Abstract: A self-pumping strut comprises radially inner and outer cylinders extending between closure members to define a reservoir space between the cylinders which is partitioned by a cylindrical elastomeric membrane into an hydraulic reservoir space and a gas space.A piston connected by a piston rod to a wheel slides in the inner cylinder to define a pump chamber and a first working chamber within the inner cylinder. Each chamber communicates with the hydraulic reservoir space by means of a respective solenoid-operated valve. A pump outlet valve incorporated into the piston controls flow of hydraulic fluid between the chambers. The first working chamber is in communication with a second working chamber by means of flap valves, the second working chamber being separated from a gas spring chamber by a diaphragm.An electronic control unit operates the solenoid-operated valves to adjust the height of the strut, which is detected by a sensor.