If you use the coach often, you have no worries going five or six years from the date of installation. But if you are one of those RVers that will spend 500K for a coach and park it for six months at a time, THEN you better change them at three years. Tires do not show tire sun rot if you move your coach at least once a month and drive it some miles. But if you are in the south west part of the country with your coach in the summer months, the sun will rot the tires if they are not moved.
Don't worry! You will be OK.
