There is something rattling underneath my Z28. It sounds like it is right underneath the rear seats, maybe down the transmission tunnel. Is there a mount that might be broken somewhere?

 

Well I was thinking heat shield too, but it's a pretty big rattling. Doesn't sound like it's a heat shield. Sounds like it'd be something more solid. I'll probably check it out tomorrow though and see what I can find.

 

Do you have an electric cutout installed under there? I had some rattling there last week and the set screws on the cutout plate had came loose and that was the source of the rattle.

 

My rear sway bar came loose, causing a rattling sound. Couldn't figure out what it was (sounded like a loose exhaust hanger to me), but the shop found the problem, and tightened it up for free.