That is wrong.Jeep GC is unibody, only body on frames are trucks
"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 8,500 pounds (3,860 kg) 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.” Light trucks includes vans, pickups, and sport utility vehicles.
The PT Cruiser was classified as a light truck"
en wikipedia org/wiki/Light_truck
Trucks are subject to different fuel economy and safety regulations than cars.
Please update your definition that at best is 50 years out of date and at worst has never been accurate.