I only have a 2006 Ford F-350 Crew Cab long bed Dually.... with a Talon Suspension system and Gale Banks Big Hoss Bundle... but I'm dragging a 24' Tag... A MotorTrac 4000 and it only has dual axles... And the tires are Hecho in Mexico... after I replaced the Hecho in Chinaco that I had put on to replace the brand new OEM versions that came on it. The Hecho in Chinaco BLEW on I 10 pulling out of Palm Springs... I replaced all 5 with the current tires once I hit Phoenix. I just don't think "trailer tires" are rated for high speed extended cruising...
If I had a gooseneck -- and triples.... I might creep up to 82 !!
LOL