CONFIDENTIAL TIBU3856-01

The contact stress between the bearing and the stopper in the final drive may cause the stopper to deform, reduce the preload of the bearings, allow the stopper to rotate, and damage the internal components of the final drive.

Improvements to the components in the final drive eliminate the loss of bearing preload. A hardened stopper eliminates the stopper deformation. New dowels positively secure the stopper and eliminate the rotation of the stopper. Illustration 1 shows a final drive with the improvements installed. Use the components that are listed in Table 2 and Table 3 in order to enhance the bearing preload system. System stiffness is optimized by an increase in stopper thickness and hardness.

The affected machines are listed in Table 1. The repair process that follows is applicable to the North American Commercial Division (NACD) and the Latin American Commercial Division (LACD) marketing organizations only.

Table 1. Affected Machines

In order to establish bearing preload, torque the 227-6100 Stopper to 1355 N?m (1000 lb ft). Do not use the measurement method for the establishment of the bearing preload.

Table 2. Various Components Affected

Table 3. Improved Components In The Final Drive

Torque the 227-6100 Stopper to 1355 N?m (1000 lb ft). Use a 235-4848 Drill Fixture Group in order to drill and ream the two dowel holes in the 199-4748 Motor Housing and the 227-6100 Stopper. Locate the dowel holes to the dimensions that are shown in Illustration 4. Orient the two dowel holes 180 degrees apart. Position shop towels between the motor housing and the sprocket housing. Connect a vacuum to the 235-4848 Drill Fixture Group in order to prevent contamination and metal chips from entering the drive during the machining process.

Illustration 1. Final Drive Assembly
(A) Motor housing
(B) Dowel
(C) Sprocket housing
(D) Plate
(E) Bolt

Illustration 2. Components In The Final Drive Assembly
(A) 199-4748 Motor Housing
(B) 227-6102 Dowel
(C) 199-4850 Sprocket Housing
(D) 227-6101 Washer Plate
(E) 8T-0293 Bolt
(F) 227-6100 Stopper
(G) 196-4873 Ball Bearing

Note: Apply sealant to the threads of bolt (E) and torque to
100 ⁺/_- 20 N?m (75 ⁺/_- 15 lb ft).

Illustration 3. Section View Of Final Drive

Illustration 4. View H-H From Illustration 3.
(A) Motor housing
(F) Stopper
(J) 285.0 mm (11.25 inch) diameter
(K) 13.054 ⁺/_- 0.02 mm (0.514 ⁺/_- 0.001 inch) diameter,
14.0 ⁺/_- 0.2 mm (0.55 ⁺/_- 0.001 inch) deep

Illustration 5. Drill Fixture
(L) 235-4848 Drill Fixture Group

Illustration 6. Fixture With The Drill And A Vacuum Line

Illustration 7. 199-4750 Planet Carrier
(M) Planet Carrier
(N) 41.5 mm (1.63 inch)

Dimension (N) in Illustration 7 is 43.5 mm (1.71 inch) for the 191-2523 Planet Carrier. Machine 2 mm (0.08 inch) from the 191-2523 Planet Carrier for the Group 1 machines that are listed in Table 1. The machining is required in order to provide adequate clearance for the increased thickness of the improved stopper.

Do not machine the 199-4750 Planet Carrier for the Group 2 machines that are listed in Table 1.

Illustration 8. Height Of The 15-degree Duo Cone Seal Assembly
(P) 11.5 ⁺/_- 1.0 mm (0.45 ⁺/_- 0.04 inch)

Install duo cone seals with the appropriate installation tooling in order to ensure the correct position and function of the seal.

Note: The maximum inclination per seal ring is 1.0 mm (0.04 inch). The 213-4737 Duo Cone Seal Group has a 15-degree seal. The 15-degree assembly tool is the 8T-9206 Duo Cone Seal Installer Assembly.

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