Usage:
NOTE: The information supplied in this service letter may not be valid after the termination date of this program. Do not perform the work outlined in this Service Letter after the termination date without first contacting your Caterpillar product analyst.
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 "PS0496" as Part Number, "7755" as Group Number, and "96" as Description Code.
Termination Date
September 30, 1992Problem
The midrollers bearings may fail on certain Challenger 65 Tractors. The midrollers can be rebuilt to extend their service live.
Affected Product
Model & Identification Number
Challenger 65 (7YC1-1784)
Parts Needed
- 8H2265 Ring
- 3W5775 Axle
- 3W5776 Retainer
- 3W5777 Hub Assembly
- 3W5779 Bearing
- 3W5781 Plate
- 9W7220 Seal Group
- 6V6640 Sealant
- 3W5775 Axle
Use as required
Action Required
Follow the procedures in the Service Manual to install the new parts. Refer to the procedure and instructions in Special Instruction SEHS9285 "Use of 4C8701 Axle Installation Fixture Group" to replace the existing 3W5775 Axles in the axle assemblies.
The following information should be observed for inspection and rebuild of individual rollers.
1. All bearings that are loose in their bores must be replaced.
2. All hubs in which bearings have turned should have the bores measured where the bearings have turned. The maximum use again bore size for the bearing retaining land is 54.021 mm (2.127").
3. The clearance between shafts and bearings has recently been increased. The nominal shaft to bearing clearance has been increased to 0.25 mm (0.010").
NOTE: Hub assemblies and bearings that are currently in parts inventories will not have this change.
4. If new hub assemblies are being used, the new bearings should be removed from the hubs for honing. New bearings from parts stock should also be honed before installation.
Hone the inside diameter to 47.93 mm ± 0.025 mm (1.887 ± 0.001"). Honing can be started with 200 grit but must be finished with 400 or finer gift. Dealers can use brake hones in " or " air drills running at relatively slow speed. The bearings can be hand held.
5. Used bearings must be removed from their hubs and honed to 47.88 ± 0.025 mm (1.885 ± 0.001"). Many used bearings with scored or scratched bores can be salvaged for reuse by this method.
6. Hubs must be thoroughly cleaned before assembly. Use 7M7456 or 4C4032 Bearing Mount to secure the bearings in the hubs.
7. Fill the hubs with 296 ML (10 oz) of SAE 30 diesel engine oil.
Service Claim Allowances
NOTE: This is a 24-hour job. It is an additional 1.5- hour job to install each new axle.
Parts Disposition
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.