The following definitions apply for estimating the capacity of a supply tank in diesel-powered vehicles:

(1) "Automobile" is a self-propelled passenger vehicle that usually has four wheels and an internal combustion engine and is not a pick-up truck or truck.  This vehicle is commonly referred to as a car, motor vehicle or automobile.

(2) "Combination" is a motor vehicle used, designed, or maintained for transportation of persons or property and has two or more axles whose gross weight exceeds 46,000 pounds or a combination of vehicles whose combined licensed weight exceeds 46,000 pounds.

(3) "Pick-up truck" is a vehicle licensed under a flat gross vehicle weight (GVW) fee and has a manufacturer's rated capacity of 1/4 ton, 1/2 ton, 3/4 ton or one ton.  This vehicle, regardless of how it is registered and plated, is also commonly known as a pick-up truck, van or sport utility vehicle.

(4) "Truck" is a vehicle licensed under graduating gross vehicle weight (GVW) fees and has a manufacturer's rated capacity exceeding one ton, but not exceeding 46,000 pounds.