This paper presents steering ability around curves of the proposed self steering truck with asymmetrical suspension and independently rotating wheels in the trailing axle for rail vehicles. Using a simple linear truck model theoretical analysis was made and introduced the condition for wheel conicity and primary stiffness to improve the steering performance comparing with conventional trucks with normal rigid wheelsets. The steering ability of the proposed truck is examined using test stand which can simulate curving condition and lateral force and truck behaviors are measured. These experimental results are agreed with theoretical prediction and numerical simulations. It was found from these experiments and theoretical calculations that the proposed steering truck has better curving performance especially in very tight curve with flange contact than conventional trucks.