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Sinton
January 1st, 2010, 19:54
Is there a difference between a Death Wobble and wandering around the traffic lane? (wandering being like not having good steering control, as if blown by the wind)

I've posted some stuff before about this issue, but I'm confused about what, if any, differences there are.

On a side note, should ball joints be replaced on both sides if you are replacing them?

I have an RE 4.5" super-flex kit, installed a Currie tie-rod and drag bace, replaced the right front hub assembly, right upper/lower ball joints, right axle u-joint, right caliper, and even the sway bar brushings. Tires rotated and allignment has been completed. Steering is horrible at all speeds.

Had a mechanic check out the ball joints I installed. He said I did not get them seated fully, he seated them. Steering was good for a bit, now it is back to bad. No unusual noises from drivetrain or axles. I'm going on two months trouble shooting this and now my wife won't ride with me.

Guidance would be appreciated. And if anyone knows any good shops in the DC/Northern Virginia/Maryland area that specialize in our modified jeeps? Seems like normal mechanics are lost on these.

Tim_MN
January 1st, 2010, 21:41
What did you do about the Track Bar when you lifted the Jeep?

Death Wobble is pee your pants scary. The whole front of the Jeep shakes uncontrollably until you get stopped.

Make sure you get an alignment from a shop that understands lifted vehicles. If you got an alignment from a chain store that sell tires and performs alignments, your alignment is probably to stock specs and you will experience extreme tire wear and odd handling.

MoFo
January 2nd, 2010, 05:44
To troubleshoot DW and loose steering, the first thing you need to do is lay under the vehicle and watch the steering while you have a helper move the steering side to side at your command. Look for play in the TREs and both ends of the track bar. There should be zero play at all these points. What track bar do you have installed? Make sure there is no play where the upper (drivers side) mounting bracket bolts to the frame rail.

bdiamond
January 2nd, 2010, 06:05
There is a youtube video of Deathwobble. You'll know it if you have it. Its really pretty unmistakable once you experience it. I thought it was a pretty exagerated term until my Jeep got deathwobble. Mine was a bad control arm bushing and trac bar bushing.


Edit: Here it is...http://www.youtube.com/watch?v=wj9PNNChVm4

winterbeater
January 2nd, 2010, 07:08
First of all, climb underneath and have your wife turn the steering wheel back and forth about 1/2 turn. Look for free play anywhere from the tie rod ends to the steering box and track bar ends.

Once it is all tight (no play) set up your alignment like this: shttp://www.go.jeep-xj.info/HowtoAlignment.htm

DeftwillP
January 2nd, 2010, 07:44
If you're having wondering at all speeds, it's your caster. What lengths do you have your arms set to?

Sinton
January 2nd, 2010, 09:38
Im heading away for a few weeks, till then the Jeep will sit. So it's not a deathwobble that I have. Thank you all for clearing that up. It's a wandering issue.
Im using an RE trackbar.
As for caster, I'll have to measure when I return. How do you know what length to set?

xcm
January 2nd, 2010, 12:49
sounds like you have bumpsteer (1 tire hits a bump, or dip, and it pulls the entire front end in that direction)
with a touch of death wobble.

bumpsteer comes from mixmatched draglink/trackbar angles. death wobble comes from worn or out of alignment/balance parts.
what kind of steering do you run?

JRW7072009
January 2nd, 2010, 16:25
We call it chasing the grooves in the street, it is normally caused by large tires and low caster. Your steering can also have a factor in it. Is it normally near the intersections? This is where it normally does it the most, at least from my experience with it.

Low caster angle can cause bumpsteer and cause it to wonder with the grooves in the road. Its very common with lifted vehicles

Sinton
January 2nd, 2010, 21:16
What is the difference between high and low caster angle? I did look up caster to find out what that is. Caster is affected by the control arms Im assuming.

How do you know what the correct draglink/trackbar angles are?

I am running a Currie Enterprise CE-9701 tie-rod draglink and the RE trackbar that came with the kit.

Since this is common with lifted vehicles, is there a way to minimize the "chasing?"

I'm gonna be out of touch for a few weeks, so I'll use the insights to take a fresh look at her when I return. Thanks for the input.

winterbeater
January 3rd, 2010, 08:53
Caster is easier to understand in a motorcycle. Like a chopper with an extended front end has HIGH caster angle. They go straight ahead good and are hard to turn. If you have ever ridden a minibike, you know what LOW caster angle is. The steering is almost straight up and down and has NO stability. On your XJ, it is the angle as determined by a line through the ball joint pivot points. You pretty much need a wheel alignment machine to measure this, but the link I posted earlier shows a way to check and correct this using simpler and "quick and dirty" methods which work.

JRW7072009
January 3rd, 2010, 10:33
Caster is easier to understand in a motorcycle. Like a chopper with an extended front end has HIGH caster angle. They go straight ahead good and are hard to turn. If you have ever ridden a minibike, you know what LOW caster angle is. The steering is almost straight up and down and has NO stability. On your XJ, it is the angle as determined by a line through the ball joint pivot points. You pretty much need a wheel alignment machine to measure this, but the link I posted earlier shows a way to check and correct this using simpler and "quick and dirty" methods which work.

X2
Adjustable CAs is the best way to correct your caster angle. Either uppers, lowers or both. To gain caster you need to push the LCAs out, or shorten the uppers. IMO it best to push, or lengthen the lowers out. You may be able to gain some more caster angle with shimming your LCA mount.

joe_peters
January 12th, 2010, 19:02
X2
Adjustable CAs is the best way to correct your caster angle. Either uppers, lowers or both. To gain caster you need to push the LCAs out, or shorten the uppers. IMO it best to push, or lengthen the lowers out. You may be able to gain some more caster angle with shimming your LCA mount.

Shimming the LCA mounts at the unibody is the cheapest way, if your caster is not too far out. I run mine at 7 degrees positive, the FSM 90 says 5~9 degrees Ok, set to 6 degrees.

Doctor94R
January 12th, 2010, 22:48
Where do you guys take your caster angle readings from? When I set up my long arms on my HP30 I took the reading from the bottom of the inner C. Set them to about 5 degrees, but I have horrible wander sometimes when hitting patched ruts or following the tracks in the road. (I do contribute some of my wondering to the clunking track bar that is getting replaced this weekend though!!)

Anyhow, I followed this site (http://www.go.jeep-xj.info/HowtoAlignment.htm) for caster angles. One thing I don't understand however, is how the low pinions run higher caster angles (as in the axle is rotated back) than high pinion axles? Wouldn't the low pinions have to point the ujoints up towards the TC more? Which would cause lower caster angles?

RCP Phx
January 13th, 2010, 04:38
Anyhow, I followed this site (http://www.go.jeep-xj.info/HowtoAlignment.htm) for caster angles. One thing I don't understand however, is how the low pinions run higher caster angles (as in the axle is rotated back) than high pinion axles? Wouldn't the low pinions have to point the ujoints up towards the TC more? Which would cause lower caster angles?

They dont typically!