Mike I run 26's but I know I can go to a 27 no problem at all. 493_John gave me a good pointer... a lot of dusters are not consistent side to side. Take a second and check yours. Does the tire fall in the same spot in the wheel well opening on both sides. On my car, the passenger tire is way closer to the rear of the opening then the drivers side. I also notice, the lower the front end the easier it is to get the taller tire in there