INSTALLATION OF LUGGAGE RACK PROC. FOR REDUCED WIND NOISE

THIS BULLETIN PROVIDES THE CORRECT PROCEDURE FOR INSTALLING ROOF LUGGAGE RACKS ONTO 1992 C/K SUBURBANS, UTILITIES AND M/L VANS. INCORRECT INSTALLATION OF ROOF LUGGAGE RACKS COULD RESULT IN INCREASED WIND NOISE. THIS WIND NOISE MAY BE CAUSED BY AIR FLOW VIBRATING AGAINST THE LUGGAGE RACK CROSS RAILS.

THE ROOF RACK CROSS RAILS HAVE BEEN REDESIGNED FOR THE 1992 M/L VANS. THE NEW DESIGN IS SYMMETRICAL AND ELIMINATES THE NEED FOR POSITIONING THE M/L VAN CROSS RAILS IN A PARTICULAR DIRECTION (FIGURE 1). THE NEW DESIGN HAS SUPERIOR WIND NOISE REDUCTION CHARACTERISTICS.

THE ASSEMBLY AND INSTALLATION PROCEDURES FOR THE ROOF LUGGAGE RACK ON THE 1992 C/K SUBURBAN AND C/K UTILITY HAVE BEEN MODIFIED. BOTH THE POSITION AND DIRECTIONAL PLACEMENT OF THE CROSS RAILS ARE IMPORTANT IN REDUCING WIND NOISE.

INSTALLATION INSTRUCTIONS DESCRIBED BELOW ARE DIVIDED INTO TWO SECTIONS:

- 1992 C/K SUBURBANS AND C/K UTILITIES - 1992 M/L VANS

SERVICE PROCEDURE:

FOR 1992 SUBURBANS AND C/K UTILITIES ONLY

NOTE: THE PROCEDURE FOR INSTALLING ROOF LUGGAGE RACKS ONTO 1992 SUBURBANS AND C/K UTILITIES IS DIFFERENT THAN THE INSTALLATION PROCEDURE FOR OTHER VEHICLES.

ASSEMBLY OF ROOF LUGGAGE RACK

1. INSTALL SLIDERS INTO SLOTS IN SIDE RAIL ASSEMBLY.

2. SECURE FASTENERS (M6 X 1 X 20) INTO SLIDERS AND LOCK PLATES.

3. SLIP SUPPORT ASSEMBLY INTO SIDE RAIL AT ALL FOUR CORNERS.

4. SECURE FASTENERS (M5 X 0.8 X 10) INTO SUPPORT ASSEMBLY.

5. POSITION THE NARROW EDGE OF BOTH FRONT AND REAR CROSS RAILS TOWARD THE FRONT OF THE VEHICLE. A DIRECTIONAL STICKER IS ATTACHED TO THE CROSS RAIL TO PROVIDE ASSISTANCE IN POSITIONING BOTH THE FRONT AND REAR RAILS.

6. FOR SUBURBAN: ALIGN THE FRONT CROSS RAIL WITH THE SECOND SUPPORT (FIGURE 2). FOR UTILITY: POSITION THE FRONT CROSS RAIL 200 MM (8 IN.) BEHIND THE FIRST SUPPORT (FIGURE 4).

7. POSITION THE REAR CROSS RAIL AGAINST THE LAST SUPPORT ASSEMBLY.

8. SLIP CROSS RAILS INTO SLIDER.

9. SECURE FASTENERS (M5 X 0.8 X 10) INTO CROSS RAILS.

10. TORQUE FASTENERS IN SLIDER AND LOCK PLATES TO 2.2 N.M. (20 LBS. IN.).

11. TORQUE FASTENERS IN CROSS RAIL AND SUPPORT ASSEMBLY TO 1.6 N.M. (15 LBS. IN.).

INSTALLATION OF ROOF LUGGAGE RACK

1. PLACE SIDE RAIL SUPPORT GASKETS ONTO THE ROOF OF THE VEHICLE (FIGURES 3 AND 5).

NOTE: POSITION GASKETS SO CARRIER ARROW POINTS OUTWARD.

2. MOUNT ROOF LUGGAGE RACK ONTO SUPPORT GASKETS.

3. SECURE FASTENERS SPECIFIED IN FIGURES 3 AND 5 INTO SIDE RAIL SUPPORTS AND GASKETS.

4. TORQUE FASTENERS TO 2.2 - 3.4 N.M. (20 - 30 LBS. IN.).

5. SECURE RUBBER SIDE RAIL CAP ONTO CENTER SUPPORT (FIGURE 3).

FOR 1985 - 1992 M/L VANS ONLY

TORQUE SPECIFICATIONS AND INSTALLATION INSTRUCTIONS ARE COVERED IN THE INSTRUCTION SHEET CONTAINED WITHIN EACH ROOF RACK KIT.

IMPORTANT: TO REDUCE WIND NOISE IN 1985 - 1992 M/L VANS, THE CROSS RAILS MUST BE INSTALLED EVEN WITH THE CENTER SUPPORTS.

FOR REDUCED WIND NOISE IN 1985 - 1991 M/L VANS, BECAUSE THE CROSS RAILS ARE NOT SYMMETRICAL, THE BLUNT EDGE OF THE CROSS RAILS AND BLUNT EDGE OF THE RUBBER INSERTS MUST FACE THE FRONT OF THE VEHICLE.

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 1991 GMC TRUCK DIVISION, GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.