A vehicle including an integral transaxle apparatus with axles, a driving hydrostatic transmission (HST), a steering HST, and a differential unit. Driving operating means for slanting operation of a first movable swash plate of the variable displacement driving hydraulic pump for switching the travelling direction between forward and backward and for changing the travelling speed, and steering operating means for slanting operation of a second movable swash plate of the variable displacement steering hydraulic pump so as to determine the leftward and rightward cornering angle are provided. The steering hydraulic motor has a third movable swash plate interlocking with the driving operating means so that the slanting direction of the third movable swash plate is changed according to the operation of the driving operating means, whereby the vehicle turns laterally in the same direction in response to the steering operating means whether the vehicle travels forward or backward.