Hey guys, a few weeks ago I installed saleen shocks, struts and springs and waited on an alignment for about a month until I got my new tires. The car drove relatively straight, not much pull either way but you could tell the alignment was off a shade.

Well, I had new tires put on Thursday and went to get an alignment yesterday. I wanted to go to NTB because they've worked on both of my friends lowered GTs but the wait was too long so I went to Sears Automotive.

They got me in an out real quick but when I took the car out on the highway it pulled to the left. It didn't pull hard, but was a slow consistent pull. When I braked hard, it pulls to the left as well.

I went back and talked to the tech, he told me that the caster was off and that our cars don't have the ability to adjust that. He said there is nothing else he could do, but he said one of the tires might be improperly balanced. He recommended that I swap the drivers side front for the drivers side rear and see if that solved it. If so, then that means the front tire isn't balanced properly.

He said if it still pulls to the left, then I should get some caster bolts and they can make the needed adjustments.

He gave me my specs and based on the caster specs, they look good and within range.

Camber Front Left:
Current: -1.0
Before: -1.2

Camber Front Right:
Current: -1.3
Before: -1.1

Caster Front Left:
Current: 7.1
Before: 7.1

Caster Front Right:
Current: 7.2
Before: 7.2

Toe Front Left:
Current: 0.04
Before: -0.17

Toe Front Right:
Current: 0.06
Before: -0.12

I have no idea what all this means and have no idea if he's being straight with me. I was hoping you all could provide some insight here. I have $750 worth of brand new tires here and I'm hesitant to drive on them because I don't want to prematurely wear them down.

Any help or advice you guys could provide would be much appreciated.

Thanks!

 

No such things as castor bolts for the S197 that I am aware of ... he probably meant camber bolts, which do not affect castor, only camber. The only way that I know to effectively adjust castor is by using Maximum Motorsports camber/castor plates.

However, all your numbers look to be within spec.

 

I'm looking at the 'cross' values, and they indicate that drifting toward the left is possible.

Cross-caster didn't change, but was always a tiny bit towards keeping the car out of the gutter on a crowned road.

Cross camber did change, from 0.1° more negative on the left side to 0.3° more negative on the right. That will change a tendency for the car to push to the right (before, which tended to balance the cross-caster effect) to a tendency to push the car left (current, which is adding to the cross-caster effect). IMO, an 0.4° change in front wheel cross is more than enough to notice. I'd rather see your RF camber where it was before (-1.1°).

I don't agree about an unbalanced tire being the problem. A tire with a structural carcass defect, maybe. You might expect a tire with a bad carcass to also be out of balance, but that's not necessarily the case in all situations.


With respect to the specific values - the factory preferred caster setting is 7.1°, with a range of 0.5° either way from there. You're fine here.

Preferred factory camber is -0.75°, with a tolerance of at least 0.5° either way (any +value or more than -1.50 represent the 'reset' points, at least for cars subject only to "normal driving"). You're still OK, especially since your (current) toe is minimal but still 'toe-in'.

FWIW, my car came with about -1.2° camber as delivered (it's a built-to-order car). I drive fairly hard around corners most of the time, and I'm not afraid to use the brakes hard either. Anyway, in the first 13,500 miles I still hadn't worn a full 1/32" off the OE 18" BFG's (400 treadwear). My point being that being up around -1.25° is not a "tire-eater" setting if the rest is OK.


Norm

 

They do have adj caster bolts, and requires grinding a little. I saw on another forum a part # and directions to do it. But looking at your info, caster doesn't appear to be your problem.

 

It may also be a problem with the tire! Not a balancing problem though!

 

There are castor bolts to correct that but you do not need them. I agree with Norm. Your current alignment specs are all within factory spec. For the street you are not going to want more then 7 degrees of castor. It looks like your toe is set out which while driving will increase, could casue the car to "walk" or even get squirrly under braking, it will definitly walk on a crowned road service. I have my camber at -2.0 and my toe set to zero. I do not have any tire wear issues at all but can get squirrly under hard braking, it is nothing dangerous but it is something that I know can happen so I am prepared for it.

 

did u put a new panhard bar on your car when u lowered it? because that would make the car pull in one direction.

 

Nope. Went from total toe being 'out' to 'in'. Got a little better for stability, might have given up a little cornering behavior or "feel" up around the limit.

The sign convention for toe has always had me chasing down a reference just to make sure I've got it right. I think I've finally managed to pound it through my thick skull that + = in, but anyway here's what the Hunter undercar (shop alignment rack people) have to say about it.

Linky

Norm

 

Thanks for all the feedback guys. I'm taking the car back to Discount Tire today to have them rotate the tires to see if that cures the problem. If so, then it's most likely a tire issue. If not, then I'm going to a specialist alignment shop to have them take a look.

 

Yes thank you for correcting me Norm. I really don't even know the signs, I have always checked my toe with a tape measure and plates. So degrees really has no value to me...