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Discussion Starter #1
I've jut purchases a 2003 Rubicon that has a 3.5 lift on it and the highway steering is nothing short of frighting. No wobble or shimmy, it "darts" and is extremely sensitive to any slight input, and I guess it does what you guys call bump steer. I really wasn't interested in the lift, but the price was very good. Anyways, all the front end components are tight, aligned, and tires balanced. From what I've been reading here, I believe the previous owner did not upgrade the front end to match the lift. I'm looking for highway stability more than any other characteristic right now. There are so many things being discussed here, and I have a certain amount of confusion and need suggestions on what I should change and do to rectify this.

Thanks,

Ron T
 

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Do you know if it has a dropped pitman arm on it? If your not sure, if you can post a picture of the pitman arm we can probably tell you if it does or not. A lift that size does not require a DPA, dropped pitman arm. Any other pictures of the steering would possibly be helpful also.

My other suggestion or idea deals with the alignment. I know you said that it is in alignment, but all too often if the toe is set too far out or too far in it can create the symptoms you are experiencing.
 

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SweetPee said:
Do you know if it has a dropped pitman arm on it? If your not sure, if you can post a picture of the pitman arm we can probably tell you if it does or not. A lift that size does not require a DPA, dropped pitman arm. Any other pictures of the steering would possibly be helpful also.

My other suggestion or idea deals with the alignment. I know you said that it is in alignment, but all too often if the toe is set too far out or too far in it can create the symptoms you are experiencing.

X2 on both of the above. As Sweetpee mentioned, I'd look to alignment first. Check the toe, or have it checked. If you have a few basic hand tools, you can do this yourself at home. A very easy way is to lift the front end, pull the tires and clamp a roughly 3' long strait edge, board, piece of steel-whatever you have that is strait! to both wheel mounting surfaces. I have use a couple pieces of flatbar that is roughly 2" in width, or some 1x2 rectangle tube-whatever I have laying around. By setting that inside the lug studs, all I have to do is thread on a couple lug nuts to hold the strait edge. Works quite well. Set it with roughly half the strait edge in front and half behind the wheel mounting surface, then measure the inside (or outside) at the very front, and at the very rear of your strait edge. You want somewhere around 3/16" to 1/4" of toe in. Any more than that (or less, or toe'd out in front) and you need to make a correction. This is a very easy way to check and/or adjust at home. If you don't have any means to do this, take it to a shop ASAP to get the front checked again by a reputable shop. Do this first, post back what you find or what a shop finds, then we can all help further from there. I'm betting you're off a bit to get this type of reaction.

Also while at it, check tire pressure and balance, make sure they're all dialed in and set right. This will help many things at the same time with your ride. Not necessarily steering related, but it's good to start from a "known" good starting point or setpoint.

Best of Luck,

Mike
 

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Discussion Starter #4
Hey guys thanks a lot for the advice. Did all the mentioned advice except the alignment. I'm going to bring to a different shop for the alignment. I'll let you know what comes of it. Happy New year!

Ron T
 

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I've found that my Rubi with 33x12.5x15's are very sensitive to pressure. By experimenting I've found 28 psi to work well on road and gives a good contact pattern.
 

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By your description it sounds like a caster problem. Too much caster makes the steering feel heavy and not enough will make it very light and squirrely. Depending what the lift is and how it was installed, they may have rotated the front diff a bit and goofed up the alignment.

Jim.
 

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Jeepless in PA
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I agree with the above posts that you need to check the alignment and especially the caster angles. For a lifted rig, you are looking at 4-5degrees of caster instead of the stock 6-7degrees. The key is to remember that the driveshaft's angles always override the caster adjustment and therefore will naturally make the caster around 5. screwy how that works. :D


When I was running steel wheels, I noticed that having the circular washers that hold the rotors from the factory actually caused the jeep's alignment to be off.


edit- how to align the driveshaft. since the front shaft is a CV (constant velocity) joint, this applies.
http://www.wanderingtrail.com/Mecha...riveshaft_Alignment/Drive_Shaft_Alignment.htm

brief intro on what a Caste angle is
http://en.wikipedia.org/wiki/Caster_angle
 

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Discussion Starter #8
Just got back from getting the alignment done, and what difference! They said the toe was out significantly. I would say the overall handling improved by 60%. Thanks for all the replies.

Cheers,
RT
 

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Great-glad to hear it. Now, you mentioned it's about 60% improved-what is wrong with it now, how or what is needed to make it 100%??? In other words, what symptoms are you having now that you're not happy with?

Thanks for updating!

Best of Luck,

Mike
 

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Discussion Starter #10
It's still hard to handle, I have to really keep two hands to keep her straight. The steering is very light an sensitive. I guess I'll look into the diff angle as well. Any other suggestions? How do I check the castor?

RT
 

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Jeepless in PA
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pilotrt said:
How do I check the castor?

RT

There are two very easy methods.

1-Place a socket between an angle finder the the bottom of the front axle's C. When under the rig you will see an indentation that is about 1"x1".

2-Place a spray can on top of the upper ball joint and the angle find on top of that.
 

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Discussion Starter #12
I'll give it a go in the next couple of days and let you know. Ok, from what I've read there should be a 5-5.5 angle. Which way should that angle be?
 

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Jeepless in PA
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You want the caster to be positive. Imagine a line drawn through the front ball joints and it's intersection with a 90degree from the ground. If it is positive, your steering wheel will easily recenter verses having to put in more effort with it as negative. Imaging the steering line from the ball joints as the leading angle.

Pictures always help.


 

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Discussion Starter #14
ok, now I've got it! Thanks again! It's ice hut day tomorrow. It suppose to be -28c, -18.4F! Yikes, time for the fur lined underwear.
 

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Discussion Starter #15
I have a little more information. I have a Skyjacker 4" lift with all Jeep factory control arms. I measured the castor, and found it to be at +9 degrees. Now, do I replace just the bottom front control arms with adjustable ones or all eight?
 

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All eight is preferred but, keeping the stock lower CAs and getting adjustable uppers is better than lowers. A 4" lift with all oem CAs is perplexing to me. Others will chime in here shortly but, you are about to get deluged in differing opinions but, we're all trying to help you out.
 

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Discussion Starter #17
hey no problem.......fire away! Remember, I bought it like this, and I'm a newbie. They are definitely stock though.
 

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How deep are your pockets??? :laugh:

Four upper adjustable CAs are the least that would be needed. That gives you adjustability front and rear. If you can, go for all 8!!! The adjustable lowers are to adjust wheelbase, as you lit the jeep you loose wheelbase by a little. The uppers are for adjusting pinion angle, alignment issues, etc...

I would check out Currie's control arms or Rokmen. You cannot go wrong with either one and they will last you a life time. The Rokmen are extra stout!! But either one will be excellent!
 

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SweetPee said:
How deep are your pockets??? :laugh: ...................................
I would check out Currie's control arms or Rokmen............
Good advice, from a gentleman running RE Long CAs. He won't admit it but, the fissures are beginning to appear in his support of RE. :)
 

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f9k9 said:
SweetPee said:
How deep are your pockets??? :laugh: ...................................
I would check out Currie's control arms or Rokmen............
Good advice, from a gentleman running RE Long CAs. He won't admit it but, the fissures are beginning to appear in his support of RE. :)

I wouldn't say that. I love what I got and have no issues with it. But that system is not for everyone for sure! Are there some things I would do different, probably. But it would still be a LA setup no doubt. But far more people prefer and or want the SA versus the LA. And if it is a SA setup... I would not buy a "kit". It would be AEV springs, Rokmen CAs, Tom W. Drive shafts, JKS track bars or a cuatom TB setup with GenRight parts, a custom hiem joint steering links, and whatever belly pan I could find that tucks everything up as tight as possible and made of the thickest STEEL I could find.
 
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