When It's Death Wobble, Except When It's Not...

[Tim Redman]

Every so often, I see posts in here battling the age-old questions of "is it, or is it not, death wobble?", and how to properly go about fixing it. It's almost gotten to the point where it's become something of a religious crusade by some. Now, I can't offer all (or even most) of the answers, but I can serve up my recent observations, and hopefully this gives a little bit of perspective to the people who are experiencing similar issues, as well as to the people who are trying to help them.

Now, as a person who has tightened the nuts on his front track bar probably not as tightly as he should have, I have experienced the pants-wetting thrill that is DW. However, recently I've had some issues with a couple of tires being out of balance. When they're on the back, things get a little bit loose around 55mph, but to either side of that, the vibration still exists, but attenuated to a certain extent. It seems that, right around that speed and tire size, there's a resonant frequency that seems to give the old girl fits.

I somewhat expected that a balancing issue was the case, so I rotated tires one afternoon. Sure enough, with the bad tires on the front, I was barely able to get it up to 45mph. Now, here's where things start to get fuzzy with some people. At 45, with poorly balanced tires, the vehicle begins to rattle and violently shake, and from somebody who's experienced DW before, it feels EXACTLY how death wobble feels when it starts to kick in. So, it's entirely understandable that some people might jump to the conclusion that this is the problem, despite the other symptoms present.

Keep in mind that there are a couple of things you absolutely can't do during an episode of DW:

• you can't slow down a few MPH to make it go away, and
• you most certainly can't accelerate through it

Now, I absolutely wouldn't recommend speeding up as a diagnostic method in this case, but slowing down is always going to be your best (and generally, only) option. So if you slow down 5 or 10mph and it goes away, have the balance and shape of your tires inspected. If you have to slow down to a near or complete stop to get it to go away, then after you wipe the mess out of your shorts, grab your favorite wrench and socket set, crawl under the front end, and start checking things for security. It's not anywhere close to a hard and fast rule, but the way I do it is start from the middle, and work your way out (track bar -> drag link -> tie rod ends -> ball joints -> axle U-joints, or something along those lines), which, VERY generally speaking, is the order in which things are likely the problem, and a careful methodology helps insure that nothing gets missed in the inspection..

The big thing to understand is that, at the outset, this behavior exhibits just like DW, so it's excusable for that diagnosis to be the first one people jump to. It's important to collect as much information as possible about not just what your Jeep does, but how and when it does it, and for how long.

 

[Chris]

Most people haven’t truly experienced death wobble. They assume that it’s nothing more than a vibration such as the type you feel when you have an unbalanced tire.

If someone has TRULY experienced death wobble, they’ll know it, because it will have scared them shitless when it happened. The same can’t be said for a simple vibration.

Death wobble is also something you can’t accelerate through. A vibration on the other hand will typically come and go at certain speeds.

 

[Tim Redman]

I thought the same thing, but I believe you start to deviate slightly from that when it's more than one tire that's out of balance (or out of round), as was my case**. It's not likely that the high side of each tire is going to be in sync, so you not only get the vibration from the balancing issue, but you get the side to side action of two out-of-balance tires fighting against each other. In my case, it does feel like DW, or at least how DW feels in the first five seconds or so. However, I don't think that the severe vibrations make up 100% of the terrifying aspect of DW; you'd also have to include the fact that it doesn't go away unless you stop, so even decelerating, the vehicle feels completely out of control.

** As an aside, it seems obvious in retrospect that both tires didn't go bad at the same time. At least one was out of balance for a while, but it felt like a simple alignment issue at the time, and what steering wheel vibrations did exist, they were not severe and confined to speeds above 65mph. When the balance went out of the other tire as well, that's when this whole exercise began. Since I had already decided to put new wheels and tires on the Jeep anyway (I found out after an alignment that at least one of the tires was 10-12 years old, almost as old as the Jeep herself), I never bothered getting them rebalanced.

 

[IPerkWVU]

I experienced true deathwobble a few weeks ago coming home from the trail. Was going 70 on the highway and felt like I was going over washboards, a violent shake, held the steering wheel tight and slowly decelerated. The Trackbar jam nut was loose as well as when we installed the trackbar to the axle side, the original flange nut was rusted so a different bolt was used; it allowed a small amount play at that joint (didn't realize until diagnosing on the side of the road). Was traveling with a few Jeeps so we were able to get things tightened up. I bought a new OEM bolt and flange nut from my local dealership and swapped it out. As I removed the bolt that was on at the time, it broke in half.

While different that what your looking into /trying to figure out was no way I could drive through it, it was BAD, had to come to a complete stop.

Sent from my Pixel 2 using Tapatalk

 

[Tim Redman]

There seem to be some issues with certain track bars where the axle-side bolt is not sized correctly for that bushing. It's very difficult to find a proper diameter bolt for some of those applications. Even with a custom solution, sometimes all you can do is torque it down and keep an eye on it. The crazy thing about DW is that it really doesn't take a whole lot of play to cause problems. Regular inspections are never a bad thing, particularly if you off-road a lot.