Door gap seals and seal assemblies for over road trailers and other over road cargo carriers are disclosed herein. An over road trailer configured in accordance with one embodiment of the invention includes a door rotatably mounted to a container body proximate an opening. The door moves between a closed position in which the door at least partially covers the opening, and an open position in which the door is spaced apart from the opening to form a gap therebetween. The over road trailer further includes a seal attached to at least one of the door and the container body. The seal is at least partially compressed and/or deflected between the door and the container body to seal the gap when the door is in the open position.