Agreed. Note the "®" (e.g. registered trademark) that follows the first two components of the name, Defender® and LTX® (e.g., MICHELIN® Defender® LTX® M/S). So, the LTX in this tire name does not mean it's a Light Truck tire. It's simply a marketing moniker, like Michelin®.
So, until we get to the Defender tire in this size, "LT225/75R16/E 115/112R" we are talking about a Load Range D tire in the P-metric family. Yes the 15" model has an XL (extra load) capacity, but it's not a Light Truck tire. So, if I was gonna use the 15" model of this tire, I'd have to de-rate it by 10% to figure out an acceptable load, per lots of threads here about de-rating load capacities when the tire isn't a Light Truck tire or an ST tire. Doesn't mean I couldn't use the LTX tire on my trailer if I wanted to, but I better do the math first and make sure everything is cool. After that, all I have to do is find a dealer who will put them on for me. I failed at the latter, and so moved up to 16" wheels and LT tires.
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