I upgraded the fronts on my Bus to get more weight carrying capacity and still keep a softer ride. To do that I also had to go to a wider wheel, but that was for weight considerations, not clearances. We're now running 295R80 22.5's on the drive and tag and 315R80 22.5 on the fronts. Since we go to out of the way places (Alaska 7 times) we also have a 295 mounted spare. With that setup I can change a front if we ever have a flat and limp it in to a location where I could get a proper tire, should that become necessary. The 315's clear the wheel wells fine, but I did have to move the entry steps as far forward as the mounting holes let me.