Cross Caster issue - any solutions?

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Mar 20, 2007
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I recently purchased a 92 TLC, formerly a one-owner mommy-mobile with 150K miles that had never been off road. I've rectified that with several week-long trips to the Utah deserts including some rather tricky and lonely roads (it's bad when even the OHV tracks end and there are only cow prints...)

In any case, here's my problem. The truck pulls annoyingly to the right--mostly a problem on the highway. Alignment numbers that came with the truck:

Left
camber: .2
caster: 2.7
toe: -.01

Right
camber: .3
caster: 2.0
toe: .04

cross camber: -.2
cross caster: .7
total toe: .03

Tires have been rotated with no change. I suspect the cross-caster is the culprit, but haven't figured out if there is a way to fix it short of getting a new front axle.

I am likely to go with an OME 2.5" lift & 33" tires soon, and wonder if tricks could be played with the OME caster correction bushings, but it seems that this would just average out the correction and do nothing for cross-caster problems.

Has anyone had cross caster problems and figured out how to correct them (or at least get rid of the pull to the right)?
jan07 101sm.jpg
 

landtank

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I fixed a fellow mudders truck with a bad pull to the right by replacing the tie rod and both ends. There is a thread by me that describes how to evaluate a front end. Following that procedure should reveal the problem.
 
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Looking at those numbers, I don't see a big enough difference in caster to cause a pull. How bad is the pull? Does it correct itself when the brakes are applied? How many miles since last alignment? If those numbers are still good, I would look into a drag issue on one side. ie: caliper, stuck pad, wheel bearing, ect.
 
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more info...

Thanks for the quick reply. I found the front end faq and will go through it again, though I checked for play in all those tests except the trunion bearing test when I bought the vehicle. There is no slop in the steering, btw (less than 1" freeplay in the wheel).

However, when offroad and under high articulation I periodically get a pretty solid "thunk" from something shifting around--probably on the front right axle somewhere. My guess is maybe a trunion or wheel bearing shifting, but maybe something else?

BTW, the pull is pretty dang annoying on the freeway--have to hold on at all times or end up in the next lane/off the road. It isn't really all that noticable off road or in town (but still present). The alignment numbers aren't too current (2000), but came with the note from the tech "There is no caster adjustment on this vehicle so we can not compensate for the slight drift to the right". Thus I know the problem has been there for a while.

It isn't a stuck caliper, btw... Brakes are good.

If I can fit 33" x 10.5" with the stock suspension (folks on this forum say it works), then I can go get new tires and a new alignment check before doing the lift.

But the question remains: is there any way to fix cross-camber issues if they exist?
 
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You can fit 33x12.50s on stock suspension, and stock wheels. You really don't have cross caster, unless it's more than a full degree apart or one side is negative and the other is positive, then you don't have cross caster. Your toe on the other hand is off, and is the reason for you pull.

Right side is pointed .1* out, left side pointed .4* in. Get the alignment shop to adjust your toe to about .2* in on both sides.

The clunk is probably your tie-rod ends, fresh ones from CruiserDan or Slee Off-Road would help.
 

Waggoner5

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Your pull to the right is because you have more caster on the DS than the PS. You should have 3/8-1/2 degree lead or more caster on the PS. Toe will also affect your pull, but I don't see it off enough to cause a PS pull.
 
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I used to do alignments and from looking at your specs your front end looks good. What is your thrust angle?? Should be on your printout. Meaning your rear diff could be pointed in the wrong direction.
 
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thrust angle?

Thanks to everyone for the quick replies.

The alignment numbers I have are for the front only. If the back end could be causing a pull to the right, then I need to get it down and have the back end measured as well. I suppose that begs the question of what is adjustable in the back end...

I'll just assume since nobody has any ideas to the contrary, cross caster isn't adjustable without finding a new front axle (I can't see how it would be). Toe is slightly off but within specs. If I understand correctly, if both wheels toe to the same side, that just results in the steering wheel not being centered, and total toe is the more interesting measurement anyway (correct me if I'm wrong here).

btw, I just jacked and found that the DS front wheel bearing is loose--which would explain my off-road clunking during articulation. It's definitely time for a wheel bearing & birfield rebuild, but hopefully I can tighten it and make it another 1000 miles to get back to my well-stocked garage. No unpleasant wheel bearing noises yet, at least.

I'm real curious about how the back end could lead to a pull, since everything seems pretty good about the steering setup and it feels quite good other than the pull to the right (no wobbles, steering is tight, handles well, etc).
 
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update

I measured the wheelbase left and right, and got about a 1" discrepancy (this wasn't super accurate, but I did it twice). The wheelbase on the right (PS) was about 1" longer than on the left.

Any suggestions on how it might have got this way and what to do about it? Again, I'm almost certain the vehicle has never been wrecked, and I didn't see anything obviously amiss (like missing bushings or anything). Does this sound like a cause for a pull to the right?
 
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7yrs is a long time, take it in for an alignment. Caster may cause a "drift" in one dirrection or another, but rarely a pull. Get some fresh numbers and see what comes up. Anything less than a degree difference in caster side to side is fine.
 

landtank

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get the wheel bearing fixed and see what happens.

I'm assuming you are measuring hub center to hub center for the wheel base. That measurement will differ largely based on where the front wheel are pointing. I don't think what you are seeing is anything to worry about at this point.
 

Waggoner5

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But gary, are his tires not both pointed PS?

Yes ,but normally this would just cause you to correct for steeering wheel angle and would not necessarily cause a pull.

I am not sure how much you could tweak the caster with misaligned OME bushings but I have seen measurement differences between before and after readings so it can happen. You are looking for 1 full degree on PS to get it close and I am not sure you can get that.

The wheel bearing should help camber readiings, but you are not off by much in that area.
 

landtank

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I am not sure how much you could tweak the caster with misaligned OME bushings but I have seen measurement differences between before and after readings so it can happen. You are looking for 1 full degree on PS to get it close and I am not sure you can get that.


The one thing the bushings can do if they are not installed identically on both arms is to cause the axle not to be positioned straight on the truck.

So it can sit further forward on one arm than the other. I'm not sure if this will cause a pull or how it would interfere with the caster reading.
 
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Pull to the right solved...

OK, the pull is mostly solved. Both front wheel bearings were loose. Had to do the quick & dirty for now (tightened both with the 10lbs/47lb trick) until I get back to my garage in CA when I'll do a full birf & wheel bearing rebuild.

Put on 33 x 10.50 x 15 tires to replace the 31s. Tire shop thought the spare didn't fit, but it fit with plenty of room.

Had the alignment checked:

Before - Front:
Camber: Left: .1 Right .3
Caster: Left: 2.7 Right: 2.1
Toe: Left: -.13 Right: .21
Total Toe: .08
Steer Ahead: -.17

Rear:
Toe: Left .29, Right -.27 (total: .03)
Thrust Angle: .28

After:
Camber & Caster the same (non-adjustable)
Toe: Left .06, Right .04
Total: .09
Steer Ahead: .01

Only the very slightest pull to the right now, but perhaps just road crown...

Thanks for everyone's input.
--brendan
 

landtank

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Give it some time for the tires to wear a little to there new spot. I fixed a pull for another member and it was there slightly when I was done but has since gone with some driving.

The "quick and dirty" is the only way I roll!
 
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"Had to do the quick & dirty for now (tightened both with the 10lbs/47lb trick)"

Newb question: What exactly are you tightening.
 
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Is there a thread detailing how this is done?

My front tires are rapidly burning tread on the outsides. Can this method help correct it?
 

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