CAMPAIGN: ENG./TRANS. MISMATCH (REBUILD TRANSMISSION)

GENERAL MOTORS HAS BECOME AWARE OF A CONDITION WHERE CERTAIN 1985 AND 1986 MODEL C7D MEDIUM DUTY TOP KICK TRUCKS WERE ASSEMBLED WITH AN IMPROPERLY MATCHED ENGINE/TRANSMISSION COMBINATION. AN ALLISON MODEL MT 643 TRANSMISSION GOVERNED AT 2,600 RPM WAS IMPROPERLY MATED TO A CATERPILLAR MODEL 3208T ENGINE GOVERNED AT 2,200 RPM. THIS MISMATCH RESULTS IN THE TRANSMISSION NOT SHIFTING INTO 4TH GEAR WHEN THE ENGINE IS AT FULL THROTTLE; POOR VEHICLE ACCELERATION CAPABILITY; AND THE TORQUE CONVERTER SLIPPING EXCESSIVELY RESULTING IN HIGHER THAN NORMAL TRANSMISSION OIL TEMPERATURES WHICH WILL SHORTEN TRANSMISSION LIFE. TO PREVENT THE POSSIBILITY OF THIS CONDITION OCCURRING, IT WILL BE NECESSARY TO REBUILD THE TRANSMISSION TORQUE CONVERTER AND VALVE BODY TO SHIFT AT 2,200 RPM ON ALL INVOLVED VEHICLES. VEHICLES INVOLVED INVOLVED ARE CERTAIN 1985 AND 1986 C7 MEDIUM DUTY TOP KICK MODEL TRUCKS EQUIPPED WITH A DETROIT DIESEL ALLISON MT 643 AUTOMATIC TRANSMISSION (RPO ME3) AND A CATERPILLAR 3208T ENGINE (RPO LQC). THE VEHICLES INVOLVED WERE BUILT WITHIN THE FOLLOWING VIN BREAKPOINTS: PLANT MODEL YEAR FROM THROUGH PONTIAC 1985 FV605167 FV631778 PONTIAC 1986 GV502150 GV509713 THE SPECIFIC VEHICLES INVOLVED IN THIS CAMPAIGN HAVE BEEN IDENTIFIED BY VEHICLE IDENTIFICATION NUMBER COMPUTER LISTINGS. THESE LISTINGS ARE FURNISHED TO ALL INVOLVED DEALERS WITH THE CAMPAIGN BULLETIN. DEALER CAMPAIGN RESPONSIBILITY DEALERS ARE TO SERVICE ALL VEHICLES SUBJECT TO THIS CAMPAIGN AT NO CHARGE TO OWNERS, REGARDLESS OF MILEAGE, AGE OF VEHICLE, OR OWNERSHIP, FROM THIS TIME FORWARD. WHENEVER A VEHICLE SUBJECT TO THIS CAMPAIGN IS TAKEN INTO YOUR NEW OR USED VEHICLE INVENTORY, OR IT IS IN YOUR DEALERSHIP FOR SERVICE IN THE FUTURE, YOU SHOULD TAKE THE STEPS NECESSARY TO BE SURE THE CAMPAIGN CORRECTION HAS BEEN MADE BEFORE RESELLING OR RELEASING THE VEHICLE. OWNERS OF VEHICLES RECENTLY SOLD FROM YOUR NEW VEHICLE INVENTORY ARE TO BE CONTACTED BY THE DEALER, AND ARRANGEMENTS MADE TO MAKE THE REQUIRED MODIFICATION ACCORDING TO INSTRUCTIONS CONTAINED IN THIS BULLETIN. IF NO ONWER'S NAME AND ADDRESS WERE AVAILABLE TO GMC TRUCK AT THE TIME OF CAMPAIGN INITIATION, THE DEALER WILL DETERMINE THE OWNER'S NAME AND ADDRESS FROM THE DEALERSHIP SALES RECORDS. PLEASE PROVIDE THIS INFORMATION DIRECTLY ON THE SECOND COPY OF THE LISTING NEXT TO THE APPLICABLE VIN, SO THAT OUR RECORDS MAY BE UPDATED AND THE APPROPRIATE NOTIFICATION MAILED TO THE OWNER. THIS SECOND COPY SHOULD THEN BE SUBMITTED TO THE ADDRESS LISTED BELOW IN THE PREVIOUSLY SUPPLIED YELLOW CAMPAIGN ENVELOPES. GMC TRUCK GENERAL MOTORS CORPORATION 101 UNION STREET PLYMOUTH, MICHIGAN 48170 OWNER NOTIFICATION OWNERS WILL BE NOTIFIED OF THIS CAMPAIGN ON THEIR VEHICLES BY GMC TRUCK (SEE COPY OF OWNER LETTER INCLUDED WITH THIS BULLETIN). A LISTING OF OWNER NAMES AND ADDRESSES HAS BEEN FURNISHED TO THE INVOLVED DEALERS TO ENABLE DEALERS TO FOLLOW UP WITH OWNERS INVOLVED IN THIS CAMPAIGN. THIS LISTING MAY CONTAIN OWNER NAMES AND ADDRESSES OBTAINED FROM STATE MOTOR VEHICLE REGISTRATION RECORDS. THE USE OF SUCH MOTOR VEHICLE REGISTRATION DATA FOR ANY OTHER PURPOSE IS A VIOLATION OF LAW IN SEVERAL STATES. ACCORDINGLY, YOU ARE URGED TO LIMIT THE USE OF THIS LISTING TO THIS CAMPAIGN. SERVICE INFORMATION FOLLOW THE CHART TO DETERMINE YOUR INVOLVEMENT. STATUS CORRECTION DEALER DOES NOT HAVE VEHICLE CAN BE TAKEN TO A DDAD DISTRIBUTOR DDAD ALLISON TRANSMISSION FOR REPAIR, OR TRANSMISSION CAN BE REMOVED AGREEMENT. FROM VEHICLE AND TAKEN TO AN AUTHORIZED DDAD DRISTRIBUTOR TO HAVE VALVE BODY AND CONVERTER REBUILT TO SPECIFICATIONS. DEALER HAS MAINTENANCE VEHICLE CAN BE TAKEN TO A DDAD DISTRIBUTOR SERVICE OPERATIONS, FOR REPAIR, OR TRANSMISSION CAN BE REMOVED DESIGNATED RESPONSIBILITY FROM VEHICLE AND SENT TO A DDAD FOR THE MT 643. DISTRIBUTOR. IF ELECTED, AFTER THE TRANS- MISSION IS REMOVED BY DEALER, REMOVE VALVE BODY AND CONVERTER TO BE SENT TO A DDAD DISTRIBUTOR FOR REPAIR AND CALIBRATION. DEALER IS OVERHAUL SERVICE CAMPAIGN CAN BE COMPLETED AT DEALERSHIP. OPERATION, DESIGNATED VALVE BODY MUST BE CALIBRATION TESTED BY RESPONSIBILITY FOR THE DDAD DISTRIBUTOR. MT 643. SERVICE PROCEDURE FOLLOW THE INSTRUCTIONS AS OUTLINED IN THE SERVICE INFORMATION SECTION OF THIS BULLETIN. IF THE TRANSMISSION IS TO BE REPAIRED AT A GMC TRUCK DEALERSHIP WITH A DDAD TRANSMISSION AGREEMENT, REFER TO THE ALLISON TRANSMISSION SERVICE MANUAL SA 1317J FOR THE FOLLOWING MODIDIFICATION PROCEDURES OPERATION SERVICE MANUAL SECTION R & R TRANSMISSION 4-7 R & R TRANS. OIL PAN 5-4 VALVE BODY OVERHAUL/SHIFT 5-5,6-4 SPRING REPLACEMENT MODULATOR CONVERTER R & R AND 5-4,6-3 OVERHAUL, REPLACE STATOR VALVE BODY, TEST 3-10 PARTS INFORMATION PARTS ARE TO BE OBTAINED FROM THE DDAD DISTRIBUTOR IN THE DEALER'S AREA OF RESPONSIBILITY. FOLLOWING IS AN ADD/DELETE LIST WHICH IS TO BE FOLLOWED TO CONVERT THE SUPPLIED TRANSMISSION PART NUMBER 23014313 TO THE PROPER ASSEMBLY PART NUMBER 23040278. QUANTITIES OTHER THAN ONE EACH ARE NOTED. QUANTITY ADD PART NAME DELETE 2 23016564 CONVERTER SEALS 6758036 SEAL RING 24 190139 CONVERTER NUTS 6837540 HOLD SPRING 6837541 23011980 1-2 SHIFT SPRING 23017044 23017028 2-3 SHIFT SPRING 23013272 23013407 3-4 MOD. SLEEVE 3-4 MOD. VALVE 6881033 23013406 3-4 MOD. VALVE 23017047 3-4 SHIFT SPRING 23013271 6880045 1ST TRIM OUTER SPRING 23012937 6885047 2ND TRIM OUTER SPRING 6837692 23013908 2ND TRIM INNER SPRING 6885166 23018733 4TH TRIM OUTER SPRING 6880045 6880118 4TH TRIM INNER SPRING 6885166 23016355 MOD. LOCKUP SPRING 23017029 3RD TRIM INNER SPRING 6836585 23015077 SEPARATOR PLATE KIT* 23019543 6881434 SLATOR ASSEMBLY 6836585 23016682 FILTER AND GASKET KIT 23019201 23013996 MODULATOR BODY 23015348 23013997 MODULATOR VALVE 23013764 *FOLLOW INSTRUCTION SHEET IN KIT TO DRILL SEPARATOR PLATE. USE CONFIGURATION SPECIFIED FOR P/N 23013812 WITH ADJUSTABLE LOCK UP TORQUE CONVERTER. WARRANTY INFORMATION DEALERS SHOULD SUBMIT AN ACCURATELY FILLED OUT GMC TRUCK WARRANTY REPAIR ORDER ON EACH VEHICLE COMPLETED UNDER THIS CAMPAIGN. LABOR OPERATION **SUBLET *TIME TROUBLE NUMBER DESCRIPTION ALLOWANCE ALLOWANCE CODE V3270 DELIVER TRUCK TO DDAD -- 1.0 HR. 96 DISTRIBUTOR FOR CAMPAIGN REPAIR V3271 R & R TRANSMISSION -- 8.2 HR. 96 & DELIVER TRANSMISSION TO DDAD DISTRIBUTOR FOR CAMPAIGN REPAIR ADD TO R & R VALVE 1.6 HR. BODY CONVERTER, MODULATOR & FILTER V3272 R & R TRANSMISSION -- 11.7 HR. 96 AND MODIFY ACCORDING TO INSTRUCTIONS IN BULLETIN. *FOR DEALER TO RECEIVE ADMINISTATIVE TIME ALLOWANCE ASSOCIATED WITH THIS CAMPAIGN, ADD 0.1 HR. TO THE LABOR OPERATION TIME ALLOWANCE. **THE AMOUNT TO BE ENTERED IN THE NET ITEM COLUMN OF THE WARRANTY CLAIM, CODED S FOR SUBLET. THIS WILL BE THE TOTAL ACTUAL CHARGE BY THE DDAD DISTRIBUTOR TO PERFORM THE CAMPAIGN MODIFICATION. LABOR OPERATION WITH LABOR OPERATION AS SHOWN SUBLET WILL INCLUDE V3270 DDAD DISTRIBUTOR TOTAL PARTS & LABOR V3271 DDAD DISTRIBUTOR TOTAL PARTS & LABOR V3272 DDAD DISTRIBUTOR PARTS COST & VALVE BODY CALIBRATION CAMPAIGN IDENTIFICATION LABEL EACH VEHICLE MODIFIED IN ACCORDANCE WITH THE INSTRUCTIONS OUTLINED IN THIS PRODUCT CAMPAIGN BULLETIN WILL REQUIRE A "CAMPAIGN IDENTIFICATION LABEL." EACH LABEL PROVIDES A SPACE TO INCLUDE THE FIVE (5) DIGIT DEALER CODE OF THE DEALER PERFORMING THE CAMPAIGN SERVICE. THIS INFORMATION MAY BE INSERTED WITH A TYPEWRITER OR BALL POINT PEN. EACH "CAMPAIGN IDENTIFICATION LABEL" IS TO BE LOCATED ON THE RADIATOR CORE SUPPORT IN AN AREA WHICH WILL BE VISIBLE WHEN THE VEHICLE IS BROUGHT IN FOR PERIODIC SERVICING BY THE OWNER. APPLY "CAMPAIGN IDENTIFICATION LABEL" ONLY ON A CLEAN, DRY SURFACE. ADMINISTRATIVE PROCEDURE PROCEDURES COVERING THIS CAMPAIGN ARE OUTLINED IN SECTION V OF YOUR DEALERSHIP'S "GMC TRUCK CLAIMS PROCESSING MANUAL" #SD8519.

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.