Kingpin Definition:
A kingpin is a coupling mechanism with a large metal pin connecting a semi-truck with a trailer. It is attached to the fifth wheel hitch during the hauling process to ensure secure attachment.
The kingpin's primary work is to connect a semi-truck with a trailer when hauling. It also helps steer and handle the coupled rigs and keep the semi-truck and the trailer together. It helps securely attach a container to the chassis, providing stability and safe handling.