There is ample information on ST tires on this site, I have read all of it. I too blew out a china bomb within 1800 miles, Im in a RV park right now in New Mexico, there have been at least 3 rigs that have pulled in that have had at least one blowout one guy had two. The damage is incredible. The arguments on this website will range from a guy that has run chinese ST tires and got a million miles out of his last set, and is now on his second set he loves them so much, to guys that refuse to accept that you can run LT tires on trailers. Fact is that you have 2 choices at this point if you want to haul at least 65 MPH and haul a decent size 5th wheel on a 16 inch rim (check rim for 110 PSI and 3750 rating).
http://www.goodyearrvtires.com/tire-selector.aspx The Goodyear G614, it the optional tire for many heartlands. IF you did not ask for them then you did not get them.
The other option is the Goodyear G114 17.5 in rim. This will eliminate all load induced failures, and will allow you to exceed the 65 mph limitation to 75, not that you would really want to. ST tires come apart and are good for little more than landscaping company trailers.
I took my remaining tires and rims off and sold them to a landscaping company, I bought 17.5 in HiSpec mod 03 rims with G114s. My trailer handles better and I did not have a worry in the world while on this trip. You might have to dig deep to buy them but the question is "did you buy your rig to sit around a fret because some chinese tire tore the side of your rig out" or "Did you buy your rig to get to the beach, or mountains, to enjoy that oh so rare 3 to 10 days" IF you bought it to fret, then make sure you buy ST tires, If you bought it to enjoy then put some real tires on it. good luck.
BTW, we cause them too, its not just the ST tire that is the problem, its us. We forget what we did to them the last time we ran them, we forget that 180 degree tight turn that was rolling the tires off the rim, we forget what we do to them. I asked one blowout victim what pressure he was running, he told me 70 LBS, I told him he should run the max on the side of the tire which was 80, he said it seemed like it was too much pressure so he ran 70 psi. It is not entirely the tire, it is us too. But between failures and abuse there are a lot of ST tire treads laying alongside the road this 4th of July weekend. I saw a large boat yesterday with a blown ST tire.
Learn everything you can about tires, then get what you need, then make sure that you follow all pressure recommendations at all times.
The max load rating of a LT v ST is vastly different. The reason why is that LT load rating are calculated using a different set of criteria involving passenger vehicles. This demands a "service factor" where a ST tire does not come close to meeting construction and real load rating of a lt. But the sidewall will say that the ST will carry more. I call bull hockey. ST? don't buy em.
I recently took a long trip of about 3800 miles with my Sundance 5th wheel camper which is less than a year old. During that trip I blew out 3 of my original tires and also had to change the fourth tire because of a cut in the tire. After the first blow out a man approached me right after entering the campground we were staying at and asked if we had a blow out on the way up. I told him yes, and he explained that the reason for the blow out was that the tires that are put on the campers are not heavy enough to carry the weight of the camper with the slides and all of the equipment you have in the camper. He told me that he had gone through 2 complete sets of tires since he bought his camper. He finally did a little research and went to a G load tire which can carry a lot more weight than the E load tires on the camper. I need some advice on this problem. I inflated the tires with 75 lbs and they are rated for a maximum of 80 lbs. I have read that under inflation can cause a tire to fail. What is considered under inflation and how much weight can the tires that are put on the campers handle.