I have a fifth wheel with Goodyear G614 G rated tires. They still have very good tread and still look good but they were made in the 19th week of 2014. I read that you can go between 6 to ten years....
My 8 year old Michelin XPS Rib and Bridgestone Duravis 500 tires survived just over 900 miles of travel on America’s Interstate Highways and you probably realize those aren’t always the smoothest roads especially when KY warned of a Rough Road! Maybe real infrastructure investment will improve things...