I have no doubts that if Ram wanted to, they could raise the diesel 2500's GVWR to 11,500 lbs without needing to even touch the truck. I am not as confident about the Ford. The suspension is not tuned for a certain GVWR. If that were the case, then the 2500 diesel GAWR's would be a lot lower. The GAWR is the lowest rated of the axle system which is the axle, brakes, wheels and suspension. My 2014 2500 has a front GAWR of 6,000 lbs and a rear GAWR of 6,500 lbs with a GVWR of 10,000 lbs. The 3500 of the same year has a front GAWR of 6,000 lbs and a rear GAWR of 7,000 lbs with a total GVWR of 11,700 lbs. They both have exact same fron axle. The 11.5' AAM axles in the rear of both trucks is rated at 10,000 lbs, but the suspension of the 2500 has a lower capacity of 500 lbs even though the difference in total GVWR is 1,700 lbs. This is due to the max GVWR allowable for a class 2B truck. What GM did is moved this 2500 truck from Class 2B which has a max GVWR of 10k to a Class 3 which has a GVWR between 10,001-14,000 GVWR. This is good for non-fleet customers as you say, but not for many commercial fleet customers. There is nothing set in stone saying that manufacturer has to put a 2500 in class 2B. In fact all SRW 3500 trucks were in class 2B just like the 2500's up until 2006.