My 15 DRW RAM Crew has a 14K GVWR but the rear axle is rated for 9,750# and the front axle is 6,000#. My loaded front axle is under at 5,460# and so is the rear at 9,580#, total 15.040#. My GCVWR is 37,800# and my combined weight is 32,500#.
I am under on all ratings except for GVWR of 14K. The reason the truck is only rated at 14K is because of licensing, insurance and the fact that anything over that changes it to a Medium Duty rated truck as if it were a 4500. The new 13 and newer RAM 3500HD Dually's are a 4500 with a 3500 badge. TFL tested the 3500 RAM and 450 Ford side by side, they are both SAE rated.
Don't believe me just look under a 10-12 RAM then look under a 13-16 RAM there is no comparison!