GM Service Manual Online
For 1990-2009 cars only

VIBRATION, KNOCKING - WHEN VEHICLE IS PUT IN REVERSE

SUBJECT: VIBRATION, KNOCKING - TAPPING NOISE WHEN VEHICLE IS PUT INTO REVERSE (GRIND TORQUE STRUT TO ENGINE MOUNT BOLT)

MODELS: 1994-95 BUICK SKYLARK 1994-95 OLDSMOBILE ACHIEVA 1994-95 PONTIAC GRAND AM WITH 2.3L ENGINE (VINS A, D, 3 - RPOS LG0, LD2, L40) AND 3.1L ENGINES (VIN M - RPO L82) AND 3T40 AND 4T60-E TRANSAXLES (RPOS MD9 AND M13)

CONDITION:

SOME OWNERS MAY COMMENT ON A DRIVETRAIN VIBRATION AND KNOCKING-TAPPING NOISE WHEN THE VEHICLE IS PUT INTO REVERSE. THE NOISE WILL ORIGINATE FROM THE RIGHT FRONT OF THE VEHICLE.

CAUSE:

THE TORQUE STRUT TO ENGINE MOUNT BOLT CONTACTS THE FRONT SUSPENSION SUPPORT ON THE VEHICLE AND EMITS THE VIBRATION - KNOCKING/TAPPING SOUND.

CORRECTION:

INSPECT THE TAPERED END OF THE TORQUE STRUT TO ENGINE MOUNT BOLT FOR MARKS INDICATING CONTACT WITH THE FRONT SUSPENSION SUPPORT.

GRIND TORQUE STRUT TO ENGINE MOUNT BOLT OFF FLUSH WITH THE NUT WELDED TO THE FRONT SUSPENSION SUPPORT OF THE VEHICLE AS FOLLOWS:

1. SCRIBE THE TAPERED END PORTION OF THE BOLT SO MARK IS FLUSH WITH THE NUT WELDED TO THE VEHICLE FRONT SUSPENSION SUPPORT.

2. REMOVE TORQUE STRUT TO ENGINE MOUNT BOLT FROM VEHICLE.

3. GRIND THE BOLT OFF WHERE SCRIBE MARK WAS MADE.

4. INSTALL BOLT BACK INTO VEHICLE AND TORQUE TO SPECS.

5. TEST VEHICLE FOR CORRECTION OF CONDITION.

WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OPERATION NUMBER: J1520 LABOR TIME: 0.4 HRS.

FIGURES: 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 1995 GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.