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The Adam Blaster
October 23rd, 2006, 19:31
The last week or so i've been getting a low-pitched hum in conjunction with a very slight vibration from the back half of the Jeep.
Seems to only happen when i'm on the gas. But, i don't have to be accelerating, just keeping a constant speed will make the noise.

As soon as i let totally off the gas, the noise stops.

Any ideas what i should be checking? Easy things first please. :D
Slo-Sho
October 23rd, 2006, 20:13
OOh OOh! U-Joint!


:idea:
The Adam Blaster
October 24th, 2006, 08:41
I was thinking u-joint, but in the past when those have gone on the d-shaft, i'll get a bit of clunking when i shift from my forward gears to my reverse gear. (Automatic tranny)
AlohaBra
October 24th, 2006, 20:40
OOh OOh! U-Joint!


:idea: Do you have a lift kit? Does it happen at 35 MPH (sorry USA here)? Year of the XJ..?
The Adam Blaster
October 24th, 2006, 21:15
It's a '98 and the noise happens from the point of initial acceleration.
I do have a lift (3") kit on it, as well as 31" BFG M/T's.

I haven't checked if the noise occurs at 35 or greater speed, but i'll try that tomorrow.
The Adam Blaster
June 13th, 2007, 05:35
Little update on this:

It ended up that the rear carrier and gears were a little chewed up. I ended up getting some work done and had a Detroit installed back there. :D
jeeperjohn
June 13th, 2007, 10:48
So you got a hummer in the back of your XJ? NICE!!
jfiscus
June 13th, 2007, 12:41
Little update on this:

It ended up that the rear carrier and gears were a little chewed up. I ended up getting some work done and had a Detroit installed back there. :D

I just saw this post & was gonna say your bearings are shot in your rear end. But, it looks like you already found this out. I got an XJ with the same problems, I'm replacing the rear end.