Wilson Pacesetter cover not working correctly

[Alagos]

Found on PC

Vehicle/Tool/Model/Object: Wilson Pacesetter
Issue: Back half of the trailer can be loaded with the cover closed
Single- or Multiplayer: tested in SP
Steps to reproduce: buy the Pacesetter and try to unload a seed pallet with the cover closed.
Does it happenyes/no on a standard map without mods: This happens on a clean save without mods!