The TPMS won't be bothered by a larger tire size. It measures pressure, not the volume of air. As far as tire size, you know for sure a 255 will fit the wheel well, but the question is what size should you put on a certain rim width. You could go 225-55 or even 235-45 w/o much of a problem. Those sizes should be close to the same diameter so your speedometer won't be off. You can go to www.tirerack.com and that will show you your plus size options that will fit.