axle shaft.

49. CAUTION: The machined mating surfaces on the differential housing and the differential housing cover must be clean and free of lubricant before applying the new silicone sealant. Cover the inside of the differential housing before cleaning the machined surface to prevent contamination.

Clean the differential housing and the differential housing cover mating surfaces.





50. Apply a continuous bead of sealant to the differential housing cover.
- Use Ford Black Silicone Rubber F4AZ-19562-B or equivalent meeting Ford specification WSE-M4G323-A1.





51. CAUTION: Install the differential housing cover within 15 minutes of applying the silicone or it will be necessary to apply new sealant. If possible, allow one hour before filling the axle with lubricant to make sure the silicone sealant has cured.

Install the differential housing cover.
1. Position the differential housing cover.
2. Install the bolts.
52. Install the front axle assembly.
53. Fill the axle with 1.54 Liter (2.25 pints) of lubricant.
- Use Motorcraft SAE 80W90 Thermally Stable 4x4 Axle Lubricant meeting Ford specification WSP-M2C197-A.