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Unread 12-23-2004, 12:41 AM   #16
Swamp Boy
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I would imagine that the drop pitman for the Xj would work.. I dont know ..
I havent gotten to the point where I need one yet.. I have 5.5 " of lift and I am running stock steering .. No problems .. And all my DW issues are gone..

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Unread 12-30-2005, 06:29 PM   #17
Phil Gerard
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Here's some posts from Kevin Fell of Kevin's Off Road and Jerry Bransford, Mod JF on DW: (they're taken out of context but they have great value)

Let's talk about Death Wobble for a moment: it's the oscillation that happens when your front end components are not in near perfect alignment and are "fighting each other" or reacting to each other. Typically, you'll hit a bump with the right tire first, then the left one directly afterward (often a seam in the pavement) that will start the oscillation until you slow down to under a speed that the sine wave collapses. (Physicists: please correct my terminology if I'm using the terms incorrectly). Now, EVERY single component in the steering that is "tight" (or working in correct phase) and dampens/reduces the propogation of the sine wave is good. If things are out of phase and reacting to each other's movements, then the sine wave begins when the right/left bump combo happens during your commute. ANY COMPONENT that dampens this sine wave is helpful, so things like checking for tire over-inflation (Think about an underinflated soccer ball versus an overinflated basketball when you bounce it), replacing your steering dampener, checking rubber bushings, making sure you have a solid connection between the axle and frame (read: track bar and it's respective polyurethane and steel mounts), and correct toe-in are all things that will reduce the propogation of that sine wave.

As Jerry mentioned above, there is generally not ONE cure for DW...it's just a matter of finding the component(s) that's are putting forces on other component(s) and creating that "equal and opposite reaction" until you begin full-on Death Wobble. I've found that at stock height ZJ/WJ, 6* of caster works well, but you can run as little as 0* and still not have DW. I've found that with a larger tire contact patch (with the pavement) you have to reduce the toe-in measurement. A minuscule amount less than perfectly parallel is what we've found to be best. In my experience, 1/4" is too much, as the tires begin to "trip" over each other (visualize walking pigeon-toed). The stock ZJ calls for 3/16", and if you're dialing OUT the toe-in with a larger tire/pavement contact patch, 1/4" is the wrong direction. I'm not suggesting that every Jeep is the same...it's MOST CERTAINLY NOT...so find your own "perfect" setting by trial and error, write it down on a piece of tape inside the glovebox, and return to that setting each and every time.

It would be difficult to share with you how all of the components work and how adjustments of each item changes the ride characteristics, but bear in mind my previous statement: ANY component that reduces the action/reaction process will benefit you. This includes the poor little steering stabilizer, which people accuse of masking DW. Truly, it doesn't "mask" it...it was designed to keep the destructive sine wave from beginning, and if it's working correctly and all the other components are working happily with each other, then the chance for DW is highly reduced. For additional boring reading on this subject, there is a write-up here: http://www.kevinsoffroad.com/techarticles.html.

Happy DW-free Motoring,
Kevin
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7 degrees of Caster angle is ideal but installing a suspension lift reduces that angle due to how the control arms rotate the front axle after a lift is installed. But you can't just return the amount of caster back to 7 degrees after installing a suspension lift because that produces excessive pinion angle where the u-joint connects it to the front driveshaft. And pinion angle takes precedence over Caster angle... definitely.

You can only achieve the ideal 7 degrees of caster angle after a suspension lift installation without causing excessive pinion angle by repositioning the knuckles. This involves cutting their welds and rotating them to give the desired 7 degrees and then re-welding them in their new position. However, any caster angle over about 5 to 5.5 degrees is fine, you only need "enough" caster angle and 5 to 5.5 degrees of Caster angle is more than adequate for your amount of lift height.

For the Death Wobble problem, 99% of the time it is caused by a combination of things. Most commonly, that combination is a tire being out of balance combined with the trackbar being too loose... usually its lower mounting bolt has loosened. The out of balance tire triggers the beginning of DW and the too-loose trackbar allows the DW to fully develop.

Even if loose enough to allow Death Wobble to develop, the trackbar will not usually feel loose if you just grab it with your hands so it's going to take a torque wrench to assure you that it is tight enough. My Wrangler's lower trackbar mounting bolt is torqued to 55 ft-lbs. and I would imagine yours should be too. If it's tight, your trackbar bushings might be bad but I would first check to make sure its lower mounting bolt is tight. Then get the front tires perfectly balanced. The taller the lift, the more critical perfect tire balance becomes with this kind of suspension.

Finally, make sure your toe-in is set properly. I set my own to 1/8", and you can do this on your own by following the easy instructions at http://www.4x4xplor.com/alignment.html.

So ignore your Caster angle and concentrate on a probably too-loose trackbar combined with a tire that is probably not perfectly balanced, together with insuring the toe-in is set properly.

I had SEVERE Death Wobble 7-8 years ago but since setting my Jeep up as described, DW hasn't reared its ugly head. Good luck and relax, Death Wobble IS curable.
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Unread 02-26-2007, 08:57 PM   #18
LEO_WRANGLER
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An Honest Newbie Question...

Where is the trackbar? Could someone post a pic please?
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Unread 02-26-2007, 09:10 PM   #19
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Holy ancient post, Batman! You have Blaine and Phil both stating that they want to do "intermediate lifts" Blaine is talking about a BB!!! I thought they were joking around when I started reading

Anyway, here's a good link with nice pictures. Basically the tracbar connects the axle to the unibody.

http://www.kevinsoffroad.com/tbconversion.html

Edit: I must say, it's refreshing to see a Newbie searching through the forum. A nice change of pace Welcome!
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Unread 04-25-2007, 06:55 PM   #20
Mooman
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This is the first time I have ever seen "Death Wobble" discussed. I truly thought that up until last week when it happend to me, it was just some odd thing no one had heard of before.

About 5 years ago, my fathers 84 chevy 1 ton dump developed this problem literally over night. The truck had never been crashed, the frame was checked repeatedly for true, and yet with the right bump always on the passenger side, you were instantly on the ole bucking bronco!
In an attempt to cure this, he ended up replacing the steering box, pitman arm, draglink, tie rod and ends, kingpins, axle shafts, axle u-joints, swaybar, steering stabilizer(s), tires, rims, leaf springs, bushings, etc. Everything we could think of. Guess what, never got rid of it. Adding an aftermarket dual steering stabilizer kit helped a little but definately did not get rid of it. He eventually sold it!

So, that was the last I heard of it. Then last week, my GC did it on a rather bumpy road that I normally don't travel. I know that I will be replacing everything when I put a lift in so I am not worried but wow, did that bring back memories. Thanks for the confidence and great topic.
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Unread 04-25-2007, 07:11 PM   #21
QuadraTokn
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Quote:
Originally Posted by LEO_WRANGLER
An Honest Newbie Question...

Where is the trackbar? Could someone post a pic please?
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Unread 04-25-2007, 09:01 PM   #22
gunthagunth
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Quote:
Originally Posted by jdpaysnoe
If that does not cure the problem then I would IMMEDIATELY go to an Offroad Equipment shop. Walk into the shop and point at your vehicle and say Death Wobble. If they start laughing and know exactly what you mean then you are at the right place if they look confused and don't have a clue then you are in the wrong place.
Super old thread but a good one. I remember searching and coming across this. Probably the funniest step in diagnosing DW .
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Unread 05-19-2007, 05:43 PM   #23
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Sorry if this fix was in a link that I missed but this could help someone out too. The wife’s, stock a rock, ’96 ZJ developed the DW, too. After the steering stabilizer and gear box didn’t fix it I finally found the problem. The over the axle pipe was loose as a goose and would lean over an rest on the rear sway bar causing it to lock up. Almost any kind of little bump could set off the gyrations until as a test I just drilled a hole where the intermediate pipe an tailpipe came together (the clamp wasn’t holding), put in a set screw to hold them at the right angle and all was fine. A new exhaust system came shortly after that for the permanent cure.
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Unread 05-19-2007, 05:45 PM   #24
SouthernboyWJ
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nice comments blaine......that sure is a big 2" BB you got on there....haha
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Unread 05-19-2007, 06:29 PM   #25
gunthagunth
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Quote:
Originally Posted by Gramps
Sorry if this fix was in a link that I missed but this could help someone out too. The wife’s, stock a rock, ’96 ZJ developed the DW, too. After the steering stabilizer and gear box didn’t fix it I finally found the problem. The over the axle pipe was loose as a goose and would lean over an rest on the rear sway bar causing it to lock up. Almost any kind of little bump could set off the gyrations until as a test I just drilled a hole where the intermediate pipe an tailpipe came together (the clamp wasn’t holding), put in a set screw to hold them at the right angle and all was fine. A new exhaust system came shortly after that for the permanent cure.
So your DW came from the exhaust hitting the rear antisway? First time I heard of that one.
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Unread 05-19-2007, 09:34 PM   #26
sandman
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no death wobble is related with front suspension only.
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Unread 05-19-2007, 09:38 PM   #27
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how do u adjust caster on a WJ?
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Unread 05-19-2007, 09:43 PM   #28
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One problem I see with this post is the original poster is Dyslexic and has his left and right hubs mixed up.
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Unread 05-19-2007, 09:44 PM   #29
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Quote:
Originally Posted by Packy
how do u adjust caster on a WJ?
tie rod ends.
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Unread 05-19-2007, 09:49 PM   #30
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Quote:
Originally Posted by sandman
tie rod ends.
wait what.. Tie rod ends are for toe aint it. The guy at the place I went too said theres no caster or camber adjustments on the WJ. Was he wrong?
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