That's kinda what I have in Gladys. It all has to do with the vehicle GVWR. With Fords, they aren't "just" an F250, for example. On the VIN it starts with "F250" but on the data plate it might be different. Mine for example, begins with "F253" because it is a heavy duty F250. 8100 GVWR. That's more than some F350s of the same year. Essentially, Gladys is a 3/4 ton truck on a one ton chassis. She also has the Camper Special package, which is completely separate from the heavy duty option. Gladys got the double whammy from Ford. LOL The F series in the 250 line goes all the way to F259, which is a heavy duty 4x4 F250. The GVWR increases with each increment. GM and Chrysler had similar.