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Makes 🢒 GMC_Truck 🢒 2007 🢒 Sierra - 4WD 🢒 Bulletins 🢒 Hood Flutter, Shake or Vibration at Highway Speeds (Apply Flexible Adhesive Sealer Between Inner and Outer Panels)

Hood Flutter, Shake or Vibration at Highway Speeds (Apply Flexible Adhesive Sealer Between Inner and Outer Panels)

Subject:Hood Flutter, Shake or Vibration at Highway Speeds (Apply Flexible Adhesive Sealer Between Inner and Outer Panels)

Models:2007 GMC Sierra


Condition

Some customers may comment on the vehicle hood fluttering, vibrating or displaying visible motion at highway speeds.

Cause

The inner and outer hood panels may not be sufficiently bonded together at all points. At highway speeds, the sheet metal may be able to flutter at some locations.

Correction

Apply flexible adhesive sealer between the inner and outer panels. The procedure below outlines the proper repair instructions. The accompanying illustration shows the most likely areas that may be the source of the fluttering.

Important: The hood fluttering or vibration DOES NOT indicate that any adjustment of the hood latch, striker, or bumpers is needed.

  1. Open the hood.
  2. Remove the eight plastic fasteners retaining the underhood insulation pad using a trim tool.
  3. Remove the underhood insulation pad.
  4. Cover the engine and the cowl area with a blanket, towel or other protective covering. Panel sealer/foam may drip while being applied.
  5. Refer to the picture below. In all cases you will be filling the void between the inner and outer panels to prevent the metal fluttering. The arrows indicate the areas most likely to require additional bonding. Examine the underhood panel for signs of the original factory material exhibiting shrinkage or insufficient application.

    6. GMC Sierra
    Object Number: 1974234 Size: SH
  6. Using a minimal expansion foam adhesive/sealer such as 3M 8463 Automix Flexible Foam, Kent Automotive P10601 (or equivalent), fill the voids between the inner and outer hood panels as shown in the illustration. Keep the tip of the applicator right up against the panel in order to allow the material to flow in between the panels.

    7. Important: While most of the areas to bond will be covered by the underhood insulation pad, maintain a neat appearance in the areas closest to the vehicle cowl area. The underhood pad will only cover part of the area nearest the cowl.

  7. Replace the underhood insulation pad.
  8. Install the eight retainers.
  9. Remove the blanket covering the engine and fenders.
  10. Inspect for and clean up any dripped sealer.
  11. Close the hood.

Parts Information

Kent Automotive Flexible Foam/Sound Deadener #P10601 can be ordered directly at 1-800-654-6333 (In Canada 1-800-563-1717).

3M products may be purchased through your local distributor. Information about 3M product retailers in your area may be obtained at 1-800-364-3577 (U.S. and Canada).

Part Number

Description

Material Allowance

8463

*3M Automix Flexible Foam

$14.00** (U.S.)

$19.45 (Canada)

P10601

*Kent Automotive Flexible Foam / Sound Deadener

*We believe this source and their products to be reliable. There may be additional manufacturers of such products/material. General Motors does not endorse indicate any preference for or assume any responsibility for the products or material from this firm or for any such items that may be available from other sources.

**This allowance is for 1 vehicle. Each two part caulk tube is sufficient to do a minimum of 3 vehicles.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation

Description

Labor Time

B9823*

Bond, Inner and Outer Hood Panels

0.4 hr

*This labor operation number is for bulletin use only. This number will not be published in the Labor Time Guide.