Tireman, thanks again. I've noticed front tires turn differently, never knew why. One of the reasons ST tires were created in the 1970's, as I understand it, was that the relatively new radials had weak sidewalls, people didn't want bias ply tires anymore because radials were better in most ways and so a radial with a stronger sidewall was development for trailer use.
But, the ST's available are just not very good tires except perhaps for someone who travels very little and whose ST's age out before they have more than a few thousand miles on them—why spend twice (or more) as much for a good quality LT? For the rest of us, a different answer though. The Michelin Rib tire may be a better solution than the LTX because the Rib has steel cord in the sidewall. The Rib is designed for delivery trucks used in town and is made to be recapped one or more times, but may be a good choice for trailers. Hope I got that right.