CAMPAIGN-AXLE SHAFT END PLAY CHECKING PROCEDURE

CONDITION THIS NOTICE IS SENT TO YOU PURSUANT TO AN AGREEMENT OF SETTLEMENT BETWEEN THE DEPARTMENT OF TRANSPORTATION AND GENERAL MOTORS CORPORATION. IN APRIL 1984, THE NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION (NHTSA) MADE AN INITIAL DETERMINATION THAT A DEFECT WHICH RELATES TO MOTOR VEHICLE SAFETY EXISTS IN CERTAIN 1978-80 GM "A" SERIES VEHICLES. SPECIFICALLY, THE NHTSA DETERMINED, AT THAT TIME, THAT SOME OF THESE VEHICLES "MAY BE MANUFACTURED WITH REAR AXLE SHAFTS WITH THIN END BUTTONS" AND THAT "THIS CONDITION MAY RESULT IN DISENGAGEMENT OR SEPARATION OF THE AXLE SHAFT AND WHEEL ASSEMBLY FROM THE VEHICLE, WHICH COULD LEAD TO LOSS OF VEHICLE CONTROL, ACCIDENTS, INJURIES, DEATH OR PROPERTY DAMAGE." DESPITE GENERAL MOTORS CONTINUING DISAGREEMENT WITH THAT PRELIMINARY FINDING, GENERAL MOTORS DESIRES TO RESOLVE ANY CONCERNS IN THE MINDS OF OUR CUSTOMERS AND TO ADDRESS NHTSA'S CONTINUING CONCERNS WITH RESPECT TO THE POSSIBILITY OF FUTURE REAR AXLE SEPARATIONS INVOLVING AXLES PRODUCED AT GM'S BUFFALO AXLE PLANT. ACCORDINGLY, THE DEALERS ARE REQUIRED TO INSPECT AND DETERMINE IF THE OWNER'S VEHICLE HAS AN AXLE PRODUCED AT THE BUFFALO AXLE PLANT. IF SO, MAKE THE REAR AXLE MEASUREMENTS AND REPAIRS OR MODIFY AS COVERED IN THE PROCEDURES WHICH ARE ATTACHED. VEHICLES INVOLVED INVOLVED ARE CERTAIN 1978-1979-1980 "A" MODELS PRODUCED AT THE FOLLOWING ASSEMBLY PLANTS: YEAR MODEL ASSY. PLANT BEGINNING UP TO AND INCL. 1978,79,80 ALL "A" ARLINGTON (R) START OF PROD. END OF PROD. 1978,79,80 ALL "A" DORAVILLE (D) SOP EOP 1978,79 "A" WAGON ONLY FRAMINGHAM (G) SOP EOP 1980 ALL "A" FRAMINGHAM (G) SOP EOP 1979,80 ALL "A" STE. THERESE (2) SOP EOP DEALER ACTION DEALERS ARE TO SERVICE ALL VEHICLES SUBJECT TO THIS FIELD PROCEDURE AT NO CHARGE TO THE OWNER, REGARDLESS OF MILEAGE, AGE OF VEHICLE, OR OWNERSHIP, FROM THIS TIME FORWARD. IN ADDITION, WHENEVER A VEHICLE SUBJECT TO THIS FIELD PROCEDURE IS TAKEN INTO YOUR DEALERSHIP FOR SERVICE OR INTO YOUR USED CAR INVENTORY, YOU SHOULD BE SURE THAT THIS PROCEDURE OR ANY CAMPAIGN REQUIRED BY C.R.I.S. (COMPUTRIZED RECALL INFORMATION SYSTEM) OR OTHER DIVISIONAL INFORMATION IS COMPLETED PRIOR TO RELEASE OR RESALE OF THE VEHICLE. SERVICE PROCEDURE 1. RAISE THE VEHICLE ON A HOIST. LOCATE THE AXLE IDENTIFICATION INFORMATION STAMPED ON THE RIGHT FRONT INBOARD SIDE OF THE AXLE TUBE. REFER TO FIGURE 1. IT MAY BE NECESSARY TO WIRE BRUSH THE AREA TO MAKE IT LEGIBLE. 2. IF THE MANUFACTURE CODE INDICATES A "C" AS SHOWN IN FIGURE 1, GO TO STEP 3 OF THIS PROCEDURE. IF OTHER THAN A "C" PROCEED TO STEP 13. 3. IF THE VEHICLE HAS LESS THAN 20,000 MILES GO DIRECTLY TO STEP 8. IF THE VEHICLE HAS GREATER THAN 20,000 MILES, MOUNT A DIAL INDICATOR ON THE AXLE HOUSING BEHIND EITHER REAR WHEEL. REST THE INDICATOR POINT AGAINST THE BACK SIDE OF THE WHEEL OR THE EDGE OF THE BRAKE DRUM. 4. MEASURE THE END PLAY OF EACH AXLE SHAFT BY GRASPING THE TIRE WITH BOTH HANDS AND PUSHING OUTBOARD UNTIL AXLE SHAFT IS FELT TO BOTTOM. ZERO INDICTOR. REFER TO FIGURE 2. 5. AGAIN GRASP THE TIRE WITH BOTH HANDS AND PULL INBOARD UNTIL AXLE SHAFT IS FELT TO BOTTOM. READ THE INDICATOR, MAKING CERTAIN THAT THE READING IS WITHIN THE RANGE OF THE INDICATOR. RECORD THE INDICATOR READING OF EACH REAR AXLE. REFER TO FIGURE 2. 6. THE READINGS OBTAINED IN STEP 5 SHOULD BE COMPARED WITH THE SPECIFICATIONS IN CHART 1. CHART 1 MAXIMUM ALLOWABLE END PLAY FOR EITHER AXLE SHAFT MILEAGE PERFORM STEP 8 IF END PLAY IS: 20,000 TO 30,000 GREATER THAN .030 30,000 TO 45,000 GREATER THAN .040 45,000 OR OVER GREATER THAN .055 7. IF THE END PLAY READING OF BOTH AXLE SHAFTS EQUALS OR IS LESS THAN THE END PLAY SPECIFICATION IN CHART 1, AT THE MILEAGE INDICATED, NO ADDITIONAL CHECKING IS REQUIRED. PROCEED TO STEP 13. IF THE END PLAY READING OF EITHER AXLE SHAFT EXCEEDS THE END PLAY SPECIFICATION IN CHART 1, AT THE INDICATED MILEAGE THE FOLLOWING STEPS SHOULD BE PERFORMED. 8. REMOVE THE AXLE CARRIER INSPECTION COVER AND DRAIN THE LUBRICANT. 9. EACH AXLE SHAFT BUTTON THICKNESS MUST BE MEASURED USING THE SPECIAL AXLE BUTTON GAGE TOOL PROVIDED. IN ORDER TO MEASURE BUTTON THICKNESS, THE AXLE SHAFTS MUST BE PUSHED FULLY INBOARD AND THE "C" LOCK MUST BE ROTATED SO THAT OPENING FACES REARWARD TO ALLOW ACCESS FOR THE GAGE. SEE FIGURES 3 AND 4. THE BUTTON THICKNESS MUST BE CHECKED USING BOTH ENDS OF THE GAGING TOOL. REFER TO CHART II TO DETERMINE THE ACTION REQUIRED. 10. IF NECESSARY, THE AXLE SHAFT AND THE DIFFERENTIAL PINION SHAFT SHOULD BE REPLACED USING THE PROCEDURE IN THE APPLICABLE SERVICE MANUAL. FOR PART NUMBERS, REFER TO "PARTS INFORMATION" SECTION OF THIS BULLETIN. NOTE: SHOULD THE PINION SHAFT LOCK SCREW BREAK WHILE REMOVING, REFER TO THE SEPTEMBER 1983 SERVICE GUILD ARTICLE FOR REMOVAL OF THE PINION CROSS SHAFT. CHART II PINION SHAFT AND AXLE SHAFT REPLACEMENT AXLE SHAFT BUTTON THICKNESS GREATER THAN LESS THAN MILEAGE .190 .160" - .190" .160"

0 TO 20,000 REPLACE PINION REPLACE PINION REPLACE PINION AND SHAFT SHAFT AXLE SHAFT

20,000 TO NO PART REPLACE PINION REPLACE PINION AND 75,000 REPLACEMENT SHAFT AXLE SHAFT

OVER 75,000 NO PART NO PART REPLACE PINION AND REPLACEMENT REPLACEMENT AXLE SHAFT 11. AFTER COMPLETING ABOVE STEPS, VERIFY THAT AXLE SHAFT END PLAY IS LESS THAN THE MAXIMUM ALLOWED IN CHART III. IF IT IS NOT, DETERMINE CAUSE OF END PLAY, IF POSSIBLE, AND CONTACT YOUR ZONE OFFICE FOR INSTRUCTION. CHART III MAXIMUM ALLOWABLE END PLAY FOR EITHER AXLE SHAFT AFTER PERFORMING ABOVE PROCEDURE MILEAGE STANDARD AXLE LIMITED SLIP TO 45,000 .040 .065 OVER 45,000 .055 .085 12. INSTALL THE AXLE CARRIER COVER USING A NEW COVER GASKET AND FILL HOUSING WITH THE PROPER LUBRICATION. LOWER HOIST. 13. RAISE HOOD TO INSTALL A COMPLETION IDENTIFICATION LABEL ON THE RADIATOR FAN SHOUD. EACH VEHICLE MODIFIED IN ACCORDANCE WITH THE INSTRUCTIONS OUTLINED IN THIS SERVICE PROCEDURE WILL REQUIRE AN IDENTIFICATION LABEL. EACH LABEL PROVIDES A SPACE TO INCLUDE THE BULLETIN NUMBER, THE FIVE (5) DIGIT DEALER CODE OF THE DEALER PERFORMING THE SERVICE, AND THE DATE THE VEHICLE WAS SERVICED. THIS INFORMATION MAY BE INSERTED WITH A TYPEWRITER OR BALLPOINT PEN. INSTALL THE LABEL ON THE RADIATOR BAFFLE WHERE IT IS READILY VISIBLE. CLOSE HOOD. PARTS INFORMATION VERY FEW VEHICLES WILL REQUIRE PARTS (1 IN EVERY 200 VEHICLES INSPECTED). THEREFORE, LIMIT THE NUMBER OF PARTS BEING ORDERED TO PREVENT A PARTS SHORTAGE CONDITION. TO ENSURE THAT PARTS WILL BE OBTAINED AS SOON AS POSSIBLE, THEY SHOULD BE ORDERED FROM WDDGM ON A C.I.O. ORDER WITH NO SPECIAL INSTRUCTION CODE, BUT ORDER ON AN ADVISE CODE (2). DESCRIPTION PART NUMBER QUANTITY AXLE 551818 AS REQUIRED PINION SHAFT - USE FOR STD. OR G80 LIMITED SLIP 22507586 1 DIFFERENTIAL COVER GASKET 551651 1 LUBRICANT 1052271 1 3/4 QT. LUBRICANT ADDITIVE (LIMITED SLIP ONLY) 1052358 4 OZ. PARTS ARE TO BE RETAINED FOR DISPOSITION BY ZONE PERSONNEL

WARRANTY INFORMATION OPERATION FAILURE CODE LABOR OP. LABOR HRS. - INSPECT AXLE CODE, NO FURTHER ACTION REQUIRED 96 V2470 .3 - INSPECT AXLE CODE AND CHECK END PLAY 96 V2471 .3 - INSPECT AXLE CODE, CHECK END PLAY AND BUTTON THICKNESS 96 V2472 .5 - INSPECT AXLE CODE, CHECK END PLAY AND BUTTON THICKNESS. REPLACE ONE OR TWO AXLE SHAFTS AND/OR PINION SHAFT. .1 HOUR FOR CLERICAL ADMINISTRATION MAY BE ADDED TO THE ABOVE OPERATION. PARTS WILL BE CREDITED AT DEALER COST PLUS 30%. REFER TO PARTS INFORMATION SECTION OF THIS BULLETIN.

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.