Death Wobble (1 Viewer)

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Ok I have an 86 fj60. Tires are about 3 years old they are 31's. Front brakes were done several years ago with new pads and rotors. Well a month ago I went on a 3 hour trip with a 4x8 trailer to pick up another 40 body. Well on the way there my 60 shook very violently..thought it was the trailer that caused it..happened 2 more times on the trip even after the trailer was loaded. Well it happened even after I drove with no trailer. Well I took it to Walmart where I bought the tires from and got them balanced and rotated for free. The guy said that all 4 tires were way out but he got them balanced. Told me one of my wheels was bent(I know when it happened...hit a huge bump wheeling it) But he balanced it out. I'm not sure where he put the bent tire. The balance was done about 2 weeks ago. Well today I was driving down the road, hit a bump that went across the entire road and when the tires went over and "landed" it threw if off and the death wobble was back. Feels like a really fast tetter totter in the front. I mean it shakes the whole truck, the tranny shifter you can see movin back and forth. Very hard to keep control of it have to bring it to almost a complete stop to get it under control. Gonna jack it up tomorrow and see if I have any slop in the wheels. I don't think I had a bearing go bad, but I could be wrong. Anyone else had this problem? What did you do? What was the cause? Thanks, Chuck
 
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Jul 13, 2003
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Yes, others have had this problem. It's called "death wobble." A search will bring up more info, but what I remember is that this can be caused by loose/worn parts in the front suspension: wheel bearings, knuckle bearings, knuckle studs, tie rod ends, etc.

You are right to jack up the front and start looking for loose stuff. Bet you find something! Post back with what you find.
 

60wag

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A friend of mine recently had a death wobble problem. It was on an 85 4runner that recently had a crossover/high steer conversion. It has brand new tie rod and drag link ends. The wheel and knuckle bearings appeared to be properly adjusted. The one thing we found to be noticeably out was the toe adjustment, (new tie rod.) We improved it a best as we could with a tape measure. That seems to have fixed it. BTW he's running some pretty crappy tires. They are mismatched, worn, 33x12.5 bias ply Swampers. From reading other posts on death wobble, it seems that tire balance is a common theme. If you have a bent rim or two, I'd replace them and balance again.
 
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Oct 12, 2004
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Please correct me if I'm wrong guys, but isn't the death wobble a classic result of a dead steering damper, especially if the wobble is initiated by hitting a bump in the road with both wheels at the same time? Just a thought. Cheers.
 
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Pluton said:
Please correct me if I'm wrong guys, but isn't the death wobble a classic result of a dead steering damper, especially if the wobble is initiated by hitting a bump in the road with both wheels at the same time? Just a thought. Cheers.
I'm not sure - sounds reasonable though. In any case, I still think the problem requires checking to see if anything is loose. This is a free step, and anything loose in the front has got to be fixed. Also as noted above, toe needs to be right. As you point out though, all of this could be on spec, and you'd still need a damper.
 

60wag

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Pluton said:
Please correct me if I'm wrong guys, but isn't the death wobble a classic result of a dead steering damper, especially if the wobble is initiated by hitting a bump in the road with both wheels at the same time? Just a thought. Cheers.

I'll have to disagree with this one. The steering should be stable with the steering dampner removed. If the steering goes into oscillation when it hits a bump or a certain speed it is unstable and needs something corrected to make it stable. The dampener is merely added to reduce abrupt direction changes when driving on poor roads/off road conditions. A dampener may tend to mask a wobble condition but should not be used in an attmpt to fix it. IMO
 
Joined
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Ok did some checking

OK well I took off both front wheels and checked some things out and I think I found the culprit. Good thing is I don't have any slop or wobble so my knuckles are good and my steering arm is good. But I do have a dent in my passenger tire which I took off and put the spare on. And the other which absolutely baffles me. If this has happened to anyone else please let me know. It's been a year since I have wheeled my 60. There is a space between my spring pack and the bottom plate for the ubolts...I have no idea how it happened because the ubolts are tight and I put them on 5 years ago with an impact wrench and handtightened them after. What are your recommendations, can I just loosen the ubolts, reset the axle and tighten them down again. or should I go get new ubolts . Anything else I need to do besides get an alignment once all is in place.

Thanks Chuck

Tryin to figure out how to make my pictures smaller KB then I'll be able to post them.
 

60wag

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If the nuts still turn on the ubolt threads, you can just tighten them. If the nuts are really tight or seized on the threads, replace the ubolts. Give the ubolts a good visual exam though. Make sure they aren't cracked or deformed. You might also retorque the other side as well.
 
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CruisinTiger said:
OK well I took off both front wheels and checked some things out and I think I found the culprit. Good thing is I don't have any slop or wobble so my knuckles are good and my steering arm is good. But I do have a dent in my passenger tire which I took off and put the spare on. And the other which absolutely baffles me. If this has happened to anyone else please let me know. It's been a year since I have wheeled my 60. There is a space between my spring pack and the bottom plate for the ubolts...I have no idea how it happened because the ubolts are tight and I put them on 5 years ago with an impact wrench and handtightened them after. What are your recommendations, can I just loosen the ubolts, reset the axle and tighten them down again. or should I go get new ubolts . Anything else I need to do besides get an alignment once all is in place.

Thanks Chuck

Tryin to figure out how to make my pictures smaller KB then I'll be able to post them.
Some tires have "dents" in them-my BFG ATs did on my 85 4Skinner. Is it really a "dent" in your tire and not your wheel? I would say this is a manufacture imperfection if its really your tire-check your rear two-same dent?

Also, how large of a gap? You may want to check to see that the spring pack pin is seated in its hole on the axle plate before going to torque TOO much.

And for the wobble-it could be anyting w/ the front from tie-rod ends to king pin bearing pre-load. If all is tight and to spec in the steering knuckle-I'd check alignment.
 
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CruisinTiger said:
Tryin to figure out how to make my pictures smaller KB then I'll be able to post them.
Download a free software called Irfan. Works great to shrink pics.

The gap you have is wierd...would really like to see pics...
 
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yeah fj80 the pin is not seated in the whole...which is what baffles the heck out of me. I have no idea how it could of happened. So my idea is to take the ubolts off, slide the axle back forward so the pin will seat in the bottom plate and then put on new ubolts. Very odd situation...I'm headed out of town today so once I get there I'll dl that program and try to get those pics up. Thanks guys
 
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The easiest way to resise pictures is w/ MS Paint. Yes it is an arcaic program but it works and everyone has it. just open the picture and then click "Image" then "stretch/skew" and adjust to whatever size you want.
 
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My bro has an automatic picture re-sizer program on-line for 1h8mud photos-I'll PM him to get on here and give a link or uplaod to mud.

But I use paint for now too. It is archaeic as said-but you can save to just about any format.
 
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Coronado, CA
 
I experienced the same thing a while back and it wasn't until I replaced all my tires that the death wobble went away. I had no problems with any of my steering components and I had a hard time believing that tires could cause such a problem, but it has been 10K miles since I changed tires and haven't had one single problem.
 
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Pearland, TX
 
 
 
CruisinTiger said:
cool cause I'm on a mac so I don't have mspaint
Well then you've one-upped us all here anyway...

I hate my OS-just got the wife an Ibook-love it!

Back to the death wobble.
 
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Sep 6, 2002
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looks like your wheel is dented, not the tire.
and the U bolts are lose. probably a good diea to get new ones.
J
 
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As stated above re-set center spring pin and tighten-but ONLY AFTER checking to see that your springs are facing the same direction DS and PS. There are differences in bush eye to center pin on either side of each spring.

Catching on now that I see your tire sits a bit further back on one side. It may also be the reason your center pin is not seating correctly as too great of an angle in the FR axle.

THIS would definitely cause what you are talking about. Not necessarily sure that new U-bolts are the ticket...unless they are rusted and threading is nasty hard after making sure direction of springs are equal DS and PS.

:cheers:

P.S. Dunno if a good shop can get rid of that wheel dent. Look around at the local scrap yards for an LC. Or new or used-maybe from cruiserparts.net for used.

though they are out on the east coast so alot of the parts have succumb to cancer :frown:
 

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