New tires for my 16K fifth wheel

A lot depends on the kind of traveling you do: short distances several times a year, full timing, long trips several times a year. Personally if the tread is good and they look good, I would run them another year or so. I have a little over 6 years on the Sailuns I'm running and will probably replace them next year if I have a long trip scheduled.

I don't think you can do better than the Sailun S637 tire for trailer use. You can certainly pay more, and they are made in China, but if you want a tire that you can depend on, the Sailun is it.