Steering Wheel Wont Centre After Wheel Alignment

[87manche]

because it's an inverted y the draglink goes directly to the passenger knuckle.
http://www.rockcrawler.com/techreports/currie_steering/large_pics/pic08_stock.jpg

you need to straighten the passenger side wheel.
Adjust the tie rod so the toe is correct on the drivers side wheel
Then use the collar at the top of the draglink to adjust the steering wheel position.
The collar at the top of the draglink will not affect the toe adjustment drastically. It should be a simple re adjustment on the tie rod to correct it.

 

[mattyj]

Awesome... thankyou for the expaination.
.
Now i need to go and re-adjust my steering!

 

[Ray H]

because it's an inverted y the draglink goes directly to the passenger knuckle.
http://www.rockcrawler.com/techreports/currie_steering/large_pics/pic08_stock.jpg

you need to straighten the passenger side wheel.
Adjust the tie rod so the toe is correct on the drivers side wheel
Then use the collar at the top of the draglink to adjust the steering wheel position.
The collar at the top of the draglink will not affect the toe adjustment drastically. It should be a simple re adjustment on the tie rod to correct it.

Draw yourself an inverted Y setup and lengthen just the drag link, you will see that the angle of the "y" decreases and does effect the tow. Its not much if any on a stock Jeep but it does change things more on a lifted Jeep.

 

[Johnny O.]

you need to straighten the passenger side wheel.
Adjust the tie rod so the toe is correct on the drivers side wheel
Then use the collar at the top of the draglink to adjust the steering wheel position.
The collar at the top of the draglink will not affect the toe adjustment.

This is the way I did mine. 87manche first step was to straighten the passenger wheel. I did this with the steering wheel and verified it was straight with a string from the front wheel to the rear. Once I got that one straight I moved on in the same order as manche. I found some specs for a 1989 model online (I have a 91) and it said that the tow should be set at 0 for models with the auto tranny and 1/8” tow in for the 5 speed. I left mine at 0 even though I have the 5 speed and have no problems but could someone tell me why their would be a difference in the two?

 

[Ray H]

you need to straighten the passenger side wheel.
Adjust the tie rod so the toe is correct on the drivers side wheel
Then use the collar at the top of the draglink to adjust the steering wheel position.
The collar at the top of the draglink will not affect the toe adjustment.

This is the way I did mine. 87manche first step was to straighten the passenger wheel. I did this with the steering wheel and verified it was straight with a string from the front wheel to the rear. Once I got that one straight I moved on in the same order as manche. I found some specs for a 1989 model online (I have a 91) and it said that the tow should be set at 0 for models with the auto tranny and 1/8” tow in for the 5 speed. I left mine at 0 even though I have the 5 speed and have no problems but could someone tell me why their would be a difference in the two?

I dont know why the difference. Ive read there is also a difference if you have a 242 or 231 t-case. For a 242 the tow should be 0 but for a 231 it should be -1/8".

 

[Rick Anderson]

If you raise the vehicle, you have to adjust Toe, don't you. Because it changes the angle on the drag link and correspondingly the Tie-Rod. Remember your High School Geometry, if you change the angle while one side stays the same length, then the length of the other sides of a triangle have to change. The other side of the triangle is the toe adjustment.

Now, adjusting just the drag link. Your changing the length of the drag link, that is going to change the angle of the drag link, which correspondingly changes the angle of the tie rod. Tie-Rod angle changes, toe changes.

BUT, most drag link adjustments are going to be what +/- 2% of its overall length, and the corresponding angle change and corresponding toe change, is going to be, I don't know 0.25%? Basically a small drag link adjustment will result in such a tiny toe change it should still be in spec and NOT cause any problem.

If your going to make an enormous Drag Link Adjustment, like spin the steering wheel one full turn, the change may be big enough to change toe enough that it goes from being negligible and within spec to significant and out of spec.

 

[Ray H]

If you raise the vehicle, you have to adjust Toe, don't you. Because it changes the angle on the drag link and correspondingly the Tie-Rod. Remember your High School Geometry, if you change the angle while one side stays the same length, then the length of the other sides of a triangle have to change. The other side of the triangle is the toe adjustment.

Now, adjusting just the drag link. Your changing the length of the drag link, that is going to change the angle of the drag link, which correspondingly changes the angle of the tie rod. Tie-Rod angle changes, toe changes.

BUT, most drag link adjustments are going to be what +/- 2% of its overall length, and the corresponding angle change and corresponding toe change, is going to be, I don't know 0.25%? Basically a small drag link adjustment will result in such a tiny toe change it should still be in spec and NOT cause any problem.

If your going to make an enormous Drag Link Adjustment, like spin the steering wheel one full turn, the change may be big enough to change toe enough that it goes from being negligible and within spec to significant and out of spec.

I agree 100%.
On a stock truck, not a big deal, but if you lift it high, then it could be an issue and then in this case (spinning the steering wheel completely around) it is definately an issue.

 

[87manche]

Draw yourself an inverted Y setup and lengthen just the drag link, you will see that the angle of the "y" decreases and does effect the tow. Its not much if any on a stock Jeep but it does change things more on a lifted Jeep.

true, but if you adjust the toe, and then do the steering wheel you'll be in the ballpark.
Rather than guessing at where the wheel will be straight.
So, I do toe first, then the steering wheel.
Then I readjust the toe. It's usually very insignificant, and I didn't even see much of a difference on the tape measure and I'm at 4" up front.

 

[87manche]

I dont know why the difference. Ive read there is also a difference if you have a 242 or 231 t-case. For a 242 the tow should be 0 but for a 231 it should be -1/8".

that's because the 242 case can be used on dry pavement, and as such whatever wheel is getting power through the open diff will want to steer the truck.

231 cases are not to be used on dry pavement, so the toe is set 1/8 in to provide better straight line tracking.

 

[Ray H]

true, but if you adjust the toe, and then do the steering wheel you'll be in the ballpark.
Rather than guessing at where the wheel will be straight.
So, I do toe first, then the steering wheel.
Then I readjust the toe. It's usually very insignificant, and I didn't even see much of a difference on the tape measure and I'm at 4" up front.

Im agreeing with everyone, drag link adjustment doesnt make MUCH difference in tow, but the question was asked "why does adjusting the drag link effect tow" so I answered the question. It does effect it, probably not significantly though. Although in a situation like the OP has, it would significantly effect it and if you were going straight from stock to 6" of lift, it may be significant, thats all Im saying.

 

[Ray H]

that's because the 242 case can be used on dry pavement, and as such whatever wheel is getting power through the open diff will want to steer the truck.

231 cases are not to be used on dry pavement, so the toe is set 1/8 in to provide better straight line tracking.

That makes sense. Im not clear on the fundamentals on why tow in is better for straight line tracking though. Im not saying I dont believe you, Im saying I dont know the science behind it.

 

[87manche]

it's like a dynamic tension in the front end. WHen you're driving forward the tires actually move a bit.

This explains it much better than I can

The toe setting is illustrated with these two diagrams. Illustration A shows toe-in where the leading edges of the tires are closer together than the rear of the tires. Toe-out is the opposite. For proper steering, straight-line tracking, and tire wear, the steering should be set up with a slight amount of toe-in because the truck's forward motion actually pushes the wheels to a zero toe attitude.

from here:
http://www.off-roadweb.com/tech/0212or_steering_information/

 

[Ray H]

Ok, I got it.

 

[Johnny O.]

it's like a dynamic tension in the front end. WHen you're driving forward the tires actually move a bit.

This explains it much better than I can



from here:
http://www.off-roadweb.com/tech/0212or_steering_information/

Ok, that makes sense to me. Thanks.

 

[outlander]

you need to straighten the passenger side wheel.
Adjust the tie rod so the toe is correct on the drivers side wheel
Then use the collar at the top of the draglink to adjust the steering wheel position.
The collar at the top of the draglink will not affect the toe adjustment drastically. It should be a simple re adjustment on the tie rod to correct it.[/QUOTE]


So how do you measure the passenger wheel to make sure its straight without anything to base it on such as its relative position to the drivers wheel?

 

[Ray H]

you need to straighten the passenger side wheel.
Adjust the tie rod so the toe is correct on the drivers side wheel
Then use the collar at the top of the draglink to adjust the steering wheel position.
The collar at the top of the draglink will not affect the toe adjustment drastically. It should be a simple re adjustment on the tie rod to correct it.

So how do you measure the passenger wheel to make sure its straight without anything to base it on such as its relative position to the drivers wheel?[/QUOTE]

How do you know either of the wheels are straight. Its easy if you have an alignment rack. I dont have one. I measured off the rear tire.

 

[outlander]

Cool thanks...what do you use a 2x4 or some kind of flat edge held against the face of the rear tire to see if the front is true to the rear?

 

[Ray H]

I used a short piece of 2X4 and a lazer level.

 

[outlander]

Did that give you a fairly accurate alignment?
Wouldn't it be more accurate if the wheels were off at all four corners that way you could use the hubs face as a measurment point instead of the rim/tire?Its seems like fluctuations in side wall and rim trueness would give you false indications???escpecially on swampers,btw they were the reason that my driveway alignment turned out so bad.

I ask all these questions because I am 98% diy with the exceptions being gear set up and alignment.There has to be a way to inexspensively do an accurate alignment at home that is "close enough for government work",
yes I know I AM cheap!!

 

[Ray H]

Did that give you a fairly accurate alignment?
Wouldn't it be more accurate if the wheels were off at all four corners that way you could use the hubs face as a measurment point instead of the rim/tire?Its seems like fluctuations in side wall and rim trueness would give you false indications???escpecially on swampers!!!

It probably wouldve been more accurate using just the hubs but it worked out pretty good for me. the Jeep seems to handle and drive well. I cant say about tire wear yet.