Can dropped pitman arms prevent death wobble?

You are creative, I'll give you that. Is that like micro vibrations that the MC bushings eliminate and micro aggressions we all exhibit towards the disenfranchised?

Or is it more like Jumbo Shrimp? Wait, wait, I got it, it's like the track bar lever arm, right?
No, it's just categorizing Death Wobble as triggered by a constant cause with otherwise tight parts (like your wife's low tire you once mentioned) or dormant with loose/worn parts that's triggered by a bump or whatever...if you think about , I'm right. I realize it can be soooo much more , but that's a good starting point for a layman...by a layman.

And so I used the wrong term for how the track bar works, I was also right that the worn upper right bushing mount can act essentially the same as a loose or worn track bar. Same net effect.
 
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No, it's just categorizing Death Wobble as triggered by a constant cause with otherwise tight parts (like your wife's low tire you once mentioned) or dormant with loose/worn parts that's triggered by a bump or whatever...if you think about , I'm right. I realize it can be soooo much more , but that's a good starting point for a layman...by a layman.

And so I used the wrong term for how the track bar works, I was also right that the worn upper right bushing mount can act essentially the same as a loose for worn track bar. Same net effect.
Dormant and passive, awesome.
 
Dormant and passive, awesome.
I also call it DWWTH- death wobble waiting to happen. This doesn't cover all the bases and the weird wild stuff, but it helped me grasp a little of it.
 
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Only way the pitman would be to blame is if it was not tightened and walking on the sector splines or the rod end is slopping in the taper.
 
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Now that I think about it, I think one of the rear tires was a bit out of balance before I rotated. However the DW also started happening before the rotation. I’ll definitely look into getting them balanced.

I was going to suggest un-rotating your tires and see what happens. Now that I read this I'll say un-rotate your tires before you get them balanced and see what happens. Why before? Mainly because the TJ front suspension prefers almost perfect balanced tires and too many guys out there just get them close enough for grandma's sedan to feel OK on the way to church or the store and if that happens to whatever tires you end up putting up front you could end up with the same problem (DW) for the same reason (balance) but end up looking for something else to fix it.
 
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I also call it DWWTH- death wobble waiting to happen. This doesn't cover all the bases and the weird wild stuff, but it helped me grasp a little of it.
I think I get what you’re saying. And yes, the death wobble I’m experiencing is only triggered by a big bump in the road.
 
I think I get what you’re saying. And yes, the death wobble I’m experiencing is only triggered by a big bump in the road.
Perhaps, but consider this for a moment. If there is accuracy contained in the DWWTH statement, then every single TJ on the road is afflicted with it. ;)
 
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Perhaps, but consider this for a moment. If there is accuracy contained in the DWWTH statement, then every single TJ on the road is afflicted with it. ;)
There usually is if things are worn or loose. Really all coil spring track bar vehicles are candidates..check out any Dodge or F250 forum.

This is exactly why I break it into 2 categories...if it's bump activated look closer at the front end than the tires. If it can't recover tracking from a bump something is allowing it to do that.

..if it happens at a certain speed every time that's typically tires causing it.

Then again, my f 250 had a track bar allowing it , but it wouldn't reveal itself until 78 mph...what set it off at that speed .

This isn't any revelation..just a way of viewing it that works in my head...and may appear very limited based on someone with as much experience as you. I know I have a lot of blind spots and much to learn.
 
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Mr. Andy, et al. If you want to get a handle on what we are dealing with, it helps to have a smattering of knowledge about precession and angular momentum. Even better are fewer words and more visual. This video shows what happens when you try to change the direction of two small gyroscopes that are first spinning the same direction, then spinning the opposite direction. At the conclusion of the second example, it becomes patently obvious that the perfect way to solve DW is to have one front tire spin the opposite direction. I shall forever refer to this as PPDWS or passively perfect death wobble solution.

 
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I'm no expert and barely remember precession from having to figure out compasses while flying but this works for me... passive devices like track bars, shocks, etc. cannot be the root cause of DW since they generate no energy to power the DW. But a spinning tire that's not perfectly balanced generates a lot of energy which to me is the root cause of DW. Loose components like the track bar can allow the DW to occur more easily but you need an energy source (the out of balance tire) to power the huge monstrous shaking and vibration that is DW.

Think of a spinning well balanced motor sitting on your work bench. It barely, if at all, needs to be bolted to the work bench. Smooth! But put an imbalance onto that spinning motor and you'd need some mighty strong bolts etc. to even keep it on the work bench since it could vibrate the bejesus out of itself and the work bench. But when the motor is perfectly balanced? It doesn't take much to keep it sitting on the work bench while it's spinning.

So to me, DW is most commonly a combination of things... an imperfectly balanced front tire coupled with something that is loose. The more perfectly the front tires are balanced, the less you need to worry about everything being tight. The less well balanced the front tires are, the more loose components become an issue.

Am I guaranteeing the 100% accuracy of my theory? Nope but it has worked for me. The very worst DW I ever experienced was when my '97 TJ was still less than a year or two old with the factory suspension. Somehow a front tire's balancing weight came off and it caused an OMG help me JESUS life-passing-before-my-eyes DW experience. I had no idea what had happened, I had not yet even heard of DW. As it started it felt like a front-tire balance problem before it turned into full-blown DW so on a hunch I took it in to have its tires balanced. The tech said a front tire had lost its balancing weight(s?) and rebalanced it for me. No more DW ever on that TJ for the rest of the time I owned it, I just made sure to keep the tires rotated and balanced. I had a few developing DW cases on my present TJ which turned out to be a combination of a front tire out of balance coupled with a front track bar bolt that wasn't tight enough. Balancing the tires and tightening the snot out of the track bar bolt cured it.

Last comment... not all tire shops will take the time to balance big tires like ours perfectly. They only get them to what they consider to be "good enough" which for a big tire on a TJ is never good enough. You have to convince the shop to spend the time to get them 'PERFECT'. Sometimes a promised $10-20 tip to the tire jock doing the balance if they come out perfect is enough to do the trick.
 
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It’s generally either bad tires, loose crap or some of both. How’s that?
 
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It’s generally either bad tires, loose crap or some of both. How’s that?
It is the inability of the locating components to prevent precession in the spinning assemblies.

I have produced DW on a rig with everything tight and perfect including tire balance.
I have produced DW on a rig that had so much slop in the front end that when I removed it, DW occurred.

In other words, there is not a pat answer. The system needs to be diagnosed and then the faulty components replaced when found.

I have seen terrible tires not cause it and perfectly balanced tires cause it. I put the perfectly balanced tires on the rig with DW and they came off of a rig without as a test.
 
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Last comment... not all tire shops will take the time to balance big tires like ours perfectly. They only get them to what they consider to be "good enough" which for a big tire on a TJ is never good enough. You have to convince the shop to spend the time to get them 'PERFECT'. Sometimes a promised $10-20 tip to the tire jock doing the balance if they come out perfect is enough to do the trick.

The sad part is that getting it right usually only takes one maybe two extra spins of a tire. You should not have to bribe them into doing quality work. It can also help to find a shop with newer machines that can measure wheel straightness as well. I helped a local repair shop here that was struggling to find the cause of DW on a JK. Turns out it had a cracked AEV wheel. You can balance a bent wheel (or driveshaft for that matter) on older machines as they think it is just imbalance.
 
It is the inability of the locating components to prevent precession in the spinning assemblies.

I have produced DW on a rig with everything tight and perfect including tire balance.
I have produced DW on a rig that had so much slop in the front end that when I removed it, DW occurred.

In other words, there is not a pat answer. The system needs to be diagnosed and then the faulty components replaced when found.

I have seen terrible tires not cause it and perfectly balanced tires cause it. I put the perfectly balanced tires on the rig with DW and they came off of a rig without as a test.
I follow you. I know you have seen a lot of scenarios and understand way more about the forces at play.
 
Well, I have found the culprit. I don't know how I missed it in the first place! The front track bar has an awful lot of play in it. At least 1/4" vertical movement frame-side and over 1/8" lateral movement axle-side. Now I'm in the middle of researching JKS vs Currie vs Metalcloak adjustable trackbars.

What should I go with, considering front Dana 44 (stock cover), stock control arms, and 3" of suspension lift?