Pinion Depth Adjustment 8.6 Inch, 9.5 Inch, 11.5 Inch Axles
Tools Required
• | J 45108 Pinion Setting
Gage Block (9.5 inch axle) |
• | J 21777-86 Side Bearing Disc (2 Required) (9.5 inch axle) |
• | J 34925 Pinion Setting
Gauge Kit (8.6 inch, 9.5 inch axle, 11.5 inch axle) |
• | J 44416 Pinion Setting
Adapter Kit (11.5 inch axle) |
Important: Make sure all of the tools, the differential side bearing bores, and the pinion
bearing cups are clean before proceeding.
- Lubricate the pinion bearings with axle lubricant. Refer to
Fluid and Lubricant Recommendations
in Maintenance and Lubrication.
- Install the pinion bearings into the axle housing.
- Assemble
the following components into the axle housing:
• | For the 8.6 in axle, assemble the J 21777-35 (1),
the J 21777-43 (2), the J 21777-42 (3),
and the J 21777-29 (4) as shown. |
• | For the 9.5 in axle, assemble the J 21777-8 (1),
the J 21777-43 (2), the J 21777-42 (3),
and the J 45108
(4)
as shown. |
• | For the 11.5 in axle, assemble the J 44416-3 (1,4),
the J 21777-43 (2), and the J 44416-2 (3)
as shown. |
- While holding the J 21777-43 stationary, install an inch-pound
torque wrench on the nut of the J 21777-43 and tighten the nut
until a rotating torque of 2.2 N·m (20 lb in)
is obtained.
Rotate the assembly several times in both directions in order to seat the
pinion bearings.
- Check the rotating torque of the assembly. If the torque is less than
1.7 N·m (15 lb in), tighten the nut on the J 21777-43
until a rotating torque of 1.7-2.8 N·m (15-25 lb in)
is obtained.
- Assemble
the following components into the differential carrier bore of the axle housing:
• | For the 8.6 in axle, assemble the J 21777-45 (1, 2)
to the J 21777-1 (3) as shown. |
• | For the 9.5 in axle, assemble the J 21777-86 (1, 2)
to the J 21777-1 (3) as shown. |
• | For the 11.5 in axle, assemble the J 44416-1 (1, 2)
to the J 21777-1 (3) as shown. |
- Install the bearing caps.
Notice: Use the correct fastener in the correct location. Replacement fasteners
must be the correct part number for that application. Fasteners requiring
replacement or fasteners requiring the use of thread locking compound or sealant
are identified in the service procedure. Do not use paints, lubricants, or
corrosion inhibitors on fasteners or fastener joint surfaces unless specified.
These coatings affect fastener torque and joint clamping force and may damage
the fastener. Use the correct tightening sequence and specifications when
installing fasteners in order to avoid damage to parts and systems.
- Install the bearing cap bolts.
Tighten
Tighten the bearing cap bolts to 75 N·m (55 lb ft).
- Rotate the J 21777-1 within the J 21777-45
(8.6 in axle), or the J 21777-86 (9.5 in axle), or the
J 44416-1 (11.5 in axle). The J 21777-1
must rotate back and forth freely within the discs. If the J 21777-1
does not rotate freely, disassemble the components, inspect for proper
seating and/or mis-aligned components and re-assemble.
- Align the plunger of the J 21777-1
(1) to the 8.5 in gauge block setting of the J 21777-29
(8.6 in axle), or the J 45108
(9.5 in axle), or the J 44416-3 (11.5 in
axle) (2).
- Install the J 8001
to
the J 21777-1 as follows:
11.1. | Loosely clamp the J 8001
onto the stem on the J 21777-1. |
11.2. | Place the contact pad of the J 8001
onto the mounting post of the J 21777-1. |
11.3. | With the contact pad of the J 8001
touching the mounting post of the J 21777-1, loosen the
lock nut on the J 8001
and push down on the J 8001
until the needle the J 8001
has
turned 3/4 of a turn clockwise. |
11.4. | Tighten the clamp on the J 8001
finger tight. |
- Move the plunger of the J 21777-1 back and forth until the
needle of the J 8001
indicates
the greatest deflection.
The deflection is the point where the needle changes direction.
- At the greatest point of deflection, move
the housing of the J 8001
until
the needle indicates zero.
- Move the plunger of the J 21777-1 back and forth again to
verify the zero setting. Adjust the housing of the J 8001
as necessary to set the needle to zero.
- Rotate the plunger of the J 21777-1 away from the J 21777-29
(8.6 in axle), the J 45108
(9.5 in axle), or the J 44416-3 (11.5 in axle) until
it no longer touches the J 21777-29 (8.6 in axle), the J 45108
(9.5 in axle), or
the J 44416-3 (11.5 in axle).
- The value indicated on the J 8001
is the thickness of the shim needed in order to set the depth of the
pinion.
- Select the shim that indicates the proper thickness. Measure the shim
with a micrometer in order to verify that the thickness is correct.
- Remove the pinion depth setting tools.
- Remove the pinion bearings.
- Install the pinion shim between the pinion gear and the inner pinion
bearing. Refer to
Drive Pinion Bearings Replacement
.
Pinion Depth Adjustment 10.5 Inch Axle
- Install the differential, if necessary. Refer to
Differential Replacement.
Important: Measure and record the thickness of the pinion gear bearing retainer shim before any service procedures are performed to the pinion gear bearing retainer assembly.
- Install the original shim to the pinion bearing retainer. If the original shim is not available, install a 0.41 mm (0.016 in) shim to build pinion depth.
Important: Do not apply sealant to the pinion gear bearing retainer at this time.
- Install the pinion gear bearing retainer.
Notice: Refer to Fastener Notice in the Preface section.
- Install the pinion gear bearing retainer bolts.
Tighten
Tighten the pinion gear bearing retainer bolts to 88 N·m (65 lb ft).
- Adjust the backlash. Refer to
Backlash Adjustment.
- Perform a gear tooth pattern check on the pinion and the ring gear. Refer to
Gear Tooth Contact Pattern Inspection.
- If the gear tooth contact pattern indicates a high or a low flank contact pattern, adjust the pinion depth by doing the following:
7.1. | Remove the pinion gear bearing retainer bolts. |
7.2. | Remove the pinion gear bearing retainer. |
• | If the gear tooth contact pattern shows a high flank contact pattern, install a shim one size larger. |
• | If the gear tooth contact pattern shows a low flank contact pattern, install a shim one size smaller. |
7.4. | Install the new shim to the pinion gear bearing retainer. |
7.5. | Install pinion gear bearing retainer. |
7.6. | Install pinion gear bearing retainer bolts. |
Tighten
Tighten the pinion gear bearing retainer bolts to 88 N·m (65 lb ft).
7.8. | If the gear tooth pattern is still incorrect, adjust the shim thickness as necessary and recheck the gear tooth pattern of the pinion and the ring gear. |
- Inspect the backlash between the pinion and the ring gear and adjust, if necessary. Refer to
Backlash Adjustment.
The pinion shims are available in the following sizes:
Shim Sizes