COVER 9L6938 - Caterpillar

Caterpillar: Confidential Yellow
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 can be administered either before or after a failure. In either case the decision whether to apply the Program is made by the dealer. When reporting the repair, use "PS8488" as the Part Number and "7755" as the Group Number. If administered before failure, use "56" as the Warranty Claim Description Code and use "T" as the SIMS Description Code. If administered after failure, use "96" as the Warranty Claim Description Code and use "Z" as the SIMS Description Code.
Mail codes A-195 and TT-22 are not in order since they were added at Revision SEBE5530-01 in December 1995.
This Revised Service Letter replaces the October 10, 1995 Service Letter. Changes have been made to the Mail Codes.
Termination Date
October 31, 1996Problem
The speed/timing sensor may fail due to the sensor slip head impacting on the camshaft gear on certain 3406E Truck Engines.
Affected Product
Model & Identification Number
3406E (5EK45702-46452, 5EK53004-53939 )
Parts Needed
1 - 1268481 WasherAction Required
1. Remove the sensor. (Inspect for damage to the slip head and if replacement is necessary replace with a new 1271008 Sensor Assembly).2. Extend the slip head.3. Install the sensor and tighten to a torque of 40 5 N m (30 4 lb ft). Ensure that the Timing Wheel is in a position that will not allow the slip head of the Speed/Timing Sensor to fill one of the slots of the Timing Wheel before the Sensor is installed (visually inspect with a flashlight). Turn the crankshaft to rotate the Timing Wheel if necessary to position the wheel in a place that will not allow the slip head to fill a slot. If the sensor slip head does fill one of the slots, then the slip head will be broken off as the wheel begins to rotate.
4. Remove sensor but do not touch the slip head.5. Install the 0.020" 1268481 Washer to the slip head end of the sensor.6. Install the sensor and tighten to a torque of 40 5 N m (30 4 lb ft).7. Perform the timing calibration procedure. (Refer to the Electronic Troubleshooting Manual SENR5582-02, page 189).Service Claim Allowances
This is a 1-hour job.
Parts Disposition
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.