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Another Death Wobble

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the74bronco

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Look for egg shaped track bar bolt holes where the bolt has worn the hole oval shaped. When this happens, new bolts and bushing don't help you. It causes death wobble that new bushings don't cure.
No egg shape, but it wasn’t torqued to spec. When I tried to torque it, I bottomed the nut on the non-threaded part of the bolt and didn’t realize it and stripped the threads. I think the new bolt and a couple washers should fix it up.
 
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the74bronco

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I would personally prefer a lock nut, over a regular one with thread locker.
And pants you can always drill a hole of your own through a bolt. If you have a castle/castellated type nut.

Nothing wrong with that idea. Personally though, I would wait until you are certain that you have the axle centered in the frame, while at ride height. Once there you should have no reason to adjust it again any time soon. So a little thread locker there are certainly wouldn’t hurt.
I will use a lock nut. I may drill the bolt one I find where the cotter pin would be.

Should I adjust when the weight is off and then drive a little and measure? What is the best way to center? My jam nut was scary loose. I think that may be part of the death wobble issue.
 

DirtDonk

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Not really. But it certainly wasn’t helping anything.
Allowing the upper eye to twist during suspension movement removes all stresses from the components, but it also adds wear and tear on the threads. So best to keep it locked down.

Never ever adjust anything in the suspension or steering until the full weight of the vehicle is on the suspension and the tires are on the ground.
Nothing will ever be adjusted correctly, until the suspension is sitting at right height.
You sometimes do experience a little suspension settling, but less often in the front than the rear.
And what little settling there is can then be adjusted, if even needed.
But if you adjust it while still in the air, you literally guarantee yourself a readjustment right away.

A few different ways of checking the axle position. Will let some of the others chime in to see what they suggest.
 

DirtDonk

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Because you are tie-rod-over now, most tie rods will hit the trackbar bolt. So yes, a riser is a good idea.
And no, I would not change out the upper mount until you determine that you need it. The angle appears to need both at this point.

Paul
 

66 Bronco Dave

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ksagis

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@the74bronco

Assuming you got the parts on and dialed in, how did things end up on the death wobble? Let us know if we can help on anything.
 
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the74bronco

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@the74bronco

Assuming you got the parts on and dialed in, how did things end up on the death wobble? Let us know if we can help on anything.
Sorry for the massive hiatus. Life got in my way. Spent the last two months getting the lower track bar bolt cut out and the riser bracket installed. Got everything torqued down and realigned. I still have death wobble. Not sure where to go at this point. My track bar seems very locked down. My death wobble hasn’t improved in the slightest. I’m going to check the ball joints and preload over Easter. The shop is telling me to put a stabilizer on it. https://flic.kr/p/2s4LAvN
 

DirtDonk

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Here’s where I pop back in with my oft repeated (almost a mantra really) phrase that “it’s the tires“ or words to that effect.
You either have one or more bad tires (internal defect), or your toe-in is out of whack for that particular tire.
That tire model is kind of known for incurring Death Wobble. But even in those cases, it’s usually a result of a bad tire and not just the tread design itself. Otherwise they’d all do it!

I will reread this discussion, but at any point during all this discovery, have you rotated the tires to different positions to see if it changes the wobble characteristics?
Have you played with air pressure?
Have you verified toe-in for yours and not just on an alignment rack using degrees?
Sorry if we already covered that, but I didn’t want to lose what I was typing by going back over the previous pages.
 
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the74bronco

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Here’s where I pop back in with my oft repeated (almost a mantra really) phrase that “it’s the tires“ or words to that effect.
You either have one or more bad tires (internal defect), or your toe-in is out of whack for that particular tire.
That tire model is kind of known for incurring Death Wobble. But even in those cases, it’s usually a result of a bad tire and not just the tread design itself. Otherwise they’d all do it!

I will reread this discussion, but at any point during all this discovery, have you rotated the tires to different positions to see if it changes the wobble characteristics?
Have you played with air pressure?
Have you verified toe-in for yours and not just on an alignment rack using degrees?
Sorry if we already covered that, but I didn’t want to lose what I was typing by going back over the previous pages.
I really appreciate the insight. I did rotate the tires a few tire. I didn’t notice a change. I have had two different sets of tires but both were on the same wheels. I just had it aligned to 0.5 degrees this morning. It was at 2 degrees after the new steering kit. Pressure I have had up to 35lbs, but now I am running 25lbs. I am beginning to believe they might need to get swapped anyway.

What are your thoughts on:

1. Adding a heim end to the track bar to eliminate the bushing.
2. With the trac bar riser bracket, should I go to a stock pitman arm or remove the frame drop to be in better alignment.
3. Ball joint issues?
 

ksagis

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This might be chasing ghosts but I think the drag link to tie rod geometry is wrong. Aren’t the flanges on the tie rod to drag link supposed to to be more “vertical”? If not, it rolls on you.

Edit: adding stabilizer is a red herring imo
 
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the74bronco

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This might be chasing ghosts but I think the drag link to tie rod geometry is wrong. Aren’t the flanges on the tie rod to drag link supposed to to be more “vertical”? If not, it rolls on you.

Edit: adding stabilizer is a red herring imo
I had it vertical initially, but it made contact with the track bar riser bracket. I guess it is common to turn it. Since my death wobble was the same with the factory steering linkage and this setup, I’m guessing the issue lies elsewhere.
 

Oldtimer

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What condition are the bushings, at the frame end of radius arms?
Are rear axle u-bolts and spring shackle bolts all tight?
 
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the74bronco

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What condition are the bushings, at the frame end of radius arms?
Are rear axle u-bolts and spring shackle bolts all tight?
The rear leafs and shackles have been replaced and are tight. I replaced the radius arm bushings when I did the front springs in the last two years. Them look good an tight.
 

ksagis

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I had it vertical initially, but it made contact with the track bar riser bracket. I guess it is common to turn it. Since my death wobble was the same with the factory steering linkage and this setup, I’m guessing the issue lies elsewhere.
I’d look for input from others on this but comparing factory geometry to your current setup does make some sense but 37” tires are a lot of leverage to excite badness.

Did rig always have death wobble (or at least when you owned it)? When did it first show up?

One last thing, I seem to recall that you fixed the movement at the top track bar connection (and now have new trackbar). Can you remind us what was done to fix it?
 
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