 A hydraulic circuit includes a sensor subsystem for sensing the magnitude of the load on the piston-cylinder assemblies and/or members.A fluid supply system includes an actuatable control valve operable to supply fluid to one or both piston-cylinder assemblies.A control circuit is responsive to the sensor and is configured to electronically control the fluid subsystem to supply fluid to the first piston-cylinder assembly when the sensor subsystem senses a load below a predetermined magnitude and to supply fluid to both piston-cylinder assemblies when the sensor subsystem senses a load above the predetermined magnitude.