CAMPAIGN:INCORRECT SPEEDOMETER DRIVEN GEAR. Chevrolet Corvette 1981

GENERAL MOTORS HAS DETERMINED THAT SOME 1981 FULL SIZE CHEVROLET MODELS EQUIPPED WITH SEO 9C1 (POLICE PACKAGE), RPO LG4 (305 V8), RPO MV4 (3 SPEED AUTOMATIC) AND RPO GU 4 (3.08 AXLE RATIO) WERE ASSEMBLED AT GMAD JANESVILLE WITH THE INCORRECT SPEEDOMETER DRIVEN GEAR, SLEEVE AND ADAPTER.

THE INCORRECT SPEEDOMETER DRIVEN GEAR WILL RESULT IN THE SPEEDOMETER INDICATING A VEHICLE SPEED WHICH IS APPROXIMATELY 9% SLOWER THAN THE ACTUAL VEHICLE SPEED AND AN ODOMETER READING WHICH IS APPROXIMATELY 9% LESS THAN ACTUAL VEHICLE MILEAGE. TO CORRECT THIS CONDITION, THE SPEEDOMETER DRIVEN GEAR AND SLEEVE WILL BE REPLACED AND THE ADAPTER REMOVED FROM ALL INVOLVED VEHICLES.

VEHICLES INVOLVED

INVOLVED ARE SOME 1981 FULL SIZE CHEVROLET MODELS EQUIPPED WITH SEO 9C1 (POLICE PACKAGE), PRO LG4 (305 V8), RPO MV4 (3 SPEED AUTOMATIC) AND RPO GU4 (3.08 AXLE RATIO) ASSEMBLED AT GMAD JANESVILLE WITHIN THE FOLLOWING VEHICLE IDENTIFICATION NUMBER BREAKPOINTS:

FROM THROUGH

BJ151110 BJ223154

INVOLVED VEHICLES HAVE BEEN IDENTIFIED BY VEHICLE IDENTIFICATION NUMBER COMPUTER LISTINGS. COMPUTER LISTINGS CONTAIN THE COMPLETE VEHICLE IDENTIFICATION NUMBER, OWNER NAME AND ADDRESS DATA, AND ARE FURNISHED TO THE INVOLVED DEALERS WITH THE CAMPAIGN BULLETIN. OWNER NAME AND ADDRESS DATA FURNISHED WILL ENABLE DEALERS TO FOLLOW UP WITH OWNERS INVOLVED IN THIS CAMAPIGN.

THESE LISTINGS 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 FOR THE FOLLOW UP NECESSARY TO COMPLETE THIS CAMPAIGN.

ANY DEALER NOT RECEIVING A COMPUTER LISTING WITH THE CAMPAIGN BULLETIN WAS NOT SHIPPED ANY INVOLVED VEHICLES.

OWNER NOTIFICATION

OWNERS WILL BE NOTIFIED OF THIS CAMPAIGN ON THEIR VEHICLES BY CHEVROLET MOTOR DIVISION (SEE COPY OF OWNER LETTER INCLUDED WITH THIS BULLETIN).

DEALER CAMPAIGN RESPONSIBILITY

THIS RECALL CAMPAIGN IS TO BE PERFORMED AT NO CHARGE TO OWNERS ON ALL AFFECTED VEHICLES REGARDLESS OF TIME, MILEAGE, OR OWNERSHIP. DEALERS ARE TO INSPECT AND CORRECT ALL AFFECTED VEHICLES IN NEW AND USED VEHICLE STOCK PRIOR TO THEIR SALE.

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 CAMAPIGN CORRECTION HAS BEEN MADE.

SERVICE PROCEDURE

1. ELEVATE VEHICLE.

2. DISCONNECT SPEEDOMETER CABLE AT SPEEDOMETER ADAPTER.

3. REMOVE RETAINER BOLT, RETAINER, SPEEDOMETER DRIVEN GEAR ASSEMBLY AND ADAPTER (REF: 1981 CHEVROLET SERVICE MANUAL, PAGE 7A-20, FIGURE 7A-41)

DISCARD DRIVEN GEAR ASSEMBLY AND ADAPTER, PARTS NOT TO BE REUSED.

4. INSTALL NEW "O" RING SEAL, P/N 6264903, TO NEW SLEEVE ASSEMBLY P/N 345215.

5. INSTALL NEW DRIVEN GEAR P/N 3987921 (RED), AND SLEEVE ASSEMBLY, P/N 345215, AND SECURE IN POSITION REUSING REMOVED RETAINER AND RETAINER BOLT. TORQUE RETAINER BOLT TO 36-48 IN.LBS. (4.0-5.5 NM).

6. RECONNECT SPEEDOMETER CABLE TO SPEEDOMETER SLEEVE ASSEMBLY AND LOWER VEHICLE.

7. INSTALL "CAMPAIGN IDENTIFICATION LABEL", ACCORDING TO THE INSTRUCTIONS CONTAINED IN THIS BULLETIN.

PARTS INFORMATION

DEALERS ARE REQUESTED TO ORDER THE PARTS REQUIRED TO COMPLETE THIS CAMPAIGN FROM GENERAL MOTORS WAREHOUSING AND DISTRIBUTION DIVISION.

PART NUMBER QUANTITY PER VEHICLE DESCRIPTION

3987921 1 SPEEDOMETER DRIVEN GEAR (RED) 345215 1 SLEEVE 6264903 1 "O" RING SEAL

CLAIM INFORMATION

SUBMIT A PRODUCT CAMPAIGN CLAIM WITH THE INFORMATION INDICATED BELOW:

PARTS FAILED ** PARTS FAILURE LABOR LABOR *OTHER COUNT PART NO. ALLOWANCE CODE OPERATION HOURS HOURS

3 3987921 00 V0970 .3 .1

DESCRIPTION: REMOVE INCORRECT DRIVEN GEAR AND INSTALL NEW SPEEDOMETER DRIVEN GEAR AND SLEEVE.

* CAMPAIGN ADMINISTRATIVE ALLOWANCE

** THE PARTS ALLOWANCE SHOULD BE THE SUM TOTAL OF THE CURRENT GMWDD DEALER NET PLUS 30% OF ALL PARTS REQUIRED FOR THE REPAIR.

DEALERS WILL AUTOMATICALLY RECEIVE THE CORRECT PARTS AND LABOR ALLOWANCE BASED ON THE LABOR OPERATION PERFORMED.

REFER TO THE CHEVROLET CLAIMS PROCESSING MANUAL FOR DETAILS ON PRODUCT CAMPAIGN CLAIM SUBMISSION.

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 DIGIT DEALER CODE OF THE DEALER PERFORMINT THE CAMPAIGN SERVICE. THIS INFORMATION MAY BE INSERTED WITH A TYPEWRITER OR BALLPOINT PEN.

EACH "CAMPAIGN IDENTIFICAITON 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

REFER TO THE CURRENT CHEVROLET SERVICE POLICIES AND PROCEDURES MANUAL AND CLAIMS PROCESSING MANUAL FOR CAMPAIGN HANDLING AND ADMINISTRATIVE PROCEDURES.

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.