Horrible noise. Sounds like a really loud (and poorly running) diesel truck guts, low pitched. The guy who had my jeep before me said he just changed the exhaust, if that helps any. Tomorrow I'll try to figure out where the rattle comes from, but I'm pretty sure its the cat./exhaust area.

It's been doing this for awhile, as long as I've had it, 3 months.

88 4.0L 6 cyl

 

Very common to have the exhaust pipe contact the trans/t-case crossmember where it travels above it. Many times the cause is bad engine and trans mounts.

 

Could also be the flexplate bolts are a bit loose?

 

I had a similar noise, mine was the exhaust tip vibrating on the rear spring/shackle

 

My vote is also on the T-case/tranny mount.

Made a world of difference on rear rattling when I changed mine.

 

yah it will rattle on the cross member ive had my muffler replaced and i get that rattle