M/T - 5TH Gear Whine
Number: 93-172-7BSection: 7B
Date: MAY 1993
Corporate Bulletin No.: 367201
ASE No.: A3
Subject:
5TH GEAR WHINE
Model and Year:
1989-93 "S" TRUCKS EQUIPPED WITH 2.8L OR 2.5L ENGINES AND MANUAL TRANSMISSION
Some owners of 1989-1993 2WD S-Trucks equipped with 2.8L or 2.5L engines (RPO LL2 or L38/LN8) and manual transmissions may comment about a whine or a gear noise when the transmission is in the 5th gear position. The noise usually occurs at highway speeds.
CAUSE:
The audible noise is a result of the internal gearbox working noises being transferred and amplified through the shift lever.
CORRECTION:
To isolate the audible noise from being transferred into the interior of the truck, a revised shift lever has been released.
SERVICE INFORMATION:
(Refer to Figure 1)
1. Remove the shift knob (5) and lock nut (6).
2. Remove the shift lever (7) and the lock nut (11).
Hold the lock nut and unscrew the shift lever using the wrench slots (A).
3. Cut off the top, non-threaded, portion of the shifter stub shaft at the end of the threads (Figure 2).
IMPORTANT:
DO NOT LEAVE MORE THAN 10 MM MATERIAL ABOVE THE TOP THREAD.
4. Install the lock nut (11), do not tighten.
5. Install the revised shift lever (P/N 15965641) and tighten the lock nut (11) up against the shift lever to 47 N-m (35 lbs.ft.).
6. Install the lock nut (6) all the way on, do not tighten.
7. Screw the shift knob against the lock nut, back the shift knob off to align the shift pattern and tighten the lock nut against the knob.
SERVICE PARTS INFORMATION:
PART NO. DESCRIPTION
15965641 Shift lever
Parts are currently available from GMSPO.
WARRANTY INFORMATION:
For vehicles repaired under warranty, use:
Labor Operation: K1060
Use applicable labor time guide for labor hours.