COMPRESSOR GP -B 10R9391 - Caterpillar

Caterpillar: Confidential Yellow
SUPPORT DIRECT DRIVE TRANSMISSION FAILURE ON D5B SA TRACTOR PS0256 DISTRIBUTION TO US, CANADA, AMERICAS, AUSTRALIA
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DIRECT DRIVE TRANSMISSION FAILURE ON D5B SA TRACTOR, 3060, 3061, PS0256 U-52 A-28 AU-40 C-41 support
Problem
Some D5B Special Application Tractors with direct drive transmissions have early hour transmission failures. One common failure mode is gear tooth chipping, which leads to tooth failure. On the 6-speed transmissions, tooth chipping usually involves the 8S2134 Forward/Reverse Sliding Gear, the 8S2131 Fourth Speed Gear, and/or the 8S2133 Third to Fourth Speed Pinion (Gear). The result of the failure is 1) the transmission locks in gear because a piece of a broken tooth wedges between the gears, or 2) the transmission will not engage a gear because teeth are missing. Other modes of failure which may occur, either with or without the gear teeth failure, are: 1. Failure of the 3S7155 Front Pinion Bearing Cage. 2. Failure of the 4H6195 Lockring. 3. Failure of the 7M1154 Countershaft Bearings. The bearing cage problem is caused by breakage of the bearing retaining lip. The lockrings snap and let the 8S2138 Reverse Pinion (Gear) slide on its shaft. There are not enough countershaft bearing failures to identify a cause at this time. An inadequate flywheel clutch brake is a contributing factor to these failures. The brake is not capable of stopping rotation of the clutch and transmission, under many normal operating conditions, allowing the operator to attempt to mesh the gears before the transmission components have stopped rotating. This results in damage to the gears. At this time, no new parts are available. Repairs must be made using current production parts.
Affected Product
Model Identification Numbers D5B SA 21Y1-Up 26X1-Up
Parts Needed
Use the following parts as required. 1 - 6B9562 Fork 1 - 8S2131 Gear 1 - 6B9567 Fork 1 - 8S2132 Gear 1 - 4H6195 Ring 1 - 8S2133 Pinion 1 - 3S7155 Cage 1 - 8S2134 Gear 1 - 7S6103 Gear A. 1 - 8S2138 Pinion 1 - 8S2129 Gear 1 - 8S2139 Pinion 1 - 8S2130 Gear
Action Required
Repair the failure with parts listed in the current parts book or fiche. Inspect and, if necessary, adjust the flywheel clutch brake to specification. If the transmission does not have the improved 6T6053 Pinion per PS0199, Service Letter dated December 21, 1983, we recommend installing the pinion and 8P1183 Bevel Gear at this time. Claim parts and 50% of the labor allowable under PS0199 (PS0199 extended to May 31, 1986). WARRANTY ALLOWANCES (SEE ILLUSTRATION) This is a 22-hour job without cab and a 24-hour job with cab. Caterpillar participation is for parts at dealer net and