Tires age out before they wear out !

5 years is the timeframe. Certainly heavy travel wear is always to be monitored.

If the RV is sitting at home or a seasonal park the tires are degrading,

UV light from sunlight , rain, mud and frozen ground seriously affects tires.

If you're going to make a move after being in one place for an extended period of time. Replace Tires , inspect brakes , repack bearings.

A blow out on a highway can be disastrous.

Every trip. Check tire pressure, look for cuts.

If you need a tire service roadside .... one tire could cost as much as four.