If I recall right, it's based on how much you want to reg the truck for and that will determine if it's a commercial or pass plate. F150's can be either. Here near Syracuse, there is a area that's off limits to trucks w/ comm plates and that incl pic-ups. YET any hiway or public works truck can use it and have the exact same truck (I know cuz I've seen it). DMV doesn't need to know if you have a 5th wheel hitch in truck or not. Going back to what you reg it at, a few years back when I bought a truck, I was asked by dealer how much weight I wanted it at. I asked why and the reply was, it makes a diff on how much you pay. Plus, tho they didn't say it, I believe it also played into what type of plate you got.
In the end here tho, go and talk to DMV in person and ask just to CYA. Ask if it's based on what truck weighs from factory (title), weight class (1/2.3/4 or 1 ton). Here's the BIG downside IF you reg truck in such a fashion to obtain pass plates. Should you get a RV that truck can tow w/ ease and your considerably "overweight" based on reg class, and you get into a wreck w/ another vehicle, YOU CAN be SOL as they will have your behind. Based on my last sentence, I've always reg for max truck capacity (8800, 11,500 or 13+), and that puts me into comm plate territory. It sux to some extent, but the reg fees for pick-ups in NY really are not that bad when you compare them to other states. So good and bad.
