Usage:
1. Install pinion (3) in housing (4) complete with the bearings.
2. Install washer (5) and nut (6). Do not install seal (11).
3. While pinion (3) is slowly turned, tighten nut (6) to obtain a rolling torque of ... 1.12 to 3.15 N·m (10 to 28 lb inch).
4. If the rolling torque exceeds the specification, back off 1/8of a turn, reseat the bearings and recheck. Check the assembly for zero end play.
NOTE: Reduce preload torque ... 0.6 N·m (5.31 lb inch)for used bearings with more than 100 hours of operation.
Illustration A
5. When the torque for rotating the pinion is correct, stake nut (6) by peening the collar into the slot in the pinion shaft. Proper peening requires the use of a spherical nose punch with a diameter of (B). Hold the punch at an angle that equals (A). The desired result is a stake of minimum length (C) and minimum depth (D). See Illustration A for a view of a completed staked nut.
List of dimensions for a staked nut.
- Dimension (A) ... 10 to 30°Dimension (B) ... 7.5 to 8.0 mm (.30 to .32 inch)Dimension (C) ... 4.7 mm (.19 inch)Dimension (D) ... 2.5 mm (.10 inch)
NOTE: The nut may be reused if the collar is not cracked during removal or during restaking.
6. Install the pinion subassembly in carrier assembly (9) with 80 percent of shim pack (2) and with the bevel gear group. Make sure that the axle centerline is vertical and that the teeth of bevel gear (7) are facing upward, as shown.
7. Tighten one of two bolts (10) in each bearing cap to a torque of ... 70 N·m (50 lb ft). Tighten the other bolt in each bearing cap to a torque of ... 5 N·m (4 lb ft).
8. Move adjusting nuts (1) and (8) to a position that maintains the gear backlash and a slight bearing end play, but not a tight gear mesh.
9. Measure the torque required to rotate pinion (3) and record the measured torque.
10. Move adjusting nut (8) while rotating bevel gear (7) to zero backlash position. Move adjusting nut (8) back to the nearest lock position.
11. Move adjusting nut (1) until the torque to rotate pinion (3) is increased ... 0.6 to 1.1 N·m (5.3 to 9.7 lb inch)more than the torque found in Step 9. This is the seated position.
12. Tighten adjusting nut (1) by three lugs to the nearest lock position.
13. Measure the backlash between bevel gear (7) and pinion (3). The backlash must be ... 0.36 ± 0.13 mm (.014 ± .005 inch).
14. If the backlash does not meet the specification, retract one nut the same amount the opposite nut is advanced to keep the bearing preload.
15. Tighten two ... 30 mmbearing cap bolts (10) to ... 1800 ± 200 N·m (1325 ± 150 lb ft)and two ... 24 mmbearing cap bolts (10) to ... 900 ± 100 N·m (660 ± 75 lb ft)
16. Measure overall rolling torque at pinion (3). Rolling torque should be ... 3.1 to 11.4 N·m (27.44 to 100.90 lb inch).
NOTE: The differential preload will be kept only if one adjustment ring is loosened and the other adjustment ring is tightened the same amount.
Illustration B
17. After the backlash and preload adjustments have been made, the tooth contact between pinion (3) and bevel gear (7) must then be checked. Perform the procedure that follows:
a. Put a small amount of Prussian blue, red lead or paint on three or four adjacent teeth of bevel gear (7).
b. Rotate pinion (3) several resolutions in one direction and then several resolutions in the opposite direction. Then turn pinion shaft in one direction until the marked teeth on the bevel gear can be seen.
c. The correct area of tooth contact starts near the inside end of the teeth of bevel gear (7) and goes a maximum of 50 percent of the length of the teeth. See Illustration B for an example of the correct area of tooth contact.
Illustration C
18. If the markings made on the teeth of bevel gear (7) looks like the marks in Illustration C, perform the procedure that follows:
a. Add some of shims (2) to move the pinion away from the bevel gear.
b. Perform Steps 9 through 16 again.
c. Perform Step 17 again to check the area of tooth contact.
Illustration D
19. If the marking made on the teeth of bevel gear (7) look like the marks in Illustration D, perform the procedure that follows:
a. Remove some of shims (2) to move the pinion toward the ring gear.
b. Perform Steps 9 through 16 again.
c. Perform Step 17 again to check the area of tooth contact.
NOTE: Always make sure that the backlash adjustment is correct before an adjustment is made to the area of tooth contact. Several adjustments to the backlash and tooth contact may be necessary to correctly adjust the differential and bevel gear group. Always remember that a change to gear clearance (backlash) will also change the gear contact. A change in gear contact will also change gear clearance (backlash).
20. After adjustments are made, remove the Prussian blue, red lead or paint from the gears.
21. Install the retainer and seal (11).
NOTE: Coat the seal bore with 6V-6640Gasket Maker before installing seal (11).