Lets try and make this more simple. The Arizona law says this extra tax and using the appropriate pump that collects that tax is required by “Use Class Vehicles.” Those vehicles are then described below and I included the Arizona definition of those vehicles:
Road Tractor, Truck Tractor, Truck, or Passenger Carrying Vehicle.
Arizona law then defines three of the four classes of vehicle listed:
28. "Road tractor" means a motor vehicle that is designed and used for drawing other vehicles and that is not constructed to carry either a load independently or any part of the weight of a vehicle or load so drawn.
56. "Truck" means a motor vehicle designed or used primarily for the carrying of property other than the effects of the driver or passengers and includes a motor vehicle to which has been added a box, a platform or other equipment for such carrying.
57. "Truck tractor" means a motor vehicle that is designed and used primarily for drawing other vehicles and that is not constructed to carry a load other than a part of the weight of the vehicle and load drawn.
What is missing in AZ law is a definition of “Passenger Carrying Vehicle.” Clearly a motorhome does not fit in any of the other three categories. So this law only applies to a motorhome if a motorhome is classified as a “Passenger Carrying Vehicle” under AZ law. But since AZ law (at least not that we have found yet) defines Passenger Carrying Vehicle lets look at Federal Transportation Law. Every single place I can find in Federal law, as well as every other state law (and even United Kingdom law) that mentions “Passenger-Carrying Vehicle” is referring to a vehicle that is used and designed specifically for carry passengers for hire.
There is absolutely no reason to use the term “Passenger Carrying Vehicle” unless you mean to refer to a vehicle such as a bus used primarily for carrying people. Otherwise you would just say Vehicle!
In fact this AZ law used to specifically refer to a Passenger Carrying Vehicle capable of carrying more than 20 people. So clearly the original definition was meant for a bus. I don't know why they removed the 20 person requirement, unless they simply removed it because they wanted to be consistent with the weight and axle requirement. Under the weight and axle rule it doesn't matter how many passengers it can carry, but only that is a passenger carrying vehicle.
