PURPOSE: To hold a car in appropriate attitude even though the over-spring weight distribution of the car is changing, by correcting or updating the target static load at normal straight running on the basis of the load applied between over and under the spring sensed while the car is running.

CONSTITUTION: An actuator M1 is interposed between over and under the spring at each wheel of a car, and the load applied between them is adjusted in accordance with the supply/exhaust amount of working fluid. Under normal straight running, the working fluid in a specified amount for adjustment of the abovementioned load to the target static load is supplied and exhausted from a control means M2 to the actuator M1. In this arrangement the load applied between over and under the spring is sensed by a means M3. While the car is running, the target static load is corrected/updated by a means M4 on the basis of the load sensed by the means M3. Thereby the road surface turbulence to the car in running is shut off, and the car is held in appropriate attitude.