Abstract: The load of a trailer is applied to lower members of shackles that have upper members rigidly attached to axle housings of tandem axle assemblies. Linkages and levers are connected between a lower pivotal member of a swivel assembly supporting the load and the ends of the axle assemblies. Rotation of the main frame of the trailer on the swivel arrangement during turning actuates the linkages and levers for displacing both axle assemblies in the desired directions to facilitate turning. The upper and lower members of each shackle move in a relative arcuate direction for raising the load slightly as the angle of turning is increased. The force of the load tends to return the shackles and the axle assemblies to the normal positions for straight travel and thereby contributes to stability.