Added a little lift, death wobble problems! sway bar related?? searched...

Hello.

I did a search on death wobble as I've had this problem in the past on a '92 XJ. added new tires to that one and everything was fine.

My current question is regarding a '00 XJ, Up until yesterday it had been stock with new tires, no problem, It was pulling a little bit to the right so I was going to take it in for an alignment anyways.

We put in 3" springs and 2" shackles, nothing else. My question is...am I ok with just the 3" springs and nothing else up front?(LCA's, etc...)

The only thing we moved was the sway bar and sway bar links which got disconnected since we needed a little bit of extra flex to get the springs in. other than that nothing else was disconnected. There is now DW at about 65-70 MPH with tires I had no problems before and driving back I put on some spares and those DW starting at 45MPH depending on the road(bumps, etc).

The sway bar seems to be pulling harder(more pressure upward as the nut is being untightened) on the right side and the links are very close to the spring(more on the left side than on the right), not upright, but like pointing to the spring, and the pull to the right that was there before is way more noticeable.

I haven't read anything really relating the sway bar and DW, would the sway bar have anything to do with it or can I totally disconnect it and be fine on the freeway?

I'm going to throw on the 31" tires I had on the old '92 that solved the problem and take it in for an alignment, just thought I'd post this before to see if I get any feedback as to what to do regarding the sway bar and sway bar links...or if this would be solved with the alignment.

I'm guessing I got a little under 3" of lift up front since I have a winch and heavy bumper on there too.

any help/comments greatly appreciated.

thanks

I dont think a sway bar would have anythign to do with it... most likely Trac Bar. Get it aligned, tires balanced, and have the Mechanic tighten the crap out of your trac bar while its on the rack.

yeah, your axle is most likely off center throwing off your geometry. I had mine redrilled on the axle side to center the axle. cleared it up for the most part, there is a little shimmy in the steering wheel at 45 though. Best bet is an adjustable one.

steering damper has a lot to do with that to. That was the fix for my dad's '96xj. we had major death wobble towing our boat, so we swapped out tie rods and stuff, and went "oh, the damper's shot... Crap! we could've saved $80!" try that first... if you pull it off and can extend, and compress it without a ton of effort, it's probably shot...

tayman said:

steering damper has a lot to do with that to. That was the fix for my dad's '96xj. we had major death wobble towing our boat, so we swapped out tie rods and stuff, and went "oh, the damper's shot... Crap! we could've saved $80!" try that first... if you pull it off and can extend, and compress it without a ton of effort, it's probably shot...

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The dampener was shot because of the real reason it was DWing. In most cases ur steering stabilizer will be a temporary bandaid and DW one time will kill it dead! Put a steering stabilizer on LAST! Fix the trac bar get an alignment.

tayman said:

steering damper has a lot to do with that to. That was the fix for my dad's '96xj. we had major death wobble towing our boat, so we swapped out tie rods and stuff, and went "oh, the damper's shot... Crap! we could've saved $80!" try that first... if you pull it off and can extend, and compress it without a ton of effort, it's probably shot...

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Steering damper is a band-aid and not a fix. Its never the *cause* of anything.

If you look at the bigger more built rigs out there, many of them don't run steering dampers at all, without deathwobble.

have to agree with Cal here, I have a 3 link with 35's & don't run a dampner or sway bar, no DW at any speed..

You said nothing had changed other than the coils & shackles? Well a lot has changed then....Check your caster setting & it should be between 6-7 deg neg "reward tiping" caster. All your angles have changed, Double check & then re-check everything you did is all I can say..Start with caster as that is the first thing that comes to mind here.

Billy

cal said:

Steering damper is a band-aid and not a fix. Its never the *cause* of anything.

If you look at the bigger more built rigs out there, many of them don't run steering dampers at all, without deathwobble.

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I seriously think that somepeople mistake DW for a lil shimmy in the wheel. DW at 45 Mph still gives me nightmares from time to time. DW at 70 should and could rip the axle out from under the jeep. It's definitly enough to fold a tracbar like a taco.

lowrange2 said:

I seriously think that somepeople mistake DW for a lil shimmy in the wheel. DW at 45 Mph still gives me nightmares from time to time. DW at 70 should and could rip the axle out from under the jeep. It's definitly enough to fold a tracbar like a taco.

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Yeah, no kidding... we had death wobble under breaking at about 45mph, and it scared the crap out of us... the brake rotors were a bit warped too, and that's what we think set it off... his '96 is stock, so it's not likely it has anything to do with the tracbar... I lifted my '90 xj about 3" in the front, and haven't had any problems yet. I do need to re-drill for the tracbar though... but hell, it drives, and wheels just fine!

Your trac bar needs "fixing" You can find out how much lift you have after adding the bumper and winch by measuring the center of the wheel to the bottom edge of the flare. I know there are more capable people who can guide you to exactly where that list of stock heights may be...or search for it.
How much travel are you getting on stock shocks with added 3" springs?

I wanna know how they managed to get 3" springs on the front without d/c the trackbar, shocks, drag link.....ONLY the sway bar.

Plain and simple, you need an adjustable trackbar...i wouldnt do the re-drill method....plus you probably need some new shocks. THEN take it for an alignment as you are probably toed-in quite a bit.

Sway bar has everything to do with it. All the parts work as a system. Did you buy, or make, 3 inch extended mounts for the sway bar system? you really need those, or get some longer links to make up for the lift. The track bar more than likely need about and inch or so in more length.
Important note**** do not install the tracbar until you have everything else conected and the vehicle is on the ground. Then do exactly as Jeep instructs to "center" your setup.
Flex the car up and down..... basically bounce it from the bumper up and down.
then
Push it from a fender left to right a few times, making sure you really move the front end.
Then
Bounce the front again.
all this will center the whole kit and make adjusting the tracbar so easy.
For highway use, the sway bar must be connected. Those of us who dont have them conect and are "fine" are lucky that the system is currently aligned. I called Jeep about this problem and spoke to one of the guys whom designs the suspensions and he laid it our for me, along with telling me what page the instructions were on in my Helms manual.
I thought it was funny but it works perfectly.

Thats BS! The sway bar is not MANDANTORY to drive the vehicle down the highway (Tho I do suggest using it for saftey reasons) and IMO there is no possible way that the sway bar is causeing his DW.

the reason his sway bar is "off" is b/c of the Tracbar not keeping the body centered over the axle.

And what do you mean you "called Jeep" - do they have a 1-800 number?

ZJ coils..... they're the same length as the xj coils, just a hell of a lot beefier... I had to fab some raised shock mounts both front and rear, so I acatually get pretty good articulation. These are my rear mounts... don't have pics of the front yet...

And here's what I did with them yesterday!



Black diamond at Hollister Hills..... I don't use sway bars, city highway, or wheelin' (duh), and it drives perfecly fine!

To say I called "Jeep" Is to say I call the technical assistance number found in the Helms manual for Chrysler, which then leads you through an automated system (which I skipped by asking for the operator) which leads to a tech guy who helps out with tech issues. I got to talking with him, found out he is a fellow Az Cardinals fan (we suck I know), which led to a "hey my boss is retiring, but he used to be one of the main design engineers for that suspension", among other things. I got forwarded to that guy, whom is a very avid XJ fan. Turns out his son went to TCU, which is where I go to school, and we got to talking about the XJ. I learned alot, to say the least. I am not a trained mechanic, so I took his advice to heart. Lo and behold all my death wobble issues that I ever had went away by just making sure the whole "system" is correct. That is the way it is designed to run, not just a smooth control thingy for when I am driving. Taking it off for articulation on the trail is fine, if not reccomended. Diconnecting the sway bar for trail is ok since I cannot recall ever driving my machine over 30 mph up or down a trail, I sure someone out there will refute that and say they have done it lots of times (power to ya).
Back to my point, at highway speeds the self centering design of the suspension over compensates itself causing it to swing back and forth in an effort to get back to "center". The more pieces of the designed system attached restrict the movement, the less you attach the more movement is allowed.
The big reason for the 3" sway bar mount extentions is the same idea for why when you lift the vehicle you need longer control arms. As the bars swoop down they point too far down and cannot control lateral shift as well as they could if they were horizontal. As with the case of the steering going wierd when the lift is to high for the control arms. By dropping the sway bar back to position and connecting them for highway driving, and anything approaching 40mph, the system is then more stable and will not violently shift from side to side.


wow I feel like frank from old school after the debate scene.... where did all that come from?!:viking:

Are you saying that having the wrong sway bar links cause death wobble?


A lot of people run every kind of car, truck whatever without sway bars daily and dont have problems. A sway bar is a good idea, but not always needed and defiantly wont cause DW.

mk153smaw said:

Back to my point, at highway speeds the self centering design of the suspension over compensates itself causing it to swing back and forth in an effort to get back to "center". The more pieces of the designed system attached restrict the movement, the less you attach the more movement is allowed.
The big reason for the 3" sway bar mount extentions is the same idea for why when you lift the vehicle you need longer control arms. As the bars swoop down they point too far down and cannot control lateral shift as well as they could if they were horizontal. As with the case of the steering going wierd when the lift is to high for the control arms. By dropping the sway bar back to position and connecting them for highway driving, and anything approaching 40mph, the system is then more stable and will not violently shift from side to side.

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While the theory here sounds good, practical personal experiance doesn't play along. I'm not saying don't run a swaybar - I think its a good idea to have one connected - but a half decent set of shocks in good condition will do more to prevent DW than the tightest swaybar ever could.

if I'm not mistaken, I believe DW is caused by being out of perfect alignment, or having sloppy bushings, causing stuff to wiggle, then thrash violently... why would not having a sway bar, which prevents... sway... and roll... cause DW? Like I said above, I don't any, and have been fine everywhere up to 80MPH (as fast as I've gone in it...)