Tire life expectancy

You asked a very interesting question! Tire life depends on many factors. I suggest that you visit Michelin Tires website and go to there Quality Tire Care section to learn how to properly maintain a motorhome tire. One mistake that you already made is using petroleum products on your tire. The Michelin website will explain to you how this will effect the life of your tire and how petroleum products brake down the rubber of a tire. Michelin says on there Quality Tire Care Website, to clean your tires with warm soapy water and a scrub brush only! I've done everything on tire maintenance that Michelin Tires Website said to do and, I was able to get 10 years out of my last set of Michelin Tires. I just had a new set of Michelin Tires put on 2 weeks ago and, I expect to get another 10 years on my new tires. I also had a tire expert inspect my tires every year after the tires reached 5 years of age, and I ran for ten years a higher tire air pressure 100 lbs. then Michelin recommended they recommended 90 lbs. I'm a retired trucker and I ran 100 lbs. on my semi tires with success so I tried it on my motorhome and it ended up being a success for me. And someone already mentioned Motorhome Magazine they had an outstanding article on Michelin Motorhome tires in there August 2010 issue. Good Luck and Happy Trails.