A steering system (10) for a vehicle includes at least one wheel (14) that
pivots to define a steering angle (20), and a steering lock (12) that
limits an input to the steering angle (20) from an operator to a selected
maximum value. The steering system (10) also includes a motor operatively
connected to the wheel (14) that augments the input to the steering angle
(20) from the operator, and a controller (42) operatively connected to
the motor and adjusting the augmentation of the input to the steering to
provide a maximum angle from the operator based upon at least one
operating parameter, that includes the size of the wheel, thereby
allowing the wheel (14) to pivot to a steering angle (20) based on the
operating parameter that exceeds the steering angle (20) corresponding to
the maximum allowable value as defined by the operator input.