FITTING KIT 9U6781 - Caterpillar

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.
This Program must be administered as soon as possible. When reporting the repair, use "PI3949" as the Part Number, "7751" as the Group Number, "56" as the Warranty Claim Description Code and "T" as the SIMS Description Code. Exception: If the repair is done after failure, use "PI3949" as the Part Number, "7751" as the Group Number, "96" as the Warranty Claim Description Code, and "Z" as the SIMS Description Code.
Completion Date
July 31, 1997Termination Date
January 31, 1998Problem
New 1154877/">115-4877 Sun Gears need to be installed in certain 793 OHT. Insufficient heat treatment of these gears has lead to spalling of the gear teeth.
Affected Product
Model & Identification Number
793 (3SJ1-56)
793B (1HL1-524)
793C (4AR1-79)
Parts Needed
Dealers will need to order parts for this Program.
1 - 1154877 Gear-Sun Qty per final drive. Whenever possible, both final drives must be updated at the same time.
Action Required
Refer to the Service Manual as necessary.
Remove the 7I5594 Cover from the wheel.
Remove the drive axle and the 8X0501 Sun Gear to get access to the first reduction sun gear.
Replace the 1154877/">115-4877 Sun Gear or 8X0468 Sun Gear (first reduction) with a new new 1154877/">115-4877 Gear that has an "F" etched on the side of the gear.
The rear wheels (tires) do not need to be removed to make this repair.
Owner Notification
U.S. and Canadian owners will receive the attached Owner Notification.
Service Claim Allowances
This is an 8-hour job for one (1) final drive. Whenever possible, both final drives must be updated at the same time. Spare final drives may be updated seperately, but must be done before they are put into service.
U.S. and Canadian Dealers Only - Eligible dealers may enter a Type 2 SIMS Report.
Parts Disposition
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.
MAKE EVERY EFFORT TO COMPLETE THIS PROGRAM AS SOON AS POSSIBLE.
Attach.(1-Owner Notification)Copy Of Owner Notification For U.S. And Canadian Owners