INFO. ON ELECT. SHIFT TRANSFER CASE REPAIR PROCEDURE

SUBJECT: T-CASE GRINDS WHEN SHIFTING FROM 4LOW TO 4HIGH, WON'T SHIFT OUT OF 4- LOW (INSTALL SERVICE KIT)

VEHICLES AFFECTED: 1992-93 T-TRUCKS W/RPO NP1

THIS BULLETIN IS BEING REVISED TO INCLUDE THE REPAIR PROCEDURE.

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

MODELS: ------ 1992-1993 T-TRUCKS EQUIPPED WITH ELECTRIC SHIFT TRANSFER CASE (RPO NP1)

CONDITION:

--------- Some 1992-1993 T-Trucks equipped with electric shift transfer Gases (RPO NP1) may experience the following conditions:

1. Grinds when shifting from 4-Low to 4-High. 2. Will not shift out of 4-Low.

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 to correct these conditions is now available. The parts have been revised to allow for proper shift engagement.

SERVICE PROCEDURE

Please refer to Section 7D TRANSFER CASE in the X-9337 1993 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

WARRANTY INFORMATION

For vehicles repaired under warranty use:

Labour Operation Labour Time ---------------- ----------- K4400 See applicable for Skid Plate, ADD: Labour Time Guide

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.