When buying tires, get to know (at least in the USA) of the DOT Date Code. On only ONE place on the tire, there's a four-digit code stamped into the sidewall at the end of another string of codes. It's WWYY where WW is Week and YY is Year. This tells you how old a tire is. Should be on all the tires on your coach.
1017 would be the Tenth Week of Year 17. A tire with that code would be made sometime around now, March 2017. Insist that each tire you buy is "Fresh." Discount Tire down the street from me called their warehouse, told them that, and they replied with the date codes they could send. I bought seven tires, all made within a few weeks of purchase date.