Sometimes, it is not in a fleet’s best interests to have a vehicle at a given GVWR. Changing the GVWR to a special value can be done, but the process is complicated.
The Fleet Manager's Guide to Comparing Fuel Economy
Vehicles 8,500-lbs. GVWR or more are exempt from federal fuel economy requirements, making it more challenging to project fuel economy for vehicles such as 3/4-and 1-ton pickups, vans, and medium-duty trucks.