You can way overload about any of them for low speed and short distances. What happens, though, when you hit 70 on the freeway with your bumper 6" off the ground?
I spend 18 years working for a large LTL trucking co. I never heard how it happened, but we had a set of triples go across a scale somewhere in NM. The DOT boys told the driver to go around and drive across the scales again...sloooowly. They couldn't believe what they found. A 28' pup trailer on a single axle tractor is maxed at about 25k if loaded right. The other 2 trailers have to be lighter to make gross wt. The front trailer was loaded with pennies from a mint and some idiot had loaded 90K on it. The driver couldn't figure out that something was wrong with his rig other than he was moving a bit slow and sluggish.
They had to park the trailer where it was and send a crew out to transfer the load to other trailers.
