Originally Posted by DonGott
How often should the tires be changed out?
I don't know what brand your tires are, but Michelin has some good reference material on their web page here
The RV Tire Guide has photos showing examples of tread wear and cracking.
The Service Life Bulletin says tires should be inspected by a specialist starting at 5 years. It also says most tires will have been replaced by 10 years of age; but if not, they should be replaced at 10 years no matter how good they look.