Vibration/Buzz/Rattle in Rear Window Shelf Trim Panel Area When Radio Volume/Bass Set High (Install Rear Window Panel Braces)

Some customers may comment on a vibration/buzz/rattle in the rear window shelf trim panel area whenever the radio volume or bass setting is on high.

This condition may be due to the energy output from the speaker causing the nearby panel components to vibrate/rattle whenever the radio volume or bass setting is on high.

Install a LH (1) and a RH (2) rear window panel brace assembly.

1. Remove the rear window shelf trim panel. Refer to Trim Panel Replacement-Rear Window Shelf in the Interior Trim sub-section of the Service Manual or SI Document ID #730411.
2. Remove the RH seat belt retractor.



3. Remove the rear speaker's two front retaining nuts (4).
4. Loosen the rear speaker's two rear retaining nuts (3).
5. Lift and support the forward edge of the rear speaker.
6. Ensure the braces are free of grease.

Important: Once the brace has been positioned, do NOT pull away from the panel. If repositioning is necessary, slide the brace against the shelf panel.




7. Apply GM® Metal Patch Panel Adhesive Fast Set, P/N 12378566 (in Canada, use P/N 88901674) , to the LH Rear Window Panel Brace, P/N 25760577, along the areas indicated in the illustration.



8. Quickly set in place the LH brace along the LH side of the rear speaker's attachment platform (6) and over the front rail of the shelf panel (5).
9. Apply even pressure along the entire brace. Ensure to maintain proper positioning of the brace.



10. Apply GM® Metal Patch Panel Adhesive Fast Set, P/N 12378566 (in Canada, use P/N 88901674), to the RH Rear Window Panel Brace, P/N 25760576, along the areas indicated in the illustration.



11. Quickly set in place the RH brace along the RH side of the rear speaker's attachment platform and over the front rail of the shelf panel (5).
12. Apply even pressure along the entire brace. Ensure to maintain proper positioning of the brace.
13. Install the rear speaker's front retaining nuts.
14. Tighten the rear speaker's rear retaining nuts.
15. Install the RH seat belt retractor
16. Install the rear window shelf trim panel. Refer to Trim Panel Replacement-Rear Window Shelf in the Interior Trim sub-section of the Service Manual or SI Document ID #730411.

Parts are currently available from GMSPO.

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