[Baddawg53]

I'm switching to a square 18 inch wheel setup and have read about traction control issues when you run a square setup. My question is, is it possible to reprogram the stabilitrak/ traction control system to look for the new tire size? Will calibrating the speedo with hp tuners have any affect on the traction control working properly? Will running with the traction control off stop the car from trying to correct for the incorrect tire sizes?

I am really unfamiliar with exactly how the system works, so any input would be appreciated.

[JitteryJoe]

I'm by no means an expert but I think you only run into issues when the tire diameter's are >~3%. I think the TC and stability just look for differences in wheel speed between the wheels via the ABS sensors. So with a square setup this is almost never the case unless you're running some sort of crazy no-rotatable "square" setup where the front or rear tires are taller for no good reason.

[Baddawg53]

Yea I've read the 3% number before, but I thought that it was 3% of the stock tires, which are staggered. I've gotten stabilitrak warning lights since I switched from the SS tires to the 1LE size tires. I can't imagine it getting better with a square setup. Maybe it'll be fine, or maybe I'll have to call a dealership to see if they are able to reprogram it.

[ctrlz]

Originally Posted by JitteryJoe

I'm by no means an expert but I think you only run into issues when the tire diameter's are >~3%. I think the TC and stability just look for differences in wheel speed between the wheels via the ABS sensors.

Close enough to expert for me!
OP should post tire sizes for front and rear. Air pressure can also be a factor, as the car only cares about the diameter it detects, which can change with tire pressure.

[Alpha1BC]

I've run 305/30R19 square on my SS 1LE without any warnings or codes. I'm also not sure why you got warnings on 1LE sizes as I've run SS 1LE wheels/tires on an SS before also without issue, so there could be something else going on with your car specifically. There's not really any reprogramming that a dealer can do that I'm aware of, either.

I don't know for sure if 3% is the threshold as I thought it was higher than that, but there is definitely a threshold the the front vs. rear wheels need to be within relative to one another. What are the wheel/tire dimensions you want to go to?

[Baddawg53]

I'm going 315/30/18 with that apex group buy.

The car drives normal now with the 1le tires, doesn't feel like it's trying to limit it at all, just the occasional stabilitrak warning. I'll have to see what OnStar can tell me about that. Hopefully it'll be a non issue for me.

[lt4camaro]

3% + or - of tire diameter is correct. I am putting a 27 inch tire on the rear of my car which has a 27.7 inch tall factory tire. That is a 2.6% difference and it works fine.