Tire size fitment is going to entirely depend on what wheels you're using, specifically their widths, backspacing, and offset. In theory, since the ICON 2.5s can add up to 3" of height vs. the Fox 2.5s 2" of height, you would be able to go slightly bigger with the ICONs. The ICON rear shocks can handle up to a 3" rear block, so you have a few options. Your best bet would be to call us directly at 623-434-5277 so we can get more specific about your wheels and tires.