Our teardrop trailer is 1600# and there have been a number of stories on the Teardrop & Tiny Travel Trailer forum of catastrophic tire failures with serious damage from ST tires that are under loaded. All of these were Goodyear Marathon all young enough. Finding ST tires not made in China proved to be impossible (including Goodyear), If my memory serves me (always some what in doubt)some Carlyle are made in China some not.
I replaced my Marathons before a 3000 mile trip last year with Micheline Harmony passenger car tires which had a weight rating of about 1600# each.
Tire information (not easy to use but complete)http://www.nhtsa.gov/apps/manufacturer/index.htm
If you have a failure report it https://www-odi.nhtsa.dot.gov/ivoq