Project X= Alignment questions???

[Albino 94LTD]

My last alignment had caster angles of 6.2*, yours are even more positive. I think being that positive accentuates the effect of cross camber.

Here is an excerpt from 'wheel alignment, a short course'

When you turn the steering wheel, the front wheels respond by turning on a pivot attached to the suspension system. Caster is the angle of this steering pivot, measured in degrees, when viewed from the side of the vehicle. If the top of the pivot is leaning toward the rear of the car, then the caster is positive, if it is leaning toward the front, it is negative. If the caster is out of adjustment, it can cause problems in straight line tracking. If the caster is different from side to side, the vehicle will pull to the side with the less positive caster. If the caster is equal but too negative, the steering will be light and the vehicle will wander and be difficult to keep in a straight line. If the caster is equal but too positive, the steering will be heavy and the steering wheel may kick when you hit a bump. Caster has little affect on tire wear.

The best way to visualize caster is to picture a shopping cart caster. The pivot of this type of caster, while not at an angle, intersects the ground ahead of the wheel contact patch. When the wheel is behind the pivot at the point where it contacts the ground, it is in positive caster. Picture yourself trying to push the cart and keep the wheel ahead of the pivot. The wheel will continually try to turn from straight ahead. That is what happens when a car has the caster set too far negative. Like camber, on many front-wheel-drive vehicles, caster is not adjustable. If the caster is out on these cars, it indicates that something is worn or bent, possibly from an accident, and must be repaired or replaced.

 

[Tbars4]

..do'h, i should have posted this earlier...:confused

left front __specified range_______ right front
0.32 ____ -0.25-0.75______camber____0.37
6.59 ____ 2.00-7.00 _____ caster ____6.54
-0.01_____ -0.10-0.16______toe______-0.02

Front____________________specified range
cross camber = -0.05_______-0.50/ 0.50
cross caster = (0.05)______-1.25/-0.25..(=not good)
total toe____= -0.02_______-0.19/0.31

...after reading that and this report, having the steering wheel slightly left and the truck pulling slightly right, to me, it feels like a toe issue...
...what i can't figure out from all this is what a bigger bushing could do with the above specs...if what i read in your post is true, a little positive caster would not be to bad if it helps correct what i think is the toe...:scratch:

 

[4x4junkie]

If all your frontend bushings are good, I wouldn't really worry about the numbers themselves much. The fact is it's pulling right, which normally would mean you need to add a bit more caster angle on that side (or take away a bit on the left side).


I'd get the brakes squared away first though before you do anything further with the alignment.

 

[Tbars4]

...would adding the caster angle on the right side bring the steering wheel back to center???...:scratch:

...as for the brakes pulling, the guys left greasy hand prints on the left rotor...

 

[4x4junkie]

That certainly could do it (your brake pads are probably contaminated with grease now)

Centering the steering wheel is done on the tierods. You'll need to turn one side a certain amount, then compensate by turning the other side the same amount so the toe doesn't change.

 

[Tbars4]

...thats what i normally do when i stringline it myself...the reason i asked is this is the first alignment i've had that they weren't concerned that the steering wheel was off...

...but, from what yourself and albino posted if the guy puts a bigger bushing in and the caster on that side goes positive, it will not hurt tread life, but i might get some bump steer...:scratch:

 

[Anime]

Going just by the numbers, and assuming the "specified range" works as well for the lift and larger tires, it's obvious theres positive camber, the caster is at the upper limit, toe-in is off, and so the cross/total measurements are off.

Have you already inspected everything throughly? Brackets, bushings, etc? Alignment won't solve a larger hardware issue, though you can sure spend a lot of time and money at the shop trying. Once everythings good, it's not usually too hard to check the toe and camber, and if the camber is ok, just adjust the toe-in as needed with the steering. If the camber is still positive (assuming you'd want just a bit of negative camber), then shims come into play so you can get it.

Yeah, alignment shops don't tend to worry about the steering wheel being straight, and they tend to skip out on other details, like having the driver IN the vehicle during the alignment since, you know, you want the thing to be aligned for when you're driving, not when the car is parked.

I wouldn't agree to adjusting anything just for caster, usually getting the right camber and the right toe results in the right caster. Adjusting for caster is usually backwards, since it's likely to change the other alignment settings and you'll have a nice caster readout on paper, but a bad alignment.

 

[Tbars4]

...by the numbers, only the cross caster is out...but the pulling to the right bugs me...everything was checked by me before i even thought about getting an alignment and they checked the usual, uppers and lowers and the steering rack...

...the only thing i haven't checked is to see if the spindle on the right side is bent itself...thats out of the blue but that is the side i had to replace the rotor on that i kept having spindle nut looseness before...

...let's just say i've got one more chance for them to fix the steering wheel alignment and the pull to the right...

 

[91exploreron37]

Hmmm sounds like you may have two problems then, The alignment is causing it to pull to the right and it pulls to the left because the brakes are grabbing from the grease contamination. I'd take it back and have them replace the pads since they left grease on it.