A system for automatically coupling the air and electrical lines of a tractor to a trailer. A trailer coupling head is mounted to the trailer and carries air line and electrical connectors. A fifth wheel coupling height control system is configured to automatically control the height of the tractors fifth wheel coupling, to control the height of the trailer coupling head. A tractor coupling head carries air line and electrical connectors that are configured to be operably coupled to the mating connectors of the trailer coupling head. A tractor coupling head carrier removably carries the tractor coupling head. A tractor coupling head carrier control system moves the tractor coupling head carrier toward and away from the trailer coupling head along a longitudinal axis. The tractor coupling head can be clamped to and carried by the tractor coupling head carrier or the tractor coupling head can be clamped to the trailer coupling head.

A fifth wheel includes a fifth wheel plate, a plug, a drive, and a guide arrangement for the plug, wherein the fifth wheel plate has a semi-trailer surface that has an outwardly pointing normal, that is parallel to a vertical direction wherein the fifth wheel plate has an insertion opening that extends in an insertion direction, wherein the plug is displaceable by the drive from a first, in particular retracted, position into a second position, in particular an extended position, wherein the plug is guided from the first position into the second position and/or from the second position into the first position by the guide arrangement, wherein an offset in the vertical direction and in the insertion direction is present between the first position and the second position.