Welcome to the forum.
It's easy to determine your
Tire Age.
Generally, RVers replace their tires at 7 years. RV tires usually age out before they wear out.
Some use Michelin tires. I like Hankook tires, they're a good product and less expensive than Michelin.
You may get more responses if you turn your caps off. Most consider it shouting. And, it's easier to read for most people when typed in lower case.
There is a lot of information available on the forum. Just ask, someone will have an answer.
Enjoy your travels.