INFO. ON ELECT. SHIFT TRANSFER CASE REPAIR PROCEDURE. GMC Truck S15 Pickup - 4WD 1992

For 1990-2009 cars

# INFO. ON ELECT. SHIFT TRANSFER CASE REPAIR PROCEDURE

REVISION 05/21/93

THIS BULLETIN IS BEING REVISED TO INCLUDE THE REPAIR PROCEDURE.

REVISION: 03/08/94

THIS BULLETIN IS BEING REVISED TO INCLUDE THE SHIFT SECTOR PART NUMBER AND ADD ANOTHER CONDITION. PREVIOUS DIVISIONAL PUBLICATION NUMBERS WERE:

--------------------------------------------------------------------- DIV BULLETIN # PUBLISH DATE CHEVROLET 93-225-7D 6/17/93 GMC TRUCK 93-7D-88 6/08/93 GM CANADA 93-7D-102 9/27/93 ----------------------------------------------------------------------

#### SUBJECT: ELECTRIC SHIFT TRANSFER CASE (NP233E) DOES NOT SHIFT OUT OF 4-LOW, GRINDS WHEN SHIFTING FROM 4-LOW TO 4-HIGH, OR SLIPS OUT OF 4-HIGH (REVISED RANGE SHIFT FORK, HUB KIT, AND SHIFT SECTOR RELEASED)

#### MODELS: 1992-93 CHEVROLET AND GMC TRUCK T TRUCKS EQUIPPED WITH ELECTRIC SHIFT TRANSFER CASE (RPO NP1)

#### CONDITION:

SOME OWNERS MAY EXPERIENCE THE FOLLOWING CONDITIONS:

1. GRINDS WHEN SHIFTING FROM 4-LOW TO 4-HIGH. 2. WILL NOT SHIFT OUT OF 4-LOW. 3. SLIPS OUT OF 4-HIGH (USUALLY RESULTS IN RATCHET NOISE).

#### CAUSE:

THESE CONDITIONS MAY BE DUE TO THE RANGE SHIFT FORK AND RANGE SHIFT HUB PREVENTING PROPER SHIFT ENGAGEMENT OF THE PLANETARY CARRIER AND THE INPUT GEAR.

#### CORRECTION:

A REVISED RANGE SHIFT FORK ASSEMBLY (INCLUDING PADS), INPUT GEAR, AND RANGE SHIFT HUB SERVICE KIT (TRANSFER CASE FIELD SERVICE KIT, P/N 15971058) TO CORRECT THESE CONDITIONS ARE NOW AVAILABLE. THE PARTS HAVE BEEN REVISED TO ALLOW FOR PROPER SHIFT ENGAGEMENT. IN ADDITION, A REVISED SHIFT SECTOR (P/N 12544302) SHOULD BE INSTALLED IN CONJUNCTION WITH THE TRANSFER CASE FIELD SERVICE KIT.

#### SERVICE PROCEDURE:

PLEASE REFER TO SECTION 7D TRANSFER CASE IN THE APPROPRIATE LIGHT DUTY TRUCK UNIT REPAIR MANUAL (DISASSEMBLY AND ASSEMBLY OF INTERNAL COMPONENTS).

SERVICE PARTS INFORMATION:

PART NUMBER DESCRIPTION QUANTITY 15971058 KIT-TRANSFER CASE FIELD SERVICE 1 12544302 SHIFT SECTOR 1

PARTS ARE EXPECTED TO BE AVAILABLE FROM GMSPO ON 3/7/94.

#### WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY USE:

LABOR OPERATION LABOR TIME ------------------- ---------------- K4400 SEE APPLICABLE LABOR TIME GUIDE

FIGURES: 0

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.

COPYRIGHT 1994 GMC TRUCK DIVISION, GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.