Hey all,

New to the forum. Recently purchased a 01 XJ and love it. However, over the past couple of weeks there's been a rattling noise coming from the back of the car. It doesn't do it all the time...just on/off. It sounds like it's above the gas tank, right behind the rear seat in the middle of the jeep. It only does it when I'm stopped or parked. I've gotten underneath but can't locate the noise. It's really loud inside. The exhaust hangers are solid and nothing is rubbing against the exhaust pipe. I've searched the internet and a bunch of forums, but I can't figure out what it could be. Any ideas? Fuel pump possibly? I really don't want to drop the gas tank unless I have too.

Thanks in advance for your help.

Chet

 

Tranny mounts.

 

Check your CAT the sheet metal shield on mine came loose and rattled a bit from the inboard side. I pre-drilled and used self tappers. good luck have fun.

 

I checked the cat already, but I'll double check it and the tranny mount. Unfortunately, I'll have to live the noise until next week due to a hectic schedule.

Thanks for the input. I'll follow up once I figure it out.

 

Any luck finding the rattle? I have a 2001 with the same issue.

 

check the jack hold down bracket under the back seat mine made the same noise i finaly found that the bracket was loose

 

I think I had the same rattle winter last year...

It only happens when it's cold out, when the Jeep's only been running for a few minutes (goes away after about 20min or so), and when I'm stopped, but in drive (goes away in neutral and park).

I never got around to tracking it down, and when summer came along I kind've forgot about it. It's coming back with the colder weather though - my guess is the heat shield above the muffler, but I'm not sure.

*edit*

Kind've a difficult sound to describe, too... Rattle is how I would put it as well, but it's a dull, thudding rattle... The sound is almost like someone in another part of the building is cutting through pressboard with a sawzall...

 

another thing to check out....
if you have a hitch on your jeep, check to see if anything in the reciever is loose.
i have a step bar mounted in the reciever, and it rattles like crazy unless i use a wood shim in it.
took me a long time to figure it out.

packages of wood shims are about $1.50 from home depot!

 

I ended up taking it to my mechanic who said it was a bad exhaust hanger/strap, which I had previously checked. None of them vibrated or touched anything so I'm confused by it all. I checked under the jeep afterwards and couldn't locate the new one, but the vibration/noise is gone. It was $50, but I'm not complaining....I'm just glad it's fixed.

 

I have the same noise in my 93
the hanger bracket is the last one that has a "strap" flat piece that goes up between the tank and the frame, it will look solid but the bushing gets hot and wears out, the pipe will bounce up and down when you start / turn off the engine and sometimes going up a hill.

 

Thats whats causing my rattling sound...I'm just too lazy to fix it right now

 

check the engine mounts and the transfer case/transmission mount that might be it, it might create tenssion because it is not moving but the tranmission is in use.