I changed mine to Michellin XPS Ribs, LT 235/85R 16. The Michellins are 1.2" larger in diameter than the ST's, so essentially makes the space between tires 1.2" closer than it is with the ST's. My middle axle is closer to the back axle than the front axle (why, I do not know) and there is only abou 1." clearance. I have towed it for 1600 miles like that with no issues. I'm not real happy about it, but I have a much better tire now, and it appears to be working. My next step is to try to get the manuf. to have the axles spaced properly, since they are not symetrical, and are too close together to start with.