When I'm driving between 15-70mph (the majority of the time) if I take my foot off the gas and let the engine slow the jeep down I get a funny sound that I can't really put well into words, but I'll try. Its like a rapid metal tapping sound, not from the engine, but seems to be from the transmission area. Maybe even something like a heat shield rattling rapidly but very consistently. I have a manual, and like I said it does it when my foot is off the gas and there is pressure on the drivetrain. If I put the clutch in there is no noise. Any idea of what it could be?

Other info: I also need to replace my ball joints, and recently had the passenger side U joint replaced, but it made the sound before the U joint was replaced... I was kind of hoping that would stop the noise when it needed replaced. It has 94K on it and has not had a clutch replaced. I'm not experiencing any problems with actual shifting or driving, just the noise. It's not loud enough to get a good recording, and if I have the radio on or we are talking you don't really hear it.

 

The thin metal heat shields around the exhaust. They make a vibrating sound if they come loose.

 

X2 on the sound, last jk I think it was the heat shields. I need to crawl and take a look. Let us know if u find anything

 

 

Only when I'm in gear and foot off the gas though???

 

but if the clutch is pressed the noise disappears. could that be a throw out bearing? or clutch plate issues?

 

I hope not, 11000 miles new.

 

Clutch in or out doesn't matter, it doesn't make the noise if it's not in gear. When its in gear it makes the noise.

 

This is cheap and worth a try:

I dont think you mentioned what model/year you have. I have an 07 jku 6 speed.

The exhaust crossover pipe that runs along the tranny support beam.... i had a rattle forever until i wrapped my exhaust with fiberglass heat wrap. You could just try a few hose clamps as tight as you can get them, around the above mentioned exhaust section. It has a flange welded to it that is known to rattle.

If this doesn't stop your rattle, at least you've eliminated it as the source and it only cost a couple bucks.

 

Hey gents,

I am having the same issue... wanted to see if you ever came to a solution or found the source of the noise.

I have a 08 auto with 2.5 lift... 35 tires
Mine started with a growling sound when I let off the gas and then it started with the clanging. I took it out today to see if I could better define the source of the noise.

1. only happens when I get it past 40 mph and let off gas
2. noise stops when I am costing in neutral
3. 1 and 2 apply when in 4H
4. 4L it happens at low speed and even in neutral.