When imported, the car has to become road approved by an authority, like e.g. TÜV or Dekra in Germany, to ensure that it's conforming with the general standards for road vehicles (which are less strict than when a brand would be trying to get a general certification of that model).
If by construction, the car is allowed to have a maximum total mass of e.g. 4 tons, as e.g. it's stated in its US documents, it's possible to have only 3,49 tons written into the German/European documents and thus, have it classified as a 'car'.
However, if you get caught with that vehicle loaded with more than what is allowed to stay below 3,49 tons, it's considered a) overloaded, an offence under public order, and b) driving without proper driver's licence, which can be a criminal offence.