exploding tire

I'm on the 2nd year of my third set of tires. All previous 8 tires failed. The first tire went in the fall the 2nd year we had the trailer with < 1,000 miles on them. It failed completely, but did no damage. About 60 miles from home and NOT overloaded by any stretch. The other 3 failed the next year but I was able to catch them starting to separate before they actually did any damage. I kept the one replacement tire from the year before as a 2nd spare. On the 2nd set, I jumped up to E-range tires and had them on from 07 to 12. Yes, a long time for ST's, but I baby'd hell out of them the last 2 years. Total of under 5 years' service from install to replacement. They =all= were showing tread separation, with one tire so rounded that it had started rubbing the top of the wheel well slightly when going over bumps. I wanted to go with Maxxis at that time, but Discount did not have any in ready stock and I need them on the next day, so went with the Carlisles as the best of a bad choice. So far, the jury's still out on them, though several people I know that are using them, seem to be having success.

Lyle