M/T - 5TH Gear Whine
BULLETIN NUMBER: 93-7B-64SECTION: 7B
NUMBER: 2
CORPORATE REFERENCE NUMBER: 367201
DATE: April 1993
SUBJECT:
5TH GEAR WHINE (INSTALL REVISED SHIFT LEVER)
MODELS:
1989-93 "S" TRUCKS EQUIPPED WITH 2.8L OR 2.5L ENGINES AND MANUAL TRANSMISSION
CONDITION
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 1).
^ 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 Number Description
15965641 Shift lever
Parts are currently available from GMSPO.
WARRANTY INFORMATION
For vehicles repaired under warranty, use:
Labor Operation: K1060
Labor Time: 0.3 hr