A question about tires on three axle fifth whl trailers.

15K across three axles in a TH is much different than a fiver with only 2 axles. ST tires with heavy weight loads seems to be the ones that fail the most. Heck 15k divided by 6 is only 2500 lbs each tire. Now spread say 13K divided by 4 tires you get 3250 lbs.
The bigger fivers will carry much more weight per wheel than a TH with six wheels. Most of the newer big fivers now have a 17.5 option or a G rated Goodyear tire.
Edit wheel size from 19.5 to 17.5 :W