What's Death Wobble Like? A Strange Thing Happened To Me Today...

[gogmorgo]

I've looked it up and as far as I can tell it's essentially a side-to-side vibration/oscillation? Mostly when I search I get discussions about the cause, but not much about what it actually is.

But that's not what I think happened if I understand it correctly.

It snowed a bit today, so traffic was of course retarded, but I was still having trouble getting off the line, even with the new tires, so I got about 200 lbs of softener salt and threw it in the bed, now it's much better, but I digress.

Then on my way home, I merged onto an elevated freeway, of course into the traffic crawling at 40mph in a 60, with the left lane's traffic moving at a normal speed. I went to accelerate into a gap, and when the tranny kicked down, it almost felt like I got rear ended on the passenger side, except I didn't... it felt almost like the front passenger side lifted, sort of the way it does when I accelerate, except much more violently and the driver side didn't feel like it lifted at all. It was a bit like really serious diagonal ditch-twisting, tbh. The result was the whole truck rotating, and then fishtailing as I corrected, and I got it under control after about three direction changes, foot off the throttle, and then it was as if nothing had happened. I lost maybe 5mph, everything seems normal, and I couldn't reproduce it. But I didn't try that hard. I looked underneath, and didn't find anything broken or loose front or rear

 

Any thoughts? I was in 2wd at the time, although had been using 4H to get moving a few times prior.

possible causes that I can think of are:

Mechanical failure of some kind, even though I couldn't find anything and everything seems normal. But I didn't get the wheels off the ground.

Uneven traction, but I'm not sure that I could have hooked up as hard as I did, and my experience is that I just would've spun the other wheel. AFAIK I don't have any kind of lsd or locker.

Freak gust of wind. (It was still blowing pretty hard)

I actually did get rear-ended and didn't notice and there's no damage to the truck and everyone else on the road completely ignored it. (they gave me serious space but didn't actually stop)

 

I don't think it's death wobble, since it started with the kick-in-the-pants, and as far as I can tell death wobble is just a wobble. Correct me if I'm wrong?

[Eagle]

You lost traction and fishtailed. Good job catching it before it became a complete spin-out, but in slippery conditions what you do NOT do (not ever) is punch it into passing gear. You drive like there's a raw egg (in its shell) between your right foot and the accelerator peddle.

 

To answer your question about death wobble: It feels like a demented djini has grabbed hold of the front end of your vehicle and is doing his best to fling it and you off the road into the nearest ditch. It is absolutely uncontrollable, and the only way to stop the insane dance the front wheels are doing is to slow down to very nearly a complete stop. It is called "death wobble" because it feels like you ARE going to die ... right then and there.

[Pete M]

is it possible you hit something in the road?

[Comanche County]

If you get DW, you'll know it. Like Eagle said, it will feel vibrate so bad you'll think the truck will fly apart or lose the front axle.

 

Just had some of it myself due to a loose track bar bushing.

[gogmorgo]

The road was pretty much clear, and I didn't really punch it, at least I don't think I was trying to. Usually I try to do the raw egg thing, but I get impatient sometimes... But definitely not doing that again. Really don't need to scrub sh*t out of my seat.

If I did hit something, the guy in front of me didn't. Especially after what Eagle said, I'm thinking it was a loss of traction. And now I'm embarrassed for bringing it up. It didn't really feel like when you swing the rear end out going around a corner, it felt more like the entire truck had been grabbed and dragged to the left, that's why I was worried.

 

But thanks everyone.

[87MJTIM]

My vote: U-joints.

 

Just my $0.02 (that's US, not CA) ;)

[Eagle]

The road was pretty much clear, ... It didn't really feel like when you swing the rear end out going around a corner, it felt more like the entire truck had been grabbed and dragged to the left, that's why I was worried.

 

There's a difference between "clear and "pretty much clear." If there was a line of snow between the two worn-down tire tracks in either lane (or a row of snow between the two lanes, it was probably slushy, wet, and heavy. As you switched lanes, running a tire into that line of slush is like slamming on the brakes -- on one wheel. The heavy, mushy snaow grabs the wheel and makes the front end try to slew around.

[gogmorgo]

Pretty much clear in this context meant snow blowing across the road, but nothing really sticking to it. This wasn't the wet heavy snow, it's the dry arctic-like snow that's pretty much just ice crystals. Doesn't stick together or to anything, except where it packs into drifts. And it really doesn't stick to an elevated road at 10F in that kind of wind. I feel I should add I've been driving in snow since I learned to drive, which was in the winter, just for personal validation. I've been a crazy teenager in the snow (maybe still am a bit) but this was unlike anything else I've ever experienced. I've hit drifts up to three feet deep with one/both front wheels (er, the whole front end), slewed around in loose/wet/mushy snow, basically been a hoonigan. Admittedly never in this particular truck, but this was not like anything I've ever experienced. The only way it makes sense as a loss of traction is if right before the transmission kicked down I was on some slipperier bit, and then hit clear, dry pavement with the spinning rear right tire suddenly hooking up with the torque from the downshift, pretty much launching the truck over. It really did feel like something slammed into the rear right corner, just without the whiplash. The change of direction was so violent, it's what made me think of what I'd heard of death wobble. But still, there's no way that happened because of loose snow between the lanes or even ruts. I hadn't even moved towards the other lane yet, since there was still a car going past at that point. I was accelerating so I could slot in behind it.

But I know better than to try that again, for the safety of myself and others on the road, and I thank God that nothing happened that time.

 

My vote: U-joints.

 

Just my $0.02 (that's US, not CA) ;)

This actually sounds very plausible too. The u-joints were redone last fall when the PO had the truck inspected (i've got the receipts), but I've been getting a clunk from the front right corner when I hit some bumps. I'd just attributed it to the unsecured battery bouncing around, since the PO said he took it to a mechanic who couldn't reproduce it, and I'm pretty sure they should last longer than 8k miles. I was actually driving back from picking up a strap for the battery to eliminate that possibility.

[Comanche County]

Do you have a locker or LS in your rear axle? Maybe a slippage situation then a downshift and lock up at the same time?

[gogmorgo]

Afaik it's an open diff, but I don't really know. The only thing I'm going on there is that the PO didn't mention anything. I have been wondering though. Only way to check without pulling the cover is to pick up the back end and give her a spin, right?

[xjrev10]

If you get DW, you'll know it. Like Eagle said, it will feel vibrate so bad you'll think the truck will fly apart or lose the front axle.

 

Just had some of it myself due to a loose track bar bushing.

 

You WILL know death wobble. Yer life will flash in front of yer eyes till you stop. It can be exciting when its expected and terrifying when its not!

[JFAComanche6]

My MJ sat in a field 8 years prior to me gettting it, so the suspension was fubar from the start. You'll most likely feel your heart drop to your @$$the and firmly apply the brake when you get the good 'ol death wobble.

[NewKindOfClown]

I used to wonder if I was getting DW when I got some bump steer after lifting my XJ. When I actually did get DW, there wasn't an ounce of doubt in my mind. If you know what DW is in concept, it's unmistakable when it happens. For what it's worth, mine was caused by a loose axle-side trackbar bolt.

[xjrev10]

I used to wonder if I was getting DW when I got some bump steer after lifting my XJ. When I actually did get DW, there wasn't an ounce of doubt in my mind. If you know what DW is in concept, it's unmistakable when it happens. For what it's worth, mine was caused by a loose axle-side trackbar bolt.

 

In my experience its always been a issue with the track bar. Had it in a 89 XJ, 00 XJ, and a 88 MJ. Axle side bushing or wollowed out mounting hole for the track bar on the axle.

[Pete M]

Just for clarification, it's not just the track bar. plenty of people have had bad track bars and never had the Death. but a bad trackbar can be the proverbial straw that, if fixed, might push the sloppiness factor back under the DW thresh hold and make the it go away.

[xjrev10]

Just for clarification, it's not just the track bar. plenty of people have had bad track bars and never had the Death. but a bad trackbar can be the proverbial straw that, if fixed, might push the sloppiness factor back under the DW thresh hold and make the it go away.

Quoted for truth. There are hundreds of threads about DW and probably 20 things under the front of a Jeep that could cause it. Sometimes you just get lucky and the first part you change happens to be the problem part!