Abstract: A coupling for use between first and second vehicles has a series of sections joined in line by pivotal connections. One section is a draw bar anchored to the frame of the first vehicle, another is a tow unit connected by transverse pivots to the second vehicle. A first intermediate section has a pivoted connection with the draw bar section with the connection having a transverse pivot axis and a fifth wheel connection with a second intermediate section. The second intermediate section has a connection with the tow bar section that permits limited turning on a lengthwise axis between them and, accordingly permitting limited roll between the two vehicles when the coupling is in use. The coupling is described with particular reference to uses with first and second trailers.

Abstract: Trailers for use in hauling logs and adapted for use in tandem have fore and aft bunks each of which has a pair of horizontal members that are connected by a central pivot to the trailer and have vertical stakes at their outer ends. An air operated piston-cylinder unit is provided for each bunk with its rod connected by links to the members to enable them to be pivoted between a first position in which transversely aligned stakes are spaced apart a minimum distance to provide a minimum trailer width and a load-receiving position in which the distance between corresponding stakes is increased to establish a maximum trailer width.