CABLE 4C9801 - Caterpillar

Caterpillar: Confidential Yellow
PRIORITY - NEW SHAFT NEEDS TO BE INSTALLED IN INTERAXLE DIFFERENTIAL TO PREVENT PINION BEARING AND THRUST WASHER FAI LURES ON CERTAIN D400 AND D35C-HP ARTICULATED DUMP TRUCKS - MAILED US, COFA, CANADA, COSA - SERVICE LETTER SUPPLEMENT
  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.
SERVICE LETTER SUPPLEMENT U-29 AU-9 O-8 Some information needs to be added to the following Service Letter. December 17, 1986 - PI3205; New Shaft Needs To Be Installed In Interaxle Differential To Prevent Pinion Bearing And Thrust Washer Failures On Certain D400 And D35 HP Articulated Dump Trucks Under the heading Affected Product add the following This Program should not be administered, if the Affected Product is equipped with a no-spin differential in the trailer axle. The following procedure describes how to determine if the trailer is equipped with a no-spin differential. This procedure should be attached to the existing Rework Procedure. Test For No-Spin Differential 1. Park the truck on level ground and block the front wheels to prevent movement of the truck. 2. D35 HP - Block the truck so that both rear wheels are off the ground. D400 - Block the truck so that wheels on center or rear axle are off the ground. Perform the following steps and then check the other axle. 3. D35 HP - Apply the parking brake. D400 - Disengage the parking brake. 4. With another person on the other side, rotate both wheels forward as far as possible. Normally both wheels will stop after rotating only a short distance. 5. With one person holding the right hand wheel fully forward against the stop, rotate the left hand wheel backward and listen for a regular indexing or clicking sound. The right hand wheel must be held firmly against the stop or the left hand wheel will not disengage freely. 6. If clicking noise can be heard, the truck has a no-spin differential. If one wheel rotates forward and the other backwards, the truck has a standard differential.