WIND WHISTLING NOISE FROM OUTSIDE REAR VIEW MIRRORS. GMC Truck S15 Pickup - 2WD 1994

For 1990-2009 cars

# WIND WHISTLING NOISE FROM OUTSIDE REAR VIEW MIRRORS

#### SUBJECT: WIND WHISTLING NOISE FROM OUTSIDE REAR VIEW MIRRORS (INSTALL MIRROR GASKET KITS)

#### MODELS: 1994-95 CHEVROLET AND GMC TRUCK S/T PICKUPS 1995 CHEVROLET AND GMC TRUCK S/T UTILITIES BUILT PRIOR TO THE FOLLOWING VIN BREAKPOINTS:

PLANT DIVISION VIN LINDEN GMC SK519044 MORAINE GMC S2510556 SHREVEPORT GMC S8510188 LINDEN CHEVROLET SK169768 MORAINE CHEVROLET S2129710 SHREVEPORT CHEVROLET S8141358

#### CONDITION:

SOME OWNERS MAY COMMENT THAT THEY HEAR A WHISTLING NOISE FROM OUTSIDE THE SIDE WINDOWS AT HIGHWAY SPEEDS. THE PASSENGER SIDE NOISE IS USUALLY MORE PREVALENT.

#### CAUSE:

WIND PENETRATES THE HORIZONTAL AND VERTICAL "BREAK-AWAY" GAPS ON THE OUTSIDE REAR VIEW MIRRORS CAUSING A WHISTLING SOUND.

#### CORRECTION:

TO REDUCE THIS WIND NOISE, REMOVE THE MIRROR HEAD FROM THE MIRROR BASE AND INSTALL HORIZONTAL AND VERTICAL GASKETS AT THE "BREAK-AWAY" GAPS.

SERVICE PROCEDURE

1. PLACE ONE HAND ON THE LOWER OUTBOARD CORNER OF THE MIRROR HEAD, THEN PLACE THE OTHER HAND ON THE UPPER INBOARD CORNER OF THE MIRROR HEAD. (FIGURE 1) 2. APPLY FIRM SHARP UPWARD PRESSURE WITH THE HAND AT THE LOWER OUTBOARD CORNER OF THE MIRROR HEAD. THIS ACTION IS NECESSARY TO OVERCOME THE SNAP-ON LIP INSIDE THE MIRROR HEAD. 3. ONCE THE SNAP-ON LIP HAS BEEN OVERCOME AND THE MIRROR HAS BEEN LOOSENED, USE A SEE-SAWING MOVEMENT TO WORK THE MIRROR HEAD UPWARD ALONG ITS INTERNAL POST.

#### IMPORTANT: IT IS NOT NECESSARY TO DISCONNECT ANY WIRES LOCATED IN THE POWER MIRROR HEAD.

4. CLEAN THE "BREAK-AWAY" GAP AREA ON THE MIRROR HEAD AND ON THE MIRROR BASE (A SOAP AND WATER SOLUTION IS ACCEPTABLE). 5. DRY THE AREA THOROUGHLY TO ALLOW FOR MAXIMUM GASKET ADHESION. 6. APPLY ONE GASKET TO THE FORWARD-FACING HORIZONTAL SURFACE OF THE MIRROR BASE, USING THE CUT-OUT SLOTS AS LOCATORS. (FIGURE 2, ITEM 1) 7. APPLY ONE GASKET TO THE VERTICAL SURFACE OF THE MIRROR HEAD USING THE TWO LOCATOR TABS AS GUIDES. (FIGURE 3)

#### IMPORTANT: FOR EASE OF INSTALLATION, IT IS SIMPLEST TO START WITH THE WIDE END OF THE VERTICAL GASKET.

8. INJECT AN EXPANDABLE-TYPE INSULATING FOAM (KWIK FOAM FROM DAP OR EQUIVALENT) INTO THE MIRROR BASE POST SO THAT IT IS APPROXIMATELY 25% FULL. WHEN THE FOAM EXPANDS, IT WILL PREVENT A "POP BOTTLE-TYPE" WHISTLING NOISE. THIS FOAM CAN BE PROCURED LOCALLY AT MOST MAJOR HARDWARE STORES OR HOME CENTERS. (FIGURE 2, ITEM 2) 9. REINSTALL THE MIRROR HEAD ON THE BASE.

#### IMPORTANT: IT MAY BE NECESSARY TO USE A FIRM SHARP IMPACT (WITH THE EDGE OF THE HAND) AT THE BREAKAWAY GAP TO PROPERLY SEAT THE MIRROR BACK ON THE BASE.

10. REPEAT STEPS 1-9 FOR THE OTHER OUTSIDE REAR VIEW MIRROR.

PARTS INFORMATION

P/N DESCRIPTION QTY 15724755 OUTSIDE REAR VIEW MIRROR GASKET SERVICE KIT (LEFT) 1 15724756 OUTSIDE REAR VIEW MIRROR GASKET SERVICE KIT (RIGHT) 1 PROCURE LOCALLY EXPANDABLE-TYPE INSULATING FOAM AS NEEDED (KWIK FOAM FROM DAP OR EQUIVALENT)

PARTS ARE EXPECTED TO BE AVAILABLE FROM GMSPO ON 7/31/95.

WARRANTY INFORMATION

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OP DESCRIPTION LABOR TIME R3420 GASKET, MIRROR HEAD - INSTALL (BOTH SIDES) 0.3 HR.

FIGURES: 3

CAPTIONS: FIGURE 1 - MIRROR HEAD REMOVAL FIGURE 2 - MIRROR BASE POST AND HORIZONTAL GASKET PLACEMENT FIGURE 3 - VERTICAL GASKET PLACEMENT

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.