Abstract: An improved rail car moving vehicle adapted for travel alternately in one mode on rail wheels on a railway track and in an off-track mode on ground wheels, with weight transfer capabilities from a coupled railway car when in the on-rail mode, and characterized by improvements, including: a tricycle configuration of ground wheels provided by a pair of non-steerable, closely-spaced rear road wheels adapted to have frictional driving engagement with the driven axle of a rail wheel set and relatively widely-spaced steerable front ground wheels; a frame design that provides ample strength with respect to a bending or vertical load while having torsional rigidity not sufficient to normally cause one of the rail wheels to lift off from the track more than the radial dimension of its flange; a rear coupler assembly including a coupler carrier independently hinged to the vehicle frame for supporting a laterally swinging coupler independently pivoted to the frame at the inner end of the coupler arm; a pair of steerable