Classic Winnebagos & Vintage RVs

I had bought 6 Samson 8R-19.5 tires back in 2014 based on the recommendations of members here and also on other forums. They have held up quite well but when I had the front tires off yesterday I am starting to see the telltale cracking around the sidewalls that comes with sitting for long periods. I had been told the Samsons had additives added to their tire to prevent ozone deterioration due to the fact that Samsom make truck and trailer tires that tend to sit for very long periods. I am guessing that did not pertain to the 19.5 tires. As long as you are running them regularly like Kevin they are fine but I get out twice a year. I wanted to add this to the original report I did on the tires but I could not find it.