A weird thumping noise has been occuring in my 4R. Seems like its coming from the rear undercarriage, and I only hear it when I go over a large bump or low dip with a person or two in the back seat. I thought it might be the spare tire being loose and hitting the bottom, but its really secure, so that rules the spare out. I also thought it might be my sub box, but it's quite heavy and doesn't slide at all. My dad told me it might be the bump stops in the rear, but my spring rate feels the same and with people in the back seat, it doesn't sag all that much. Anyone know what I'm dealing with?

 

Yes you are probably dealing with your spare tire as thought of Although it feels nice and secure it can slide. This is a common complaint

 

It's east to eliminate the tire as a possible problem, take it out and go for a drive. Could also be something loose, or worn shocks.

 

Ditto, mine does the same thing.....annoyning but I just live with it.
I would also take the spare out and just verify that is actually the issue.

 

Not much to go on, but I would guess a bad, worn or loose shock. I had a similar noise at the front driver's side wheel and it went away after replacement of the shocks.

 

I have a coulple of thumps also. Mine is the rear seat, where it latches up. Fold down the rear seats and take for a test drive. I havent figured out a way to stop mine. I also haven't taken enough time to assess the situation yet. I'm thinking of splitting some hose and wrapping the attachment points. I just have to spent some time with it.

 

My jack under the rear seat used to thump around a little. Took me forever to figure out it was that until somebody here mensioned it. I thought it was part of my rear suspension too. I just extended my jack once it was in place to make it sit in there a bit better, and no more thumps!