I run some pretty heavy trailers. One truck is registered to 34K. I was doing a set of tires every year on my tandem duals. I switched to samson 14 ply and they have been fantastic. I have since bought 11 of them over the past 2 years. My dump trailer weighs 11k empty just as an example. Those have been money. If only I could get some 14 ply in a 17" rim for the truck now. I'm lucky to get 30k out of 80k michelins.