Sorry, I don't have a Toolcat, but did look up the tire specs. Looks like your machine is equipped with 27-10.5x15 6 ply tires. They may be kind of an odd size to find a tractor ag tread tire. Galaxy tire (http://www.galaxytire.com/pages/cat.asp) has their R4 tires (industrial) which is probably exactly what you already have. Have you asked your dealer about alternative tires? I would recommend a wider tire, but you may run into clearance problems, especially with the all-wheel steering feature.