POWER STEERING SHUDDER OR RACK RATTLE (INSTALL & REPL. HOSE). Chevrolet Corsica 1992

REVISION: 03/23/94

THIS BULLETIN IS BEING REVISED TO INCLUDE CANADIAN VEHICLES. ORIGINAL BULLETIN WAS RESTRICTED TO U.S. VEHICLES ONLY. ----------------------------------------------------------------------

SUBJECT: POWER STEERING SHUDDER OR STEERING RACK RATTLE (INSTALL RETURN HOSE RESTRICTOR OR REPLACE POWER STEERING INLET HOSE - "J" SERIES ONLY)

MODELS: 1992-93 BUICK SKYLARK 1992-93 CHEVROLET CAVALIER, CORSICA AND BERETTA 1992-93 OLDSMOBILE ACHIEVA 1992-93 PONTIAC SUNBIRD AND GRAND AM

CONDITION:

POWER STEERING GEAR RACK RATTLE - SOME VEHICLES MAY EXHIBIT A POWER STEERING RATTLE. THIS RATTLE NOISE IS MORE NOTICEABLE WHEN THERE ARE SHARP STEERING WHEEL INPUTS, SUCH AS CROSSING OVER RAILROAD TRACKS OR POTHOLES. VERIFICATION OF STEERING RACK RATTLE ROOT CAUSE IS TO REPEAT MANEUVER WITH VEHICLE IN NEUTRAL AND THE ENGINE OFF. IF NOISE IS STILL PRESENT, THEN STEERING RACK IS NOT THE ROOT CAUSE.

POWER STEERING SHUDDER - VIBRATION IS HEARD AND/OR FELT IN THE FRONT OF THE VEHICLE WHEN TURNING THE STEERING WHEEL SLOWLY. THIS VIBRATION IS MORE NOTICEABLE WHEN THE CAR IS STOPPED OR DURING SLOW PARKING MANEUVERS. THIS CONDITION MAY BE MORE NOTICEABLE WHEN THE CAR IS IN DRIVE AND THE BRAKE PEDAL IS APPLIED. THIS CONDITION MAY SOMETIMES ALSO BE FELT THROUGH THE BRAKE PEDAL OR STEERING WHEEL. THESE SYMPTOMS ARE THE MOST NOTICEABLE WHEN APPROACHING THE END OF THE STEERING TRAVEL.

CAUSE:

RACK RATTLE IS HYDRAULIC MOVEMENT OF THE STEERING VALVE THAT OCCURS WHEN ROAD INPUT BACKDRIVES THE STEERING SYSTEM.

SHUDDER OCCURS WHEN STEERING VALVE VIBRATION SENDS IMPULSES TO THE STEERING SYSTEM WHICH ARE THEN TRANSMITTED INTO THE PASSENGER COMPARTMENT.

CORRECTION:

RACK RATTLE ONLY OCCURS ON "L" AND "N" VEHICLES. SHUDDER OCCURS ON "J/L/N" VEHICLES. THIS BULLETIN APPLIES TO 1993 "J/L/N" VEHICLES BUILT PRIOR TO THE VIN BREAKPOINTS LISTED BELOW, 1992 "N" VEHICLES (EXCEPT LG0 AND LG7 ENGINE), "L" CARS (EXCEPT LG0) AND 1992 "J" CARS (SHUDDER ONLY).

L-CAR PY251604 N-CAR (PONTIAC) PC786160 OR PM599379 N-CAR (OLDS) PM034403 N-CAR (BUICK) PC294703 J-CAR WILL IMPLEMENT AT 1994 START OF PRODUCTION

RACK RATTLE OR SHUDDER (EXCEPT J-CAR, LE4):

INSTALL RETURN HOSE RESTRICTOR, P/N 22592200, IN THE INLET TUBE OF THE POWER STEERING FLUID RESERVOIR. PART SHOULD BE PUSHED IN BY HAND UNTIL SNUG, NOT FORCED OR HAMMERED. RETURN HOSE SHOULD BE PUSHED OVER RESTRICTOR AND INLET TUBE AND CLAMPED.

SHUDDER FOR J-CAR, LE4:

REPLACE POWER STEERING INLET HOSE AT THE GEAR WITH HIGH EXPANSION HOSE, P/N 26044374.

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OPERATION NUMBER: T3382 (FOR RACK RATTLE REPAIR ONLY) 0.2 HRS.

LABOR OPERATION NUMBER: E8622 (FOR SHUDDER REPAIR, J-CAR ONLY) USE PUBLISHED LABOR OPERATION TIME

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.