Patent attributes
A pseudo four-leg leveling system for a vehicle, such as a recreational vehicle or the like, includes four jacks in the form of hydraulic cylinders mounted in pairs at the front and rear of the vehicle. A power system supplies hydraulic fluid to extend and retract the jacks thereby adjusting the attitude of the vehicle relative to level. The front two jacks are driven in parallel and the rear jacks are driven separately and independent of the front jacks. When the power system is de-energized the front jacks are hydraulically isolated to improve the stability of the system when static. Pressure operated valves automatically control the isolation of the jacks driven in parallel, as well as return passage to the tank, without the need for additional electronically controlled valves.