I just recently found this site and have been reading lots. My problem is I have an old AR that needs a new rear tire. Size is 13-26. Anybody know what that turns into with todays sizes? I was told 13.6-26 and was also told 14.9-26. I don't want the tires to be too small for the tractor and don't want to spend that kind of money and not like it. Thanks for any input.