Well, just replaced the track bar, lower ball joints and front axle u-joints. So far the death wobble is gone, the front end is no longer squeaking and grinding (sounded like a model t bumping down the road) and the popping is gone too. The Jeep drives like new and I'm very happy with the outcome; the u-joints were clearly binding, which led to the majority of popping and grinding. I think next weeks project will be to change a worn motor mount; couldn't hear it vibrating until all the other stuff up front was fixed. Sometime next week I guess.

 

Does that mean the transfer case will be be noisey as well with the tires lifted? There was definitely a noise coming from the TC that coincided with the shaking and it was not really the noise that I heard with the tires down.

 

This death wobble, is that where the front end shakes and shimmeys when you hit a good bump? I get a good wobble every now and then but there is one spot on an exit ramp into Richmond that every time I hit it it feels like someone picked up the front of my truck and moved it over a foot suddenly.

 

does the steering wheel move side to side quickly and violently when that happens

 

No, the front end just shimmeys.

 

sounds like it could be bad tie rod ends or bad ball joints or bad wheel bearings

 

Be advised I read that with the front driveshaft removed it will allow dust into the axle and tcase. May cause damage.

 

When the jeep shakes like that, there's a whole lot of noise under there. By the way, there are still noises under there when it's not shaking. Some noises are hard to diagnose. That's why many professionals will jokingly tell you to turn up the radio. Anyway, as you probably know, there are normal and abnormal noises. Of the abnormal noises, there are benign noises that you just let progress until they get worse or failure occurs if it ever will. And there are bad noises that need immediate attention and that are relatively easy to find. You may have to let this one progress until it becomes obvious to the technician where it's coming from.

Correct me if I'm wrong. You get a noise on left turns like a bad CV joint on front wheel drive vehicles. You also hear a grinding noise that sounds like a right front wheel bearing (a hub assembly in Cherokees). A u-joint will be heard moving slowly while it is placed under a bind in hard turns (e.g., a parking maneuver). A wheel bearing is louder at speed when it is loaded in even slight turns. Does it make the noise when moving slowly as well as at speed? Can you make the noise at speed when you turn slightly left and stop the noise when you turn back slightly to the right (i.e., weaving in your lane back and forth)?

I think removing the front driveshaft would be a good idea if it doesn't cause a grinding as you try to put it in gear. Give it a shot. Remember to mark the yokes so that you can reinstall the driveshaft in it's original position. You mentioned that the t-case seems to be working properly, but I admit that it could still make noise. Also change the t-case fluid if it hasn't be done within the past year. Drain the fluid into a clean pan and examine it for large and abundant metal flakes or chunks of material.

I believe that because the front output shaft and pinion shaft will still be in place, the seals will keep dust out of the transfer case and front axle respectively.

 

During a death wobble, the entire front shakes violently. I think the issue on the exit ramp is called bump steer, where the wheels steer on a jounce without input from the steering wheel.

 

Untrue, with the front DS removed, the axle and tcase still have the yokes there.

 

No, is the answer to the last 2 questions above. If I had to guess what it most likely SOUNDED like (with my limited knowledge), I would say a u-joint. But all the u-joints feel solid and firm when I try to shake them by hand. Is that not a sufficient test of a u-joint? I have had a bad wheel bearing before (in a mid sized car) and I feel like this is not anything like that. This noise only occurs on load, such as pulling off from a stop or powering up a hill at slow speed (was much worse when I loaded it down with camping gear last weekend). It now occurs while steering straight ahead sometimes (again, only on pulling off) and can be eleviated by steering just slightly to the right (when possible of course). Cruising on the highway, I no longer hear the noise. Also the noise I experienced before with a wheel bearing issue was more of a constant whine, that increase in pitch and volume with increased speed (and of course turning of the wheel), that is not at all what is going on with the jeep.
Let me ask this, if I take off the front drive shaft, and the problem goes away, have I really diagnosed anything? For example, if it is not my TC, and its the axle u-joints instead, will they still make a noise if they are not connected to a drive shaft. Or what if it is the joints in the drive shaft itself. It seems possible (to me) that removing the driveshaft could easily take care of the noise, and still not know what was actually causing it. I would like to get my 4 wheel drive back at some point (sooner than later).
Also, keep in mind that I have been keeping it in regular 2 wheel drive the whole time (other than to test it out in a parking lot). At what juncture does the 4 wheel drive engage? I am assuming it is in the TC itself. I was told that turning the wheel puts a bind (therefore extra stress) on the TC chain but how can this be so if they are disengaged from one another?!

 

bump

 

your 4wd is engeged through the tcase if you rmove front drive shaft and the niose goes away then its more likely the u jionts on the drive shaft if it continus then it is still possible to be the u jionts in the axle the axles still turn when in 2 or 4wd the wheels on an xj are always locked wich is why there is no manual hub on them so shacking the axles my not reviele a bad ujoint sometimes it can feel tight but still be bad because the way the weight of the jeep is siting may be keeping them from moving

 

your 4wd is engaged through the tcase if you remove front drive shaft and the noise goes away then its more likely the u joints on the drive shaft if it continues then it is still possible to be the u joints in the axle the axles still turn when in 2 or 4wd the wheels on an xj are always locked which is why there is no manual hub on them so shacking the axles my not show a bad u joint sometimes it can feel tight but still be bad because the way the weight of the jeep is siting may be keeping them from moving

 

What is the best way to inspect a u-joint then? Lift the tires and shake them? Is there a visual sign? Am I probably correct in thinking that both places I took it to who suggested a loose TC chain are wrong?
Thanks for all your help btw, you guys are a great resource! A National Treasure, I tell ya!