Bad wobble between 45-55 mph.. Need help!! (long)

[Talyn]

The length is exactly what I'm talking about. At that hieght just over 3", also you have the spacers, I'm not saying they are bad, but when your axle isn't centered over the spring mounts may be causing your wooble. I know when I was at 3" adding longer LCA's made my XJ more stable. You have done a really good analysis, I'm thinking either there was an accident or your at the point for LCA's. Your caster will change, if your worried get UCA's to boot. Go to the classifieds for cheap used stuff.

So you are saying that the extra 1/4" of an inch (by removing spacers from behind the LCAs) or so the aftermarket LCAs will give may help? I have the caster turned up by adding spacers behind the LCA brackets. If I put in aftermarket LCAs I will be keeping the caster the same because if I put my caster any higher my pinion will have issues with the angle on the drive shaft. The only way I would be to push the axle forward anymore would be to get aftermarket UCAs... but all the tables I have seen regarding UCA length at a certain lift height have shown it to be very small over stock measurement.. like 1/8" small.


If I had just paid to get my '91 XJ fixed from the accident.. ugh

-Chris

 

[ChuckD]

I know, but your not left with much else. I agree, you have the LP D30. You'll need the Aftermarket UCA's to balance out caster and DS angle. Can you take pictures of your springs with your tires off. Maybe we can help you out there.

 

[RCP Phx]

I have very seldom have found DW or hints of it to be just 1 item.Your switching tires/vehicles really shows this.It is a combination of things allowing movements that I attribute wobbles of any kind to.For me it has usually been trackbar/control arm issues(Ive had it on all four of mine).I highly recommend the RE Extreme Duty trackbar/bracket as something to think about(I got the wobbles on mine at 3000miles@3"+ and a Rusty's trackbar)!Not after that nor since have I even had a hint of wobbles. Now with my long arms I am still running less than 3* of castor with no problem!

 

[MudDawg]

Have you had your tires checked for true????

Recently I had an alignment and tire rotation done...that caused a minor wobble or "shimmy" at the same speeds...45 to 55 mph..the balance was checked and the tires individually spun up to 80 mph...no sign of vibration...the balance was fine...BUT when they were checked for true or roundness...one was out of round...trued both tires and rebalanced...drives like new now...

 

[Hawaiian Style]

I have exactly the same problem but mine seems to act up only at 50-55 MPH with the worst of it a 55. I've swapped my AT's and MT's with no real change. Wobble gets agrivated after hitting a bump. The really strange thing is that it happens most of the time, but not all of the time. Been the same way for the 3 years I've owned my XJ both pre and post lift. I can see the front driver's side tire moving when it gets bad... not good, in fact pretty scarey. 3 shops have been unable to find any problem with it.

 

[Rudy]

As dumb as this sounds, when I finally replaced my worn out and over stretched Pro-comp shocks with new Skyjacker shocks with urethane bushings, my wierd 45 to 55 mph wobble went away. I swear thats all I replaced. Good Luck.

 

[Talyn]

As dumb as this sounds, when I finally replaced my worn out and over stretched Pro-comp shocks with new Skyjacker shocks with urethane bushings, my wierd 45 to 55 mph wobble went away. I swear thats all I replaced. Good Luck.

What was your wobble like? Wa sit there even over smooth pavement with out bumps?

-Chris

 

[Rudy]

Just going down the road, like clockwork at 45mph till about 55mph on smooth pavemant. You could watch the steering wheel start to move back and forth. Nothing violent just a steady wobble and then after 55mph it would go away. I could go 80 without a problem. I replaced tre's, got an R.E. heavy duty track bar and new lower control arm bushings (Rustys), rebalanced the tires to no avail. Thats not to say it's what your problem is , but it worked for me. I just replaced the shocks cause I needed to and that turned out to be the problem, I guess. Good luck and God bless.

 

[Talyn]

Just going down the road, like clockwork at 45mph till about 55mph on smooth pavemant. You could watch the steering wheel start to move back and forth. Nothing violent just a steady wobble and then after 55mph it would go away. I could go 80 without a problem. I replaced tre's, got an R.E. heavy duty track bar and new lower control arm bushings (Rustys), rebalanced the tires to no avail. Thats not to say it's what your problem is , but it worked for me. I just replaced the shocks cause I needed to and that turned out to be the problem, I guess. Good luck and God bless.

Yes, that is so similar to my problem... I never thought it was teh shocks because it happened even over smooth pavement. So, it looks like it is either the shocks or the LCAs.

Anyone have a part number for Bilsteins for a 3.25" lift?

BTW I will be taking pics of teh springs today.

-Chris

 

[Talyn]

Here are the pics of the springs that some of you wanted:

Also, here is a copy of the chart that everyone seems to use for figuring LCA and UCA length.
http://www.electronicimpulse.net/~vissagoth/jeep/misc.htm
At my heigth it appears to be no reason to mess with the UCAs. I am still tossing around the idea of JKS or RE LCAs.. and preference on which one?

-Chris

 

[RCP Phx]

Two things come to mind!
#1-it looks like you have an aftermarket steering?
#2-Your trackbar set-up may have made the angles worse!

 

[Talyn]

Two things come to mind!
#1-it looks like you have an aftermarket steering?
#2-Your trackbar set-up may have made the angles worse!

Nope, that is the factory steering. The track bar is a JKS track bar. It's frame side piviot center is about 1" lower than the stock one. However, I took an angle finder to the draglink and to the track bar (ran a piece of twine between the pivots points to get a better reading), and they were with in a degree of each other. Would that cause a wobble on a smooth surface though? I thought it would seet off a wobble over bumps only (could be part of teh problem. And since the piviot point is 1" lower than stock, wouldn't a ZJ pitman arm fix that?

-Chris

 

[climbon]

had same problem after I broke my tie rod down in Moab. I had it replaced with another cheap stock one to get home and I had a wobble at the same speeds you are talking about. Went with a complete Currie set up and the wobble is gone. I was told that cheap stock tie rods can flex causing wobble. The one I had to buy in Moab was lighter than my original stock one. I don't know maybe check your tie rod

 

[STLXJ94]

Have you thought about a bent axle shaft?

 

[Flowers]

Catching up on this thread. As I was reading through an old memory surfaced. Many, many moons ago I had a similar problem. I eventually discovered the nuts were loose on the upper end of the front shocks.

Is there any way you could swap shocks with one of the gentlemen that you swapped tires with? Could be worth your time.


Flowers

 

[Talyn]

Catching up on this thread. As I was reading through an old memory surfaced. Many, many moons ago I had a similar problem. I eventually discovered the nuts were loose on the upper end of the front shocks.

Is there any way you could swap shocks with one of the gentlemen that you swapped tires with? Could be worth your time.


Flowers

Nope, one has a 4.5" lift and the other is stock. No real good way to use either of those shocks.

-Chris

 

[Talyn]

Have you thought about a bent axle shaft?

How would I check for that?

 

[FernXJ]

I know very little about the JKS trackbar from experience. But, is it known to drop the center of the swivel(frame end) down. Have you accually measured this.
I,ve got a 00 Sport that has given me fits. Check the centering of the axle. Then from the front look at your CAs at the axle and frame(mounting points). The LCA will most likely look good. Pay close attention to the UCAs. Check to see if they may be slightly cocked to the right or the left.
Also, when I looked at my CAs after replacing with my lift I saw something bad. My right UCA was starting to wear through at the axle end. It was very, very close to tearing through!
After 2.5yrs with the lift and endless tweaking with CAs and centering with trackbar, CA sideways tilt is still not dead on.
I think that the d*** unibody is slightly not straight. You may have the troublesome type of vehicle that I've been blessed with!
Just don't get frustrated and give up. That's too easy. But, new proper length CAs and checking every mounting bolt and nut helps greatly. Bolts should be checked with not only torque but also as stated earlier(out of round)decay.
If the trackbar does drop the frame end then that also needs to be addressed. Take a tape measure and check the differences between drag. and trackbar mounting points. There is another post right now that shows their relatonship. The distance (CENTER OF THE SWIVLE POINT) at axle end of both TB and Drag should be measured from level ground. Then do the same for both at the frame end. If there is a difference between them at either frame or axle, that difference needs to be the same at frame and axle.

I know I explained this horribly, and spell like an idiot. But, somewhere in that jibberish in some tips. Wish I could show you with a pic.
Rensing

 

[Talyn]

I know very little about the JKS trackbar from experience. But, is it known to drop the center of the swivel(frame end) down. Have you accually measured this.
I,ve got a 00 Sport that has given me fits. Check the centering of the axle. Then from the front look at your CAs at the axle and frame(mounting points). The LCA will most likely look good. Pay close attention to the UCAs. Check to see if they may be slightly cocked to the right or the left.
Also, when I looked at my CAs after replacing with my lift I saw something bad. My right UCA was starting to wear through at the axle end. It was very, very close to tearing through!
After 2.5yrs with the lift and endless tweaking with CAs and centering with trackbar, CA sideways tilt is still not dead on.
I think that the d*** unibody is slightly not straight. You may have the troublesome type of vehicle that I've been blessed with!
Just don't get frustrated and give up. That's too easy. But, new proper length CAs and checking every mounting bolt and nut helps greatly. Bolts should be checked with not only torque but also as stated earlier(out of round)decay.
If the trackbar does drop the frame end then that also needs to be addressed. Take a tape measure and check the differences between drag. and trackbar mounting points. There is another post right now that shows their relatonship. The distance (CENTER OF THE SWIVLE POINT) at axle end of both TB and Drag should be measured from level ground. Then do the same for both at the frame end. If there is a difference between them at either frame or axle, that difference needs to be the same at frame and axle.

I know I explained this horribly, and spell like an idiot. But, somewhere in that jibberish in some tips. Wish I could show you with a pic.
Rensing

Al the bolts are good on the CAs.. i checked when I replaced all teh bushings but the upper axle ones (had no idea how to remove those but they stll felt good). The bushings did make a difference.. but it is still there. I will be checking the track bar and drag link relationship. I will be replacing the shocks with Bilseting or OMEs.. I have heard of a lot of problems with the DT3000s... if that doesn't work I will try a dro pitman arm (from a ZJ).. than the LCAs... I belive thats ome of the problems is coming from tht tires, but not all of it.. they are probably just making it worse. I can't afford to buy another car as I already took a bath when I got rid of the '93 ZJ (complete POS).. and I like this one too much and have too many mods in it already to get rid of it...

-Chris

 

[family XJ]

I have a wobble at those same speeds. My problem is the tires have worn a little funny. I rotate the front ones from one side to the other and sometimes it helps. I have new tires to put on tonight. Don't know if this is the answer you want or not but it's a thought. I am currently running 31 super swampers and never had this problem till they wore out. Not much help I guess but I thought I would share. Doug