Service Procedure

SERVICE PROCEDURE

1. Remove torsional damper and front cover per the 1993 Service Manual. section 6A5 using tool J39046.

NOTICE:
Extreme care should be used when removing front cover from engine block to prevent damage to oil pan gasket. Oil pan gasket is attached to front cover at RTV joints.

2. Remove crankshaft sprocket using tool J28509-A. See section 6A5 in the Service Manual.





3. Inspect crankshaft sprocket for excessive wear. Place new crankshaft sprocket and crankshaft sprocket removed from truck on a flat surface on edge (see illustration # 1). If old gear is 1/8 (0.125) inch smaller. go to step # 4. If old gear is the same or less than 1/8 (0.125) inch smaller, go to step # 5.
4. Install new crankshaft sprocket using tool J22102, camshaft sprocket and timing chain, and magnetic oil drain plug.
5. Only install new crankshaft sprocket using tool J22102.
6. Install front cover and torque bolts to 10 Nm (96 lbs. in.). Install torsional damper and torque bolt to 115 Nm (85 lbs. ft.).
7. Change oil and filter.
8. Only return the crankshaft sprocket to:

G.M. Powertrain
30003 Van Dyke
Warren, MI 48090
Room 2-207

NOTICE:
All crankshaft sprockets are to be wire tagged with complete VIN #, mileage, and date.

9. Install "Campaign Identification Label".


PARTS INFORMATION





Parts are to be obtained from General Motors Service Parts Operation (GMSPO). To ensure that these parts will be obtained as soon as possible, they should be ordered from GMSPO on a C.I.O. order with no special instruction code but order under an advise code (2).

NOTICE:
Due to the limited number of involved vehicles. parts should be ordered based on involved vehicle listings.

WARRANTY INFORMATION





Dealers should submit a warranty claim on each vehicle completed under this campaign.

NOTE:
CONTACT YOUR GMC DISTRICT SERVICE MANAGER IF YOU HAVE ANY ADDITIONAL QUESTIONS.

CAMPAIGN IDENTIFICATION LABEL

Each vehicle corrected in accordance with the instructions outlined in this Product Campaign Bulletin will require a "Campaign Identification Label." Each label provides a space to include the campaign number and five (5) digit dealer code of the dealer performing the campaign service. This information may be inserted with a typewriter or ball point pen.

Each "Campaign Identification Label" is to be located on the radiator core support in an area which will be visible when the vehicle is brought in for periodic servicing by the owner.

Apply "Campaign Identification Label" only on a clean, dry surface.

ADMINISTRATIVE PROCEDURE

Procedures covering this campaign are outlined in Section V of your dealership's "GMC Truck Warranty Claims Processing Manual" # P9119.