So long story short, i get a 08 JKU with a 3.5 to 4 inch Treaflex lift about 16 months ago and i"m sure it was totally hammered every day in Moab by its previous retired owner. Oh its got stock rubicon tires and wheels buy the way.

That said at speed 60-70-60 MPH its started to get really light on the steering and starts to wander. in the last 2 weeks I have put the Currie heavy duty steering on drag link and tie rod with all new ends, replaces all the ball joints, upper and lower, new power steering pump, new power steering box and had it aligned. its better than it was but again now at 70 its drifts around on the freeway if your not watching it.

Yesterday my wife and i went out in and she commented that it really rolls around when being driven and round corners she surprised i have not lifted a wheel and i guess thats when i stated to really notice it too. I checked and checked again all the suspention and sway bars are tight and the bushing are all good sooooooo...........

is it possible that very soft springs rates from years of use/abuse and/or worn shocks could cause this? the more i think about it this morning makes me think so but i'm always looking for a second opinion. replace the shocks next perhaps?

just to add one more thing on a straight run on the freeway at 80 it handels fine, its when its windy or the road curves that it seems to want to be off in the weeds.. thughts?

Thanks
Dave

 

Not sure this is relevant.. but here goes.. We've had our new shocks on since Aug.. in the beginning things appeared to be fine.. the jeep handled all the bumps but was a tad bumpy. I've been reading that many jeepers are removing the 14mm bolts and replacing them with 9/16 bolts.. as a mean to reinforced the jeep stability. $40 buck worth of work and the new bolts are in.. we're still suffering the stiffness issue with the shocks but the turning radius and pure handling of the jeep have increased because of the bolt upgrade. Is it possible that your shocks have surpassed their life expectancy?. and would the bolt upgrade off any more or less based on what your feeling upon driving the jeep. Perhaps the steering stabilizer isn't the correct one or even mounted in the correct location.

 

With that much lift, do you have adjustable front control arms?

 

Thanks for the thoughts, it may be the shocks are just totally beat and the the bolt holes could have enlarged over time. the bolt swap is easy so i'll do that when i do the shocks.

To answer your Jeepstin12 yes the lift kit has aftermarket teraflex aftermarket lower that are adjustable. do you think i dont have enough caster on the front and is there any way to measure that without an alignment rack? What would be the ideal measurement for 3.5 to 4 inches of lift?


thanks
Dave

 

Seems like you covered everything front end related... By chance do you have alignment specs after the work done... On a side note after I did the ball joints and drag link on mine I experienced similar symptoms because I wasn't used to the quick response from fresh components...

 

When I did my lift I set the caster with a simple angle finder from home depot. You can use the flat spot on the axle C to check the angle. It should be close to 4 degrees.

 

Stock caster is around 4 degrees. After a 3-4" lift, it may be down toward the low 3 degree range, which could be the cause of the steering feel. Many people will put the caster up around 5 degrees with that height lift. But if I read your post right, the wandering just started, with no other changes? And you have adj front control arms? That seems more likely to be worn/loose components, or maybe you were offroad and bent something?

Some alignment shops will throw it on the rack and print out the 'before' specs for free. You might see if you can find one. If so, post both the caster and toe specs. If not, go up to the Writeups area. Stuck to the top is an index. Scroll down to the troubleshooting or steering sections and find the DIY alignment writeup. (the links were still broke the last I checked, just scroll down). That will show a way to check using a cheap angle finder. It is not as accurate as a shop, but will get you in the ballpark of what the caster is set to. It will also show how to check the Toe.

Do you have a rear trackbar relocation bracket? (might be dropping from the frame, or raised from the axle.) Is there any steering correction? (might be a drop pitman + trackbar drop bracket, or a drag link flip + trackbar raise bracket)

New tires? Which brand, size, and psi?

 

Sorry I was not clear when I started the thread. It's always been like this from the day I got it so my plan as been to do upgrades as needed to try and pin point it. There are no drop brackets for the track bars front or back but I plan to add some and flip the draglink when I get some new wheels with smaller back spacing.
Thanks
Dave

 

That seems kinda backward. Pinpoint the problem so you aren't throwing money at components you don't need.

Check the caster. If it has always been low (flighty steering), and you have adj arms, that's a super easy fix to the situation. A rear raised trackbar bracket will help with the roll center, which changed with the lift height. A flip, you may or not notice a difference in the before/after handling, but at least it will raise the front trackbar. Just be sure to bumpstop properly to keep it off the frame.

 

If none of that list of things has changed how the jeep drives then one of the few things left would be to check the caster as others have stated. Light caster will definitely cause flighty steering/ wandering on the highway. Caster should be 4.2-4.5 degrees but you can air on the heavier side and upwards of 5 degrees.

RK