Subtitled "why does it sound like there's a 14 inch piece of metal rattling around in the back?"

Back

Because there *is* a big hunk of metal rattling around.

I found this after I removed the left plastic cover (the cover over the Suburban furnace).

Pictures: (click for full size)

Notes

• This was in my 2000 EVC -- it appears as if the glue simply stopped adhering to the aluminum brace.
• I re-glued it with some silicone sealant.