Federal regulations define a light-duty truck to be any motor vehicle having a gross vehicle weight rating (curb weight plus payload) of no more than 8500 pounds which is “(1) Designed primarily for purposes of transportation of property or is a derivation of such a vehicle, or (2) Designed primarily for transportation of persons and has a capacity of more than 12 persons, or (3) Available with special features enabling off-street or off-highway operation and use.”