Product Support Program For Installing Tapered Roller Bearing Midroller Hubs On Certain Challenger 65 Tractors Caterpillar

Product Support Program For Installing Tapered Roller Bearing Midroller Hubs On Certain Challenger 65 Tractors

Usage:

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Caterpillar: Confidential Yellow

NOTE: This Program can only be administered after a failure occurs. The decision whether to apply the Program is made by the dealer. When reporting the repair, use "PS0487" as Part Number, "7755" as Group Number, and "96" as Description Code.

NOTE: This Revised Service Letter replaces the March 28, 1991 Service Letter and the June 14, 1991 Service Letter Supplement. A change was made to the Termination Date.

Termination Date

June 30, 1994

Problem

The midrollers may fail on certain Challenger 65 Tractors. The mid rollers and their supports can be rebuilt using tapered roller bearings.

Affected Product
Model & Identification Number

Challenger 65 (7YC1-1784)

Parts Needed

16 - 8B7614 Nut

4C8701 Tool Group (Maximum of one per branch)

16 - 1J9671 Seal

16 - 1M8747 Seal Group

16 - 1N5970 Locknut

16 - 5P9651 Cone

8 - 8R8780 Axle

16 - 8R9006 Retainer

16 - 8R9021 Hub Assembly

16 - 6S6032 Cone

16 - 9S8003 Plug

4 - 6V6640 Sealant

16 - 541303 Washer

Action Required

1. Deflate the air springs, remove the inner midwheels from the hubs, remove the minor bogies from the major bogies, and remove the minor bogies from the tractor.

2. Disassemble the minor bogies to the 5G8250 Axle Assembly (Earlier) or 8R6668 Axle Assembly (Later).

3. Set the following parts aside. They will be reused during assembly.

2A0762 Bolts

5G8250 or or 8R6668 Axle Assembly

5P0537 Washers

1R0641 Roller Assembly

3W5782 Covers

4. Follow the procedure in Special Instruction SEHS9285 "Use of 4C8701 Axle Installation Fixture Group". Replace the 3W5775 Axles in the axle assemblies with 8R8780 Axles.

5. Install the roller bearing hubs on the axle assemblies. Adjust the bearings as follows:

A) Make sure the outboard bearing cone is loose on the axle (slides easily) and that the locknut rotates freely on the axle threads.

Option #1

While rotating or oscillating hub, tighten the locknut to 34 ± 7 N·m (25 lb ft). Use a 4C9439 Wrench-Spanner.

or Option #2

a) Tighten the locknut to 34 ± 7 N·m (25 lb ft).

b) Rotate or oscillate the hub an equivalent of 3 revolutions.

c) Tighten the locknut to 34 ± 7 N·m (25 lb ft).

d) Repeat Step b) and Step c).

C) If any locknut slot and washer tang are aligned, bend the aligned tang into the slot to lock in place. If none of the washer tangs and locknut slots are aligned, tighten the locknut until the most nearly aligned tang and slot line up. Bend the washer tang into the locknut slot to lock in place.

6. Clean the end of the hubs and the mating faces of the 3W5782 Covers. Install the covers using 6V6640 Sealant. Fill each hub with 260 ml (8.8 oz) of SAE 30 drive train oil.

7. Install the axle assembly on the tractor. Install the roller assemblies. Lubricate the major and minor bogie fittings. Inflate the air springs.