Suggest RV and trailer owners with Goodyear Marathon and/or Hi-Run tires check them closely. I had purchased a new set of each brand (235/80 R16 Load Range E) for my two axle 5th wheel, and had one of each brand mounted on same side. I prepared for a trip from TX to PA - at that time tires were less than two years old, had less than 2000 miles on them, tire pressure at start 75psi, and speeds not over 65mph. On the trip, at approximately 900 miles one of the Goodyear tires blew - steel belt separated, tread came off, and causing significant damage to the RV skin. I thought I must have run over something causing the blowout. Changed the tire and continued on. At approximately 100 miles down the road the second Goodyear blew. This tire came apart identical to the first one. I pulled into a truck/tire shop and had them assess the situation. They had no clue why the tires came apart in that manner. While replacing the two blown tires they checked the Hi-Run tires. They found that both of the treads were bowed and the steel belts were beginning to separate (several ends of steel belt strands had penetrated the tread). There was no unusual wear on the tread (which would lend itself to an alignment problem), and the trailer weight was well below the tire rating. I had the shop replace both those tires as well, and continued on. This event highlighted to me, even though you feel comfortable with your in-depth pre-trip inspection, it's vital to do cursory looks at critical points while traveling. On a side note, both the Marathon and Hi-Run tires were made in China, and if your tire is bowed and you're going to run your hand over the tread in an attempt to see if any wire is protruding, suggest you wear a glove.