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GO STEELERS !
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Discussion Starter #1
Sorry I have another thread going but wanted to post this question in Tech. I read this quote on the internet and wanted opinions on if it was true or not.

"""""Natural tendency for a Jake to pull to the right. It's caused by the unequal length front axle shafts turning at the same time, but having different torsional resistances. On FWD cars this was solved decades ago by using shafts with the same torsional resistance, but that's hard or impossible to do inside a solid axle housing. So, Jeep staggers the caster on the JK slightly, about .2 degrees more on the right side. Teraflex and a couple other lift kit mfrs suggest a slightly longer lower right control arm setting to correct this, about 1/8 to 1/4" ought to do it. Bear in mind all this assumes everything else is set up right. Get it on an alignment rack, get the readings and compare them to the factory specs."""

If it is I may advice my alignment shop so they can adjust and hopefully solve my pulling issue.
 

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Yep that's the way I've got mine setup, but then again it never pulled or wondered with stock
CA's and castor at 3.3* so IDK.......
 

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I've never heard that... I find it difficult to apply the small amount of rotational mass difference as a cause for pull.

This is the common theory:

CASTER: Caster is the position of the steering axis from true vertical when viewed from the side. The caster angle is formed by the steering axis and a true vertical line passing through the spindle. The purpose of caster angle is to provide directional control stability for the front wheels to travel a straight course with minimal effort. Proper caster angle also helps to return the front wheels to a straight ahead position after a turn. Caster is adjustable on most short/long arm suspensions on passenger cars and light duty trucks to compensate for normal wear in suspension and steering. Positive Caster is the backward tilt of the steering knuckle at the top. This places the vehicle point of load ahead of the point of contact at the road surface, which provides good directional control. Negative Caster is the forward tilt of the steering knuckle at the top. This places the point of contact ahead of the point of load, which provides easier steering at slower speeds. Negative caster does not provide good directional control stability. The vehicle must instead rely on its SAI angle and wide tires for directional control. Caster is a directional control angle and can be used offset road crown on most short/long arm suspensions. Unequal caster causes the vehicle to pull to the side with the least positive caster. Unequal Caster Effect – to offset road crown, the top left steering knuckle is always leading the right; the right side has more positive caster. Too much positive caster out of factory specs causes hard steering and excessive road shock and shimmy. Too much negative caster causes instability at high speeds. When caster is out of factory specs, the vehicle should be checked for loose, worn or damaged suspension and steering parts before alignment.
 

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I've heard it both ways. By running longer arms on one side, you're putting the axle in a bind. Not good for bushing and mount Life.

Do you have 8 arms ? Its possible the factory mounts are slightly off. Even length arms are what's causing the pull. Set up each arm so there's 0 bind and see what happens. Does this makes sense ?
 

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Op... on FWD cars, unequal half shafts creates torque steer and the pull mostly occurs when you nail it from a standing start. I've heard of guys adjusting arms to square the chassis.. but not for compensating for unequal front axle length. I'm not sure that would make as much difference let's say for example as two different diameter tires on the front... or pitch of the road for runoff. But I know what you're saying - most often, there appears to be a slight wander to the right when you have a live axle in the front.

My XJ had it periodically.. it got more pronounced the more I lifted using short arms. But I think that's due to uneven tire wear and effect from the pitch in the road.

To me - there's a difference between wander and pull. Pull you feel in the steering as you drive and constantly need to correct and typically is alignment related. Wander is felt more by the effect from live axle movement, which slightly impacts camber angle, uneven tires and pitch in the road.

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GO STEELERS !
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Discussion Starter #9
What are your caster numbers ? Low the jeep will tend to follow road imperfections and the crown. Does it happen on the highway or just around town ?
Getting my print out in an hour. Slow speeds unnoticeable. Over 40 you real start felling it. Highway roads. Flat or crowned it pulls.
 

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GO STEELERS !
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Discussion Starter #11
I've heard it both ways. By running longer arms on one side, you're putting the axle in a bind. Not good for bushing and mount Life. Do you have 8 arms ? Its possible the factory mounts are slightly off. Even length arms are what's causing the pull. Set up each arm so there's 0 bind and see what happens. Does this makes sense ?
Yea all 8 arms
 

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GO STEELERS !
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Discussion Starter #12
Hey look I'm a poet rofl Btw .. Improper toe will also cause steering issues.
It's funny you bring up toe. The front right looks visible off. Standing dead front of it the right front looks slightly angles out. Dealer looked at it but of course wouldn't say yes or no so back on the rack in an hour or so with a print out of numbers. Lol maybe I am going nuts and just want it to be toed out but that's what it looks like to me. I tried to take a pic but the iPhone quality is t good enough.
 

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It's funny you bring up toe. The front right looks visible off. Standing dead front of it the right front looks slightly angles out. Dealer looked at it but of course wouldn't say yes or no so back on the rack in an hour or so with a print out of numbers. Lol maybe I am going nuts and just want it to be toed out but that's what it looks like to me. I tried to take a pic but the iPhone quality is t good enough.
The Flares angle in which gives the appearance of toe out. It's probably just a illusion.
 

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your after numbers look good maybe you have a bad tire.
 

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GO STEELERS !
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Discussion Starter #19
Steering was off center beforehand. A bit too much toe as well.
How is it now ? Caster looks great.
Well that rules out alignment I guess. It still pulls and is most noticeable above 40 MPH. I am going to start taking one tire off and a time and replacing it with my spare to see if I can determine which tire it is.
 
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