Thanks all for the very informative discussion.
From what I'm reading here, there is still confusion about the tonnage labels given to trucks. The manufacturers seem to be covering their rear ends by not using those labels. Some say the "older" trucks can haul more, some say the "newer" trucks can haul more. And "it depends" seems to be about the sum of it.....depends on axle rating, drive line, brakes, etc.
I wonder just how much
FoS "factor of safety" is incorporated into the GVWR of a truck by the manufacturers. We'll never know unless someone incrementally loads up a truck until it fails. Or would that truck fail catastrophically?
....or just have a wheel bearing go bad?
Inquiring minds want to know......