I just bought new tires for my enclosed trailer that is typically loaded 6-8K lbs. I went up to LRE ST225/75R15 tires from LRD but also upgraded the rims at the same time. I didn't have any tire failures, but two are plugged, the tread was getting thin and I wanted new shoes on before we take a coming high mileage trip. I felt the cost was minimal to go from 8PR tire to 10 PR and should give me better wear and puncture resistance. I found I could order tires mounted on new rims shipped to my door for almost as much as just buying tires locally and having them mounted on my current rims because of the taxes and tire disposal fees. I will sell off the old set on Craigslist and end up at the same or less price as local but have new rims AND tires instead of just tires.