SERVICING CAM AND/OR CRANK GEARS (REPLACE GEAR SET)

MODELS: 1985-89 S/T TRUCKS AND M VANS W/2.5L (VIN CODE E) ENGINE

THIS BULLETIN CANCELS AND REPLACES GMC TRUCK SERVICE BULLETIN 89-T-68, DATED JUNE, 1989 TO DELETE THE INSTALLATION OF THE TORSIONAL DAMPER. ALL COPIES OF 89-T-68 SHOULD BE DISCARDED.

When servicing the camshaft and/or crankshaft gears on 2.5L engines, it is recommended that a new gear set kit be used to replace the individual gears. The gear kit is comprised of a set of camshaft and crankshaft gears for improved wear resistance.

IMPORTANT: The camshaft/crankshaft gear kit should be installed any time the camshaft or crankshaft gears need to be replaced.

The kit part number is as follows:

VIN Gear Kit Applicable Engine Code Part Number Model Years ------------ ----------- ------------ E 10101790 1985-1989

GMSPO has superseded the individual camshaft gear part numbers with the gear kit part numbers.

Parts are currently available from GMSPO.

Refer to "Service Manual Update" dated Septem- ber 1988 (Section 6A1) for camshaft/crankshaft gear replacement procedures.

For vehicles repaired under warranty, use:

Labor Operation: J0840 Labor Time: M-Van 2.3 Hours (plus applicable "adds") S/T 2.7 Hours (plus applicable "adds")

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.