LJ with 3 1/2" lift + factory control arms = wobble at 40mph

[Jason7140]

This is the case and was wondering if anyone knew for sure if longer aftermarket control arms would stop the problem. It is not the track bar. Had a Fulltraction adjustable with the tie rod like end, but switched to a Rubicon Express adjustable. No movement there and everything is centered. Alignment has been done 3 times and is good. 33" BFG's are properly inflated and balanced.

Tell me the control arms are too short and it is pointing the front axle slightly down which is the root of the problem.

 

[jps4jeep]

yes and the factory bushings are also probably junk from driving like that which is also a contributing factor.

 

[Utah_jeepster]

Did you put a new drop pit man arm on the idler arm/steering box when you put in the 3.5 lift? You are also right at the point where the rear drive line angle could be giving you some vibration as well.
If its steering a new drop pitman arm will drop the front idler arm down enough to bring it back closer to being parallel.
If its not a steering issue then adjustable lower control arms will bring your caster back into line.

 

[jps4jeep]

Drop pitman arm will do little to cure a wobble if that is indeed the issue, generally a drop pitman arm will solve bump steer.

His caster being close to zero is more than likely the problem.

 

[Jason7140]

I have a dropped pitman arm, but haven't yet installed it. I haven't had any bump stear issues yet. I have installed a heavy steering stabilizer, and it helped a little, but the factoty steering stabilizer wasn't the root of the problem either.

The jeep has a 3/4" spacer in the front, but not the rear, so really it sits on 3 3/4" suspension lift front, and 3" lift in the rear. I mention this because even with out the 1" motor mount lift which I have done, the rear drive line angle on the LJ was still adaquate.

Heart and soul I knew the answer was control arms. I just needed someone else to access the situiation. Thanks for the input guys.

 

[jps4jeep]

stabilizer won't do poop for bump steer. because the drag link and trac bar are not parallel, when the suspension compresses, cycles or just about any type of movement, it will cause you tires to turn slightly even though you did not actually turn the steering wheel.

 

[jps4jeep]

if your fab-crafty, you can lengthen and make your own control arms from your old ones. doesn't take much. I saw a thread on it on another board, let me search.