Are Minitrucks Legal in US
This may seem a very confusing question as the laws in US vary from state to state. Almost all the websites which I referred to says that there is no specific state laws governing mini trucks. In this context it is better to follow the state Department of Motor Vehicle Site guidelines. In most states, the Department of Motor Vehicle will not register or title any Kei-class vehicle unless the applicant provides proof the vehicle has been brought into compliance with all applicable Federal Motor Vehicle Safety Standards (FMVSS) and U.S. Environmental Protection Agency (EPA) emission requirements. Moreover, all imported vehicles need to clear US Customs and comply with the safety and emissions standards. This implies that it is possible to register minitrucks for road use if these conditions are met and you should be able to legally drive your minitruck in the state.
What you have mentioned is true but these mini trucks are not to be driven on the state highways. EPA has stepped up enforcement against illegal mini trucks.