TCC SHUDDER/VIBRATION/ CHUGGLE/SURGE/MISS

SUBJECT: TCC SHUDDER/VIBRATION/CHUGGLE/SURGE/MISS OR FISH BITE WITH NO DTC'S PRESENT (DIAGNOSE/REPLACE DRIVE LINK ASSEMBLY)

MODELS: 1998 CHEVROLET MALIBU 1998 OLDSMOBILE CUTLASS WITH HYDRA-MATIC 4T40-E TRANSAXLE (RPO MN4) AND 3.1L ENGINE (VIN M - RPO L82)

CONDITION:

(SEE FIGURE 1) SOME OWNERS OF VEHICLES WITH HYDRA-MATIC 4T40-E TRANSAXLES BUILT BETWEEN AUGUST 27, 1997 (JULIAN DATE 239) AND DECEMBER 18, 1997 (JULIAN DATE 352) MAY EXPERIENCE A VIBRATION PHENOMENON THAT CAN BE DESCRIBED AS TCC SHUDDER/VIBRATION/CHUGGLE/SURGE/MISS OR FISH BITE. THIS VIBRATION WILL OCCUR IN 3RD OR 4TH GEAR WITH TCC APPLIED UNDER A LIGHT ACCELERATION, AT APPROXIMATELY 1600 ENGINE RPM.

CAUSE:

THE ABOVE CONDITION MAY BE DUE TO DRIVE LINK ASSEMBLIES WITH EXCESSIVE LINK TO LINK VARIATION. THIS VARIATION CAN CAUSE A NON-UNIFORM ROTATION OF THE OUTPUT SPROCKET WHICH THEN PRODUCES A VIBRATION THROUGHOUT THE VEHICLE DRIVELINE.

CORRECTION:

(SEE FIGURE 2) ROAD TEST THE VEHICLE AND VERIFY THAT A VIBRATION OR MISS CONDITION EXISTS AS LISTED UNDER "CONDITION".

FOLLOW NORMAL DIAGNOSIS PROCEDURES FOR ENGINE VIBRATION OR MISS CONDITIONS. IF THE CONDITION IS NOT CORRECTED, VERIFY THAT THE CRUISE CONTROL BRAKE SWITCH IS FUNCTIONING PROPERLY BY BYPASSING TERMINAL A TO B OF THE CRUISE CONTROL BRAKE SWITCH.

IF THE CONDITION IS CORRECTED, FOLLOW THE CRUISE CONTROL DIAGNOSTIC PROCEDURE LOCATED IN THE SERVICE MANUAL. IF THE CONDITION IS NOT CORRECTED, INSPECT THE DRIVELINK ASSEMBLY (36) BY FIRST FINDING THE COLORED (BLUE) DRIVE LINK. THEN INSPECT FOR A HAND SCRIBED OR ETCHED MARKING ON THE DRIVE LINK NEXT TO (EITHER SIDE OF) THE COLORED DRIVE LINK. DRIVE LINK ASSEMBLIES WITH THIS HAND SCRIBED OR ETCHED MARKING MAY CAUSE THE VIBRATION PHENOMENON AS LISTED UNDER "CONDITION" AND SHOULD BE REPLACED.

REFER TO THE UNIT REPAIR SECTION OF THE SERVICE MANUAL FOR THE PROPER PROCEDURE.

PART INFORMATION:

PART NUMBER DESCRIPTION 24200738 DRIVE LINK ASSEMBLY

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR CODE: K7520 LABOR TIME: USE PUBLISHED LABOR OPERATION TIME.

FIGURES: 2 ATTACHMENTS: 0

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.

COPYRIGHT 1998. GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.