ST to LT

I've had Discount swap STs for LTs on our last 2 5ers and I couldn't be happier and less stressed after the luck I've had with STs in Az. The first ones were Dunlop Rover HTs... put a lot of trouble free miles on them before trading it. This one has Cooper HT3s... not very many miles but I have full confidence and Cooper recommended them. A friend had a freaky accident with his 5er that had a swivel tote on the back end. After that 5er rocked high enough to nearly flip on both side and came down hard enough to permanently reverse arch all 4 springs and buckle the frame, destroying the 5er, I wouldn't hesitate to buy those same Firestone LTs. Sorry, can't think of the name of that tire he had but there was NO detectable damage. I've had plenty of personal experience with extremely overloaded grain wagons, class 8s, and work service trucks when all there was available was 50-60s 2 ply car tires and the later P series and truck tires of the 50-70s era, before there were LTs and all the gov't regulations on everything imaginable. I now have 99% faith in any big name brand LT and 1% faith in any ST. I feel perfectly comfortable running LTs all the way up to their max weight rating and perfectly uncomfortable running an ST at 500 lbs under it's weight rating. Maybe it's just an Az. problem. Craig