My '04 rubi just got DW so I took it to a mechanic (non-dealer) who said that my U-joints and steering damper are bad and my DW should be gone once I get those fixed. I'm not mechanically inclined in the least, so does this sound like a reasonable claim?
What I understand about the DW is that it has to do a lot with your alignment, and Axel. Also a few other problems under the hood and tires not being fully inflated. I just recently bought my jeep from some idiot and I think I have more than one reason causing DW. My alignment is off, tires are a little low but I haven't bought anything to check psi yet, and I do have a leak which is causing the steering wheel to be turned a quarter way. If your that concerned, check with another auto shop unless you already paid this place to check everything out.
Theres a sticky on death wobble. Most common causes seem to be tires not balanced or track bar. Steering stabilizer will only mask the problem. Have someone move your wheel back and forth while you look for slop on the track bar. Good luck.
They could be bad, but I don't think they cause death wobble. You can easily check the u-joints. Slide under the vehicle and grab the drive shaft. Turn it by hand and watch the u-joints. If they are bad they will have slop in them. The yoke won't move as much as the shaft. Or yu can let up on the gas releasing pressure on the shaft while going down the road and the shaft will vibrate bad with worn u-joints. Nothing to do with steering.
Not sure what lift or size tires you are running but seems the 2 most common cures are alignment (I had DW and got 3 alignments before curing the problem, set my caster at 5.75 positive degrees) and trac bar (bushing gets worn out, have someone sit in the jeep and move the steering wheel back and forth from 10-2, if you see the bolt moving in the frame you could probably use a new one). I have a 4" suspension lift on 33's on my 05 LJ. Good luck and hope this helps.
If it's the brake rotors you'd know. Just get up to around 60mph on a smooth road and get on the brakes fairly hard if it starts shaking and continues to shake after you let off the brake it's probably not your rotors. Alignment, and trac bar is usually the cheapest place to start if it's not under warranty. Do one at a time though or you'll never know what fixed the problem when you get it corrected.
It sounds to me like the shop is trying to take you for a ride. Warped rotors like go51green said you would know about right away when you hit the brakes, but rotors can be turned rather than replaced. As for u-joints causing death wobble that mechanic is up in the night. You can easily check if they really need replacing by following neverfastenough1's post. Check the track bar and see the sticky on the death wobble. I would stay away from that shop though and find one that does Jeeps on a routine basis as he does not seem to know what he is talking about.
2000 Sahara, 3.5" Rubicon Express Lift, 1" spring spacer & 1" Body Lift, 33" or 35" BFG Mud tires, Front & Rear ARB, Rancho 9000 shocks, UCF Ultra High Belly Up
I was going over the tracks around 45 mph and the car began violently shaking, along with the steering wheel, until I came to a stop.
I don't have warranty on the Jeep so I'm worried a dealership would be extremely expensive. This mechanic is asking $600 though...
Does alignment alone cause DW?
Ok, your "violently shaking" remark confirms it was true Death Wobble.
First, a new or stronger steering stabilzer (dampener) is NEVER even part of the fix for DW. Calling that part of the cure for DW is like calling a band-aid part of the cure for a skin cancer. The Jeep should be able to operate without a steering stabilizer without it developing DW.
DW can be caused by a multitude of problems or a combination of smaller problems. Most commonly it is triggered first by something... a bump in the road (or railroad tracks) or an out of balance tire. Then once triggered, something has to be loose for the front-end to allow the DW to actually fully develop. Typically that can be a loose passenger-side trackbar mount, bad ball joints, etc.
What I would do is stop going to that mechanic because he doesn't know, really, what he is doing where DW is concerned after reading what you said he told you to do.
Instead, I'd start looking for what is loose... with the wheels on the ground, have a helper start the engine and then start turning the steering wheel repeatedly back & forth while you lay down in front and start closely examining every single part of the front and checking for unwanted side-to-side movement. Especially at where the passenger-side track bar bolts to the axle, ball joints, etc.
Make sure too that you don't have too much toe-in which can encourage DW. I'd also make sure the tires are perfectly (!) balanced since the bigger tires a TJ runs can have a big effect on the front end and even trigger DW when they're not perfectly balanced.
Gone wheeling, back late sunday... Remember that having a different opinion doesn't also require one to be a jerk when expressing it.