Originally Posted by whippersnapper02
I never had a problem with my other truck. I had it aligned with 29s and went up to 31s and the alignment was still good. Maybe it was just within spec?
Possibly. If you move to another tire size that the manufacturer offers as a factory option, then the mfg specs will work out for you.
The problem is when you go larger or smaller, and mainly has to do with suspension deformation at speed, and deformation of the tire when turning. A larger tire (and more aggressive tread) tends to toe out more and camber up less when driving at freeway speeds. Therefore, mfg specs may result in abnormal wear.
Essentially, the only way to deal with this is to dial it in over about 6 months. You need an alignment guy that knows his shit, or doesn't mind taking orders from you. It also requires sacrificing a little tire tread (very little). Basically, you go to 0/0/whatever caster feels right for you, put about 500 to 1000 miles on the truck, then read the tread. Based on wear, adjust your alignment. Repeat until you're getting even wear and the vehicle drives well. Then save those alignment numbers for as long as you run that setup on the vehicle.
My truck seems to have found the sweet spot at .02 toe, .4 camber, and caster in the high 2s...say 2.8 to 3. But that's my setup. Different spring rates, tire widths, and driving demands will alter things. And again, this only applicable when drifting outside manufacturer offered tire sizes.