Axle Assembly - In-Vehicle Repair

Special Tools:

Removal
1. Raise the vehicle on a hoist or raise the rear end of the vehicle with a jack. Install safety stands under the frame rails and lower the jack or hoist enough to allow the rear axle to drop into the rebound position for working clearance.
2. Remove the differential housing cover and drain the lubricant from the rear axle.
^ Clean the gasket material from the differential housing cover and the differential housing.

3. Note: An inspection can find the cause of the concern and determine the resolution.

Carry out the following before disassembly.
^ Remove all the lubricant from the internal parts of the conventional differential assembly or Trac-Lok(R) differential assembly. Visually inspect the parts for wear and damage.
^ Rotate the differential assembly to check for any roughness, indicating damaged bearings or gears.
^ Remove all the lubricant and check the differential ring gear and pinion teeth for signs of scoring, abnormal wear, nicks and chips.
^ Use a magnet to search for heavy metal particles indicating component damage.

4. CAUTION: The differential ring gear and pinion must be clean and dry to obtain an accurate reading.

Note: Measure the differential ring gear and pinion backlash at three equally spaced points.

Using the special tools, measure the differential ring gear and pinion backlash.
^ The backlash tolerance is 0.13 - 0.20 mm (0.005 - 0.008 inch) and cannot vary more than 0.05 mm (0.002 inch) between points checked. A backlash variation of more than 0.05 mm (0.002 inch) indicates gear/case runout.
^ Move the differential ring gear toward the pinion to correct high backlash.
^ Move the differential ring gear away from the pinion to correct low backlash.
5. Remove the axle shafts.

6. CAUTION: Index-mark the driveshaft components to maintain driveline balance during assembly.

Disconnect the driveshaft at the rear axle, and position it aside.

7. CAUTION: Note the positions of the mating letters stamped vertically and horizontally on the bearing caps and the differential housing before removing the bearing caps. Matching the letters is important at the time of assembly.

To case removal of the differential assembly, loosen the bolts, then pry the differential case, bearing cups and outboard spacers outward until they are loose in the differential housing.
8. Remove the bolts and the bearing caps.

9. CAUTION: Do not spread the differential housing more than specified.

Using the special tools, spread the differential housing to the specification. Remove the Dial Indicator with Magnetic Base.

10. CAUTION:
^ It will be necessary to use large pry bars to remove the differential assembly from the differential housing. Do not damage the differential ring rear when carrying out this step.
^ Mark or tag the differential bearing cups, indicating from which side they were removed.

Remove the differential assembly with the bearing cups.
^ Remove the special tool after removing the differential assembly.
^ Inspect the differential bearing cups for deep scores, galling and spalling. Discard them if necessary.

11. CAUTION: Mark or tag the outboard spacer(s) indicating from which side they were removed.

Remove the outboard spacer(s).
^ Inspect the spacer(s) for nicks, bending and grooved conditions. Discard them if necessary.

12. CAUTION: Index-mark the pinion flange to the pinion shaft prior to removal.

Use a suitable tool to prevent the flange from turning, and remove the lock nut and washer.

13. Using the special tool, remove the pinion flange.

14. Note: There are drive pinion bearing preload shims on the spline-end of the pinion. These shims can stick to the pinion, the pinion bearing or they can fall out of the differential housing. Collect and keep the shims for reassembly.

Using a soft faced hammer and the special tool, tap the pinion out of the pinion bearing cup and remove it through the rear of the differential housing.

15. Using the special tools, remove and discard the pinion seal.
16. Remove the oil slinger and the pinion bearing.

17. CAUTION: Do not nick the differential housing bore.

Using the special tools, remove the outer pinion bearing cup.

18. Using the special tools, remove the inner pinion bearing cup.

19. The oil slinger, if so equipped, is part of the total drive pinion position shim height required to correctly set pinion depth. Keep the oil slinger intact for assembly.

20. Using the special tools, remove the inner pinion bearing.

21. Note: Discard the drive pinion position shim if bent or nicked. If discarding the shim, measure and record the shim thickness.

Remove the oil slinger, if so equipped, and the drive pinion position shim.
22. Carry out the following after disassembling the axle:
^ Thoroughly clean all parts.
^ Inspect all parts for damage and wear.

CAUTION: Do not disassemble the Trac-Lok(R) differential assembly or the Truetrac(R) differential assembly. Discard the entire assembly if worn/damaged.

Clean the inside of the differential case before assembly. For Truetrac(R) differentials, submerge the entire differential assembly in a suitable solvent to wash away contaminates from within the housing.
^ Thoroughly clean the differential housing if gears have scores/chips in them.

Installation
1. Carry out the Differential Case End Play Check in the General Procedures portion of this section.

2. Position the special tools and the inner and outer pinion bearing cups in their respective differential housing bores.
1. After placing the inner and outer pinion bearing cups in their bores, place the special tool (inner) on the inner pinion bearing cup.
2. Place the special tool (outer) on the outer pinion bearing cup.
3. Install the special tool.

3. Tighten the special tool to seat the pinion bearing cups into their bores.

4. CAUTION: Always install new pinion bearings when installing new bearing cups.

Note: If the feeler gauge can fit between a cup and the bottom of its bore at any point around the cup, remove and reseat the cup.

Check that the cups have seated correctly in their bores.

5. CAUTION: If any of the gauge surfaces have nicks in them, remove the high spots with a medium India oilstone to prevent erroneous readings.

Note: Apply only a light oil film on the pinion bearings before assembling the tools.

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

6. Note: This step simulates pinion bearing preload.

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

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

Rotate the Gauge Block several half-turns to ensure correct seating of the pinion bearings and position the Gauge Block.

8. Install the special tool.
1. Position the special tool.
2. Install the bearing caps.
3. Install the four bolts.

9. Note:
^ Use a feeler gauge or flat, clean drive pinion position shims as a measuring device.
^ 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 flat, clean drive pinion position shims, measure between the Gauge Block and the Gauge Tube. Record the measurement. Refer to Pinion Ring Gear Variation Number for shim selection information.
^ Remove the special tools after making the correct shim selection.

10. CAUTION: Follow the drive pinion bearing preload shim and drive pinion position shim assembly sequence as directed or unit failure can result.

Install the correct thickness drive pinion position shim, and the oil slinger, if so equipped, on the pinion.

11. Note: Always use the same new inner pinion bearing installed when taking the measurement for drive pinion position shim selection.

Using the special tool, an axle bearing/seal plate, and a suitable press, install the pinion bearing.

12. Note: Use the thickness of the old drive pinion bearing preload shims as a starting point for setting pinion bearing preload.

Inspect the drive pinion bearing preload shims for damage. Discard them if necessary. New shims are available in the thickness shown in the following chart.
13. Assemble the drive pinion bearing preload shims onto the pinion and install the pinion into the differential housing.
14. Install the outer pinion bearing.

15. Using the special tool, install the pinion flange.

16. Install the old washer and the lock nut.

17. Using a Nm (inch-pound) torque wrench, rotate the pinion. The torque must read as specified.
^ To increase the preload, remove drive pinion bearing preload shims. To decrease the preload, add shims.

18. If the pinion bearing preload is within specification, and the pinion position shim has changed, change the drive pinion bearing preload shims by the same amount.
^ The direction arrow pointing toward the pinion flange indicates that by removing the drive pinion position shim, the distance from the centerline of the tubes to the pinion backface increases, giving a plus (+) reading. The drive pinion bearing preload shim pack does not affect the pinion depth setting. However, if the pinion position is changed, the pinion preload will change and may require adjustment to bring the torque-to-rotate within specification. Arrows on the ring gear illustrate the method to increase or decrease backlash and differential bearing preload.

19. With the drive pinion at the correct preload as determined earlier in this procedure, remove and discard the lock nut and the washer.

20. Using the special tool, remove the pinion flange.
21. Coat the pinion seal rubber lips with lubricant.
^ Use SAE 75W-140 High Performance Rear Axle Lubricant F1TZ-19580-B or equivalent meeting Ford specification WSL-M2C192-A.

22. Using the special tool, install the pinion seal.
^ After installation, verify that the garter spring did not pop out of the seal. If the garter spring popped out, install a new pinion seal.
23. Coat the inside of the pinion flange with a small amount of lubricant.
^ Use SAE75W-140 High Performance Rear Axle Lubricant F1TZ-19580-B or equivalent meeting Ford specification WSL-M2C 192-A.

24. Using the special tool, install the pinion flange.

25. CAUTION: Always install a new washer and lock nut.

Install the new washer and lock nut.
26. Carry out the Ring Gear and Pinion Backlash procedure in the General Procedures portion of this section.
27. Assemble the differential bearing cups to the differential bearings.

28. CAUTION:
^ Do not spread the differential housing more than specified.
^ Avoid nicking the ring gear teeth and the anti-lock speed sensor ring during assembly.

Using the special tools, spread the differential housing to the specification.
^ Use a rawhide hammer to seat the differential into the differential housing pocket.
^ Remove the special tools.

29. CAUTION: Match the mating letters as noted during disassembly.

Install the bearing caps, aligning the letters with those on the differential housing. Tighten the bolts to specification.

30. Using the special tools, measure the differential ring gear and pinion backlash at three equally spaced points.
^ The backlash tolerance is 0.13 - 0.203 mm (0.005 - 0.008 inch) and cannot vary more than 0.05 mm (0.002 inch) between points checked. A backlash variation of more than 0.05 mm (0.002 inch) indicates gear/case runout.
^ Move the differential ring gear toward the pinion to correct high backlash.
^ Move the differential ring gear away from the pinion to correct low backlash.
^ Moving a specified amount of differential bearing shims from one side of the differential to the other makes these corrections.

31. Confirm the total preload.
^ Using a Nm (inch-pound) torque wrench, check the torque to rotate the pinion. The reading must be higher than the initial reading (taken without the differential case installed) by the amount shown, with new bearings installed as recommended.
^ If the total preload is too high, remove an equal amount of differential bearing shims from each differential case hub. If the total preload is too low, add an equal amount of differential bearing shims to each differential case hub.
32. Carry out the Tooth Contact Pattern Check to verify the final pinion position is correct.
33. Install the axle shafts.

34. CAUTION:
^ Clean both flat surfaces (differential housing and differential housing cover) with a suitable solvent to remove all traces of oil film.
^ Install the differential housing cover within 15 minutes of applying the silicone, or it will be necessary to remove and reapply new sealant.

Note: The differential housing cover requires a silicone rubber sealer material, such as Clear Silicone Rubber F7AZ-19554-CA or equivalent meeting Ford specification ESB-M4G92-A, rather than a gasket.

Apply a continuous bead of sealant of the specified thickness to the differential housing cover.
^ Use Clear Silicone Rubber F7AZ-19554-CA or equivalent meeting Ford specification ESB-M4G92-A.
35. Place two bolts into the differential housing cover at the 8 o'clock and 2 o'clock positions. Install the differential housing cover.
^ Use the two bolts to position the differential housing cover on the differential housing.

36. Install the remaining bolts. Tighten the bolts alternately and evenly.
^ Allow 1-hour cure time before filling the axle with the correct amount of specified lubricant.

37. Note: Align the index marks made during removal.

Connect the driveshaft to the rear axle.

38. CAUTION: For Trac-Lok(R) axles, first rill the axle with 0.2365 liters (0.5 pints) of Additive Friction Modifier C8AZ-19B546-A or equivalent meeting Ford specification EST-M2C118-A.

Fill the axle with the specified type and amount of lubricant.