SUBJECT: GEAR RATTLE OR KNOCK IN SECOND GEAR
MODELS: 1982-82 S/T TRUCKS EQUIPPED WITH BORG WARNER 4-SPEED MANUAL
TRANSMISSIONS (RPO M77)
SOME 1982-83 S/T TRUCKS EQUIPPED WITH BORG WARNER 4-SPEED MANUAL
TRANSMISSIONS MAY EXHIBIT A "KNOCK" OR "RATTLE"NOISE WHILE IN 2ND
GEAR AND ACCELERATING. THIS CONDITION MAY BE CAUSED BY THE TRANSMIS-
SION'S REVERSE IDLER TEETH CONTACTING THE MAIN SHAFT REVERSE GEAR
TEETH.
VEHICLES WITH THIS CONDITION CAN BE CORRECTED BY ADDING A TORSION
SPRING, P/N 14079331, TO THE TRANSMISSION'S REVERSE RELAY LEVER
FOLLOWING THE RECOMMENDED PROCEDURE:
1. FOLLOWING INSTRUCTIONS OUTLINED IN GMC SERVICE MANUAL X-8229,
SECTION 7B 1, OR X-8329 S/T TRUCK 77M (4 SPD.) MANUAL TRANSMIS-
SION, REMOVE, DRAIN, AND DISASSEMBLY TRANSMISSION TO EXTENT OF RE-
MOVING CLIP THAT RETAINS REVERSE RELAY LEVER TO REVERSE LEVER
PIVOT PIN.
2. HOLDING REVERSE RELAY LEVER IN POSITION, UNSCREW PIVOT PIN AND
REMOVE FROM CASE.
3. INSTALL TORSION SPRING, P/N 14079331, BETWEEN CASE AND LEVER IN
ORIENTATION SHOWN IN FIGURE 1 WITH SPRING'S LONG TANG POSITIONED
IN FRONT OF WEB OF CASE.
NOTICE: THE VIEW SHOWN IN FIGURE 1 HAS VARIOUS COMPONENTS
(INCLUDING REVERSE RELAY LEVER) REMOVED TO BETTER
ILLUSTRATE HOW THE SPRING IS TO BE MOUNTED AND LOCATED
IN UNIT.
4. APPLY NON-HARDENING SEALER TO THREADS OF PIVOT PIN AND INSTALL PIN
THROUGH CASE, TORSION SPRING, AND REVERSE RELAY LEVER AND TORQUE
TO 35-50 FT. LBS.
5. INSTALL CLIP THAT RETAINS REVERSE RELAY LEVER (AND SPRING) TO
PIVOT PIN AS SHOWN IN FIGURE 2.
6. USING A SUITABLE TOOL OR HOOK FASHIONED SIMILAR TO THE ONE SHOWN
IN FIGURE 3, PULL BENT TANG OF TORSION SPRING BEHIND LEVER AND
HOOK END OF SPRING OVER LEVER AS SHOWN.
7. FOLLOWING INSTRUCTIONS OUTLINED IN GMC SERVICE MANUAL X-8229 OR
X-8329, REASSEMBLE, FILL WITH LUBRICANT, AND INSTALL TRANSMISSION.
IF NECESSARY, ADJUST CLUTCH AS REQUIRED.
THE TORSION SPRING WAS EFFECTIVE IN PRODUCTION TRANSMISSION AT BORG
WARNER WITH THE FOLLOWING MODEL AND SERIAL NUMBERS:
MODEL SERIAL NO. MODEL SERIAL NO.
13-51-000-005 10463 13-53-000-007 10133
13-53-000-001 63503 13-53-000-008 10616
13-53-000-003 22217 (SEE ILLUSTRATION)
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.