An adjuster device includes (a) a shaft held by a vehicle body; (b) an arm extending from the shaft in a direction intersecting an axial direction of the shaft; (c) an actuator causing one of rotation of the shaft and axial movement of the shaft in the axial direction; and (d) a motion converter converting the one of the rotation of the shaft and the axial movement of the shaft, into the other of the rotation of the shaft and the axial movement of the shaft. The arm is connected at a distal end portion thereof to one of at least one suspension arm, so as to enable the rotation of the shaft to cause change in a vertical distance between a wheel and the vehicle body. The shaft is connected to one of the at least one suspension arm or to an axle carrier, so as to enable the axial movement of the shaft to cause change in an alignment of the wheel. Also disclosed is an adjusting system including the adjuster device.