Intense death wobble

[75sv1]

No, your not exaggerating!! Some of the times that is what I am experiencing. Its much worse when there is a Semi on your back. I will say, some times it is not in the steering wheel. Other times it is. I'll wait till I get a cooler weekend. I might have the thing realigned by another shop. I am not running a steering stabilizer. I did order one last week.

[DirtyComanche]

14 hours ago, Eagle said:

If your life isn't replaying before your eyes while you pray you can stop before the truck is thrown violently off the road -- it isn't death wobble.

 

No, I am not exaggerating.

 

100% accurate.

[75sv1]

I found one of the U-joints on the front drive shaft loose. I took off the front drive shaft. It drove better. Still, some DW, or whatever you want to call it. It seemed to be the u-joint was still in good shape. The straps might be the problem. I have seen some U-caps, that I might try. I also plan to put on a steering stabilizer shock.

[JeepSchmidt O'Guinness]

On 7/15/2018 at 10:55 PM, Eagle said:

.... you're sure you're going to die, like RIGHT NOW!

.....

No, I am not exaggerating.

Brought me right back. Can still feel the resonation in the wrists.

[Eagle]

1 hour ago, 75sv1 said:

I found one of the U-joints on the front drive shaft loose. I took off the front drive shaft. It drove better. Still, some DW, or whatever you want to call it. It seemed to be the u-joint was still in good shape. The straps might be the problem. I have seen some U-caps, that I might try. I also plan to put on a steering stabilizer shock.

 

I don't like to beat a dead horse, but we use words to communicate, so it's important that words are used to mean the same thing to everyone. The term "death wobble" has a specific meaning -- it refers to when BOTH front wheels are shaking so violently that it's almost impossible to control the vehicle, and the only way to stop it from shaking is to slow down to 5 MPH or less, or stop completely. If that's not what you are experiencing, you are not encountering death wobble and should not be asking advice to cure death wobble. It's not "DW, or whatever you want to call it." Either it's death wobble, or it's something else.

 

If you can keep driving with the shaking, or speed up or slow down just a little bit and it goes away, you don't have death wobble.

 

We're all here to help one another but it's difficult to diagnose problems remotely by Internet forum. When the wrong terms are used to describe tghe problem, it's impossible.

 

[/rant mode]

[AZJeff]

For those of you who have never experienced death wobble, or are not sure what is actually LOOKS like from the outside, there are some videos out there showing the shocking behavior.

 

Here is a good one:  

 

 

[SVPete]

^^Um yeah. That's what death wobble means to me.

[75sv1]

From the inside, mines worse than the video. Way worse. Sorry, at highway speeds, I'm not getting out and looking. Its very weird, sometimes its a big pothole etc. The other day it was more of a wave in the road. It drove on Monday probably 1 hour each way on the highway. No, real problems. Tuesday, I had 3-4 episodes.

       I did ask a neighbor(s). Jeep guy, deal mechanic. His was a busted steering box mount. I'll torque the steering box bolts. I am suspecting motor mounts. It gave me an excuse to order Brown Dogs. I did put in an after market trans mount. Unfortunately it was a bit higher  than the stock mount. That and a 2-row radiator and aftermarket clutch fan, I had a hole in my radiator. I do have a MOPAR clutch fan coming.

[AZJeff]

Motor mounds and transmission mounts have nothing to do with death wobble.    In fact, bad motor mounts can be diagnosed really easily with the vehicle sitting still and having a helper "load" the engine with the transmission in gear (and the parking brake or service brake applied FIRMLY).

 

While the helper is doing this, you are examining the motor mounts for severe distortion of the cross bolt in the rubber.  It should move some, but NOT to the point where it reaches the outer part of the mount.

 

I suspect you still have a front suspension issue if you are experiencing TRUE death wobble.   Your description of a pothole or a "wave in the road" triggering the behavior is CLASSIC death wobble symptoms.

[DirtyComanche]

Normally motor mounts look torn when they're done anyways.

 

But yes, your problems are suspension related, front suspension related...   You can get horrible sway/hopping from the rear shocks being blown out, especially if SOA, but that's a different matter.

[carolinajeepman]

Not sure where you live, but if you are somewhere in the US that is subject to excessive rust, you may want to check the frame where the steering box bolts down. On my 97 XJ, we spent $$ replacing parts only to find that the frame had cracked where the steering box bolts down. Iron rock makes a steering box reinforcement that I welded on and it fixed my death wobble. Just a thought...

 

[DirtyComanche]

Just now, carolinajeepman said:

Not sure where you live, but if you are somewhere in the US that is subject to excessive rust, you may want to check the frame where the steering box bolts down. On my 97 XJ, we spent $$ replacing parts only to find that the frame had cracked where the steering box bolts down. Iron rock makes a steering box reinforcement that I welded on and it fixed my death wobble. Just a thought...

 

 

That will happen without rust, and I think I mentioned it?  Not sure.  The bolts can come loose too, which will give you as much trouble.

[75sv1]

I do have an upgraded Steering box spacer. Also, I put on a Logan's bumper. It has extended attachment plates. I will check the torque on the bolts. Yes, bunch of stuff to check. I'll look at the shocks. My thought on the motor mounts is more of a reaction or resultant. It starts out with DW, then there is a large mass flopping around. I am getting a banging sound. It is less with the front driveshaft removed. I plan to upgrade to the 'U' bolts on the u-joints, instead of the straps.

[gogmorgo]

With wheels and tires, and all the suspension components, the front axle is going to be getting pretty close to the same weight as the engine, so you're correct as far as there's a large mass moving around. 

Banging sound definitely means something's loose; although it could just be exhaust or something else trivial. But I'd be looking really close at control arm bushings, track bar/mount, and all steering linkage. Get a helper to wiggle the steering wheel back and forth while you check each joint for play. Also make sure the springs are in the right place, I've seen more than one case of the bottom coil snapping off at the retainer, and having the spring kick out and jam itself against the C on the axle.

Do you only hear the bang, or can you feel it in your feet? Can a passenger? Might help track it down. 

[Eagle]

4 hours ago, 75sv1 said:

I do have an upgraded Steering box spacer. Also, I put on a Logan's bumper. It has extended attachment plates. I will check the torque on the bolts. Yes, bunch of stuff to check. I'll look at the shocks. My thought on the motor mounts is more of a reaction or resultant. It starts out with DW, then there is a large mass flopping around. I am getting a banging sound. It is less with the front driveshaft removed. I plan to upgrade to the 'U' bolts on the u-joints, instead of the straps.

 

Your description makes it sound like you can continue driving with whatever shaking or banging you are encountering. If you can keep driving, you do not have death wobble.

 

As someone has already commented, motor mounts are unrelated to death wobble. So is driveshaft. Death wobble is the result of a harmonic between the two front wheels. Each shake of one wheel is transmitted to and reinforces the shaking of the opposite wheel, so the shaking continues to increase in amplitude and violence unless/until you stop (or slow down to less than about 5 MPH).

[75sv1]

My symptoms vary. Sometimes it works itself out. Other times, I do have to stop. It might happen on a large pothole or not. Other times it is a mere wave in the road.