The tires that come on that tractor tend to get hard and the rubber slicker with use. Make sure you are not inflating the tires to what the sidewall says for max. Too many folks do that, but that number is to specify what the maximum pressure should be for the heaviest use that tire will ever see on any machine. About 10 psi in them is right. I maintained my dad's for him before he passed on, and have mowed quite a bit on one. That tractor also has a very tight turn radius, and that can actually be a problem unless you start slowing down while turning, because even when the tires are new, the machine will slide with full wheel lock in either direction.