Every semi-truck or tractor-trailer depends on one small piece of equipment for its connection. It’s called the King Pin. This is a pin which connects the trailer to the ‘fifth-wheel’. The receiving piece on the truck is is a horse-shoe shaped platform attached to the tractor. It’s the pivot point between the two units and receives a great deal of wear and tear. Eventually, king pin repair or replacement becomes necessary on all working rigs.read more