Car pulling to the left when steering wheel is centered
 

Hey guys, I'm having trouble with my car pulling to the left when the wheel is center. I had probably 4-5 alignments done within 10 months. All alignments had about 2.5-3.0 negative camber in front with 0 toe with the rears being close to 2-2.5 negative camber with ~1/16 toe in (each side and total). Had one done few hours ago and it looked fine on paper, just when I started driving it goes pulling to the left with wheel in the center. Had one done last Friday and same results. Had the other 2-3 done earlier this year and noticed the same results as well. The steering wheel is centered when doing it. I did both the last alignments while the first couple was done by a known reputable shop. What I also noticed is that if I do turn the steering wheel a little bit to the right (off center), it does drive straight.

Side notes:
-One of the washers on the rear toe bolts was damaged from improper adjustment which I'm pretty sure it's causing my rear toe to slip out so I opted to replaced it with spc toe arms recently (if I'm correct, it was damage about 2 years ago from a new mechanic at a different shop who did my alignment, never went back).
-I also did have my passenger rear tire replaced on the same Friday.

There's your problem. Well, at lest one that I can see. New tire on one side vs. an old one will cause the lsd to kick in thus making it steer in that direction.

One thing you could do is swap the rear tires to the front. If the problem goes away, then you'll need the matching pair.

Another thing check tire pressures make sure they are the same.

I'll give that a try tmr but it was already having the issue prior to the new tire. If that fixes it, I will be shocked.

You should not have mismatched tires on the drive axle. If you replace one, you have to replace both unless the other is really new. Even slightly different wear will eventually damage the diff

When you get an alignment get .10 of toe in up front. That will help the car track straight.

I'm not sure about that. It is often suggested on these forums to have zero toe at the front and and small toe at the rear.

Does this happen on every road, or just sometimes? Find a nice flat smooth parking lot and try again to see if it's related to the roads, or actually a problem.

I have a few nearby roads that pull my car around, but it's fine 99% of the time.

Some toe in at the front will help the car be more stable at the expense of slightly increased tire wear and a lazier/more difficult turn in. Could be worth it if you do a lot of freeway miles and like a car that tracks super straight. The reason it's not recommended more is because... well this a sports car forum and it's counterproductive to why this car is compelling for many.

With regards to the OP, presuming it's not road dependant, either the shop is lazy and not centering your steering wheel, or they typically put some offset into the toe angles so the car tracks straight on freeways or crowned roads intentionally, reasonable for a commuter on those kinds of roads, annoying for a sports car. Loose parts would be inconsistent, bent parts would be compensated for and only come up as being problematic dynamically, not on a straight flat road.

Explicitly tell the shop what you want next time you drop it off, whether it's this one or a different one. They won't make a note of it and have the tech do anything different unless you explicitly point out the problem, especially if you return to this shop again.

Yes, they do. Prior to retiring my dad was a mechanic at a Pontiac dealer, specializing in front end work (including alignments). This is one of the things he always did.

I figured that it was mismatched tread that was causing the issue but none of my friends could have confirmed it that difference in tread will cause alignment issues. Just rotating the tires fixed about 95% of the pulling left situation. It still slightly pulls but not as much as before. Need to check other parts of the car to see if anything else is causing it to pull.

Yeah that's what I did to eliminate the fact that is was the roads. It was happening before I installed the toe arms, but I guess that broken toe washer was the main culprit before. It still slightly pulls to the left after the tire rotation but not as much. Right now I'm just trying to fix all the problems I am getting in terms of suspension.

It's not the shop issue. I personally did my own alignment as well (on an alignment machine of course) and it still pulls to the left. Just rotating tires front to back and back to front fixed most of the pulling left issue. I feel like there might be other things that can cause it that I should look for.