I was told by a factory tech that when you go with a taller wheel/tire, you may mess up the ABS calculations. I understand the +1, +2, etc concept. But many times, when you do the math, you could actaully be 1" taller (or shorter) overall. I understand the effects on the speedo/odo, but what about ABS?

What does HT.com say?

 

It doesn't affect ABS.

It may affect traction control, which depends on the difference in diameter (if any) between front tire size and rear tire size.