2001 XJ 4x4 4.0l question about a noise

This noise only happens when i am moving slow and it is like a small clunking almost like there is a screw stuck in my tire. the noise increases as i accelerate until i get over about 25 mph. It sounds like it is underneath the drivers side floor boards maybe under the engine compartment. My guess is that it is the 4 wheel drive shaft u joint? No sure though. any help would be great.

How many miles and what transmission?

Is the noise quick or slow? Does it speed up as the vehicle speeds up?

it has 4.0L engine with automatic trans. 158000 miles. The noise seeds up as the jeep speeds up then disappears at about 25 mph

thanks

You may be looking at some new Ujoints. Usually it's the rears that go out first. On my 00 Grand Cherokee, same drivetrain, I had to do mine at 135K.

i did the rear drive shaft at about 100000 miles. could they be done already? I just use it as a daily driver and going into the bush when i hunt, no off-roading at all. Could it be the front drive shaft? Does it turn even though the 4wd isn't engaged? thanks

The front does turn even when the transfer case is disconnected.

You said the noise was like a screw in the tire; so I'm thinking it's in sync with tire rotation speed?

ya i think so to so you think probably rear drive shaft or front or both?

Well if it was the driveshaft it would be a quicker noise, like chikachikachika, rather than a slower noise in sync with the tires, whup whup whup. I can't do sound effects by typing. :)

Is it just on the road, or in all conditions?

definitely in sync with the tires....whup, whup whup describes it best and it speeds up as the Xj accelerates.

Is it only on the road, or in all conditions? If it's just on the road, it may be a rotation issue, if you've got some cupping on the tires.


This may be too obvious and you've probably done it, but have you checked your tires for nails, etc?

all conditions and yes i did the tire check for nails...lol, you must know me to suggest that though..lmao

all conditions and yes i did the tire check for nails...lol, you must know me to suggest that though..lmao

Me too....many a time I've been scratching my head and someone comes over, says, "What are you doing, did you know that this thing over here is loose?"...


Is the sound metallic? Reason I ask is that since it's in sync with the tire speed, it's got to be tire related. Metallic would indicate to me a bearing or something similar. I've had branches wrapped around my axle, too and those can make a racket.

How many miles are on the tires? Tread is ok I take it?

tread is great although there is only 1/4 of the tread left. wear pattern is even.

Loose or broken wheel stud? That would make a crunchy noise.

(got to get offline now for a bit)

no loose or broken wheel nut.

ok i figured it out! i jacked it up and the u-joint in both front wheels are toast. surprised they haven't broke yet. thanks for all your help. take care

Good find! I was running out of ideas...always helps to have eyes on the target!

Have a good one --

do you know where i can get some step by step instructions to fix this, maybe even a diagram or 2? thanks for everything

This should help. (http://www.4x4wire.com/tech/axle/ujoint/)

Looks like you'll have to pull the axle to work on it, and that I don't know about, but Google is your friend....

Do you know if the axle will just slide out or do i need to get in to the differential and undo something to get it out? thanks again for all your help!

I'm pretty sure there's a C clip or something similar in the axle. The only one I've been inside of was a 70's Chrysler so I can't say for sure.

...Although after a Google search I came up with this goody:

http://www.jeeptech.com/AxleGeneral.html#cclip

So probably the C clip, and you'll need a special tool.