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Death Wobble Northridge Bolt Kit

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Old 05-26-2012, 05:53 PM
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While parked on hard pavement, suggest having someone turn the steering wheel back and forth about 1/2 turn while you watch the track bar bolts, etc. for any lost motion.
Old 05-26-2012, 06:02 PM
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Try rotating your tires and see if you get it 20-25 mph.


Originally Posted by Wgrin
I actually put the bolts on while the jeep was on the ground initially. The only thing I can think is that the track bar holes may have been wallowed out already. I did not change the bolts on the rear track bar, they put a relocation bracket on that when I had the lift put in and I was having trouble getting those off. But I don't think the rear track bar would be the problem as when I get the DW it starts as soon as the front tires hit something. I can get a new adjustable track bar that is by Superlift for 144. My DW lucky only occurs at around 20-25 mph, Ive even gotten it stop by speeding up a couple times.
Old 05-26-2012, 07:40 PM
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I measured tonight on my axle, and noticed my driver side is 1/2" further out than my passenger side. I'm going to try the track bar and have them adjust the axle to center
Old 05-26-2012, 09:08 PM
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Read Planmans thread on death wobble and shimmy before spending anymore money.
Old 05-26-2012, 10:08 PM
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Ditto on planmans checklist. I've never had DW, but no sense in tossing away your hard earned money without knowing what the real culprit is
Old 05-27-2012, 03:17 AM
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Originally Posted by GunDude
Try rotating your tires and see if you get it 20-25 mph.
If you have everything torqued correctly, X2 on trying a tire rotation before buying more parts. Not an expert, but if your shimmy is happening in a certain mph range without hitting any bumps it may not be death wobble ? Sounds like a bent rim or a tire out of balance.
Old 05-27-2012, 05:23 AM
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Originally Posted by Wgrin
I actually put the bolts on while the jeep was on the ground initially. The only thing I can think is that the track bar holes may have been wallowed out already. I did not change the bolts on the rear track bar, they put a relocation bracket on that when I had the lift put in and I was having trouble getting those off. But I don't think the rear track bar would be the problem as when I get the DW it starts as soon as the front tires hit something. I can get a new adjustable track bar that is by Superlift for 144. My DW lucky only occurs at around 20-25 mph, Ive even gotten it stop by speeding up a couple times.
This may sound super picky but it will help isolate your problem a little bit. By making the statement that you can get the wobble to go away if you speed up sometimes you just also made the statement without knowing it probably that you dont actually have death wobble then. True death wobble is when you have too little trail in your system and cannot overcome an unbalanced steering input that is greater then the rotation force of the wheel. Put more simply if you can speed up and it goes away it means you dont have death wobble. The only way to stop real death wobble is to come to a stop, and real death wobble becomes more violent as it continues until your system is maxed out.

Given this information we can rule out a few problem areas right away. It is not your caster angle on your LCAs so you can leave those alone, it is also not your SS. As others have mentioned backing everything off and a torque to spec is never a bad idea.

I would however place a bet on your wheels/tires being unbalanced. You noted the MPH of the wobble at 20-25mph that is the speed in which unbalance vs rotation for is at its highest really before rotational force starts to take over. At super slow speed say rock crawling on a trail at 5mph or less you are never going to feel if a tire is unbalanced or not because you are going so slow. At 50mp as long as side to side balance is ok the rotational force on the tire will smooth out much of the unbalance and most shocks will dampen the vibration pretty decent. The speed area most prone to an unbalanced tire is that 20-25mph area because the tire is moving fast enough for it to be felt but not fast enough to have enough force to start to dampen the unbalance. You mention also that it starts when you hit something like a bump etc. This also would support the idea because your tire would be slightly off a vertical axis and would amplify the unbalance.

I would pull the wheels off and inspect the wheels and tires. Check for lost weights, tire chunking, compacted dirt/mud in the treads, bent rim, etc. It doesnt take too much to throw off the balance on big heavy mud tires. If you dont see anything wrong I would go have them checked for balance or even better what I use is balance beads exactly for this reason. Balance beads provide dynamic balancing that will compensate for all those above mention things without the need to babysit your tires.

Either way good luck finding your issue
Old 05-27-2012, 11:24 AM
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Originally Posted by dognights

This may sound super picky but it will help isolate your problem a little bit. By making the statement that you can get the wobble to go away if you speed up sometimes you just also made the statement without knowing it probably that you dont actually have death wobble then. True death wobble is when you have too little trail in your system and cannot overcome an unbalanced steering input that is greater then the rotation force of the wheel. Put more simply if you can speed up and it goes away it means you dont have death wobble. The only way to stop real death wobble is to come to a stop, and real death wobble becomes more violent as it continues until your system is maxed out.

Given this information we can rule out a few problem areas right away. It is not your caster angle on your LCAs so you can leave those alone, it is also not your SS. As others have mentioned backing everything off and a torque to spec is never a bad idea.

I would however place a bet on your wheels/tires being unbalanced. You noted the MPH of the wobble at 20-25mph that is the speed in which unbalance vs rotation for is at its highest really before rotational force starts to take over. At super slow speed say rock crawling on a trail at 5mph or less you are never going to feel if a tire is unbalanced or not because you are going so slow. At 50mp as long as side to side balance is ok the rotational force on the tire will smooth out much of the unbalance and most shocks will dampen the vibration pretty decent. The speed area most prone to an unbalanced tire is that 20-25mph area because the tire is moving fast enough for it to be felt but not fast enough to have enough force to start to dampen the unbalance. You mention also that it starts when you hit something like a bump etc. This also would support the idea because your tire would be slightly off a vertical axis and would amplify the unbalance.

I would pull the wheels off and inspect the wheels and tires. Check for lost weights, tire chunking, compacted dirt/mud in the treads, bent rim, etc. It doesnt take too much to throw off the balance on big heavy mud tires. If you dont see anything wrong I would go have them checked for balance or even better what I use is balance beads exactly for this reason. Balance beads provide dynamic balancing that will compensate for all those above mention things without the need to babysit your tires.

Either way good luck finding your issue
Well there has been shimmys that I can control and then there has been Violent DW where I can't do anything but stop.
What about the axle being uncentered? I already have purchased a new track bar but I'll retorque too
Old 05-27-2012, 11:51 AM
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Originally Posted by Wgrin
What about the axle being uncentered?
When my jeep was hit in the axle the idiot service manager tried to say that my axle was fine because from the factory they are 1/2 to an inch off center to the drivers side. Except after the hit it was 3 inches off center so to me it sounds like your axle is about right.
Old 05-27-2012, 11:53 AM
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Originally Posted by Wgrin
Well there has been shimmys that I can control and then there has been Violent DW where I can't do anything but stop.
What about the axle being uncentered? I already have purchased a new track bar but I'll retorque too
My axles were uncentered to the passenger side by 1/2", but my Jeep never incurred any wobbles because of it. I think Planman's DW thread is your best bet. This is how my tires looked uncentered...and it still drove fine even like that.



Last edited by Runewolf1973; 05-27-2012 at 11:58 AM.


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