I just got back to KY from FL with my Jayco 1207. On the way down we blew both trailer tires. These were 3 year old Kumho 857 tires in the 195R14C size. They were not overloaded (only carrying a little more than half their capacity), no signs of dry rot, not under inflated, and only traveling 65 MPH (these tires are rated for 99 MPH). I had checked them a couple of times and they were never hot. The first tire blew but did not come apart. We pulled over and put on the spare. About 15 miles later the other one blew. The second tire had 3/4 of the tread come loose. The flopping tread did minor damage to the wheel well. Fortunately my dad was behind us and his spare fit my trailer. I replaced both tires with Goodyear Marathon radials from WalMart (205/75R14 LRC). We will see how they hold up. It just seems quite strange to me for two perfectly good tires running well within their capacity to blow at the same time.