a lift gate assembly including a u - shaped base having horizontal central section flanked by parallel upstanding legs , a gate , and a pair of upstanding legs secured to the gate in alignment with the legs and the base . links extending between the legs define two parallelogram linkages and a torsion bar extends between and is rigidly attached to a corresponding link in each of the parallelogram linkages . preferably , the torsion bar defines the lower pivot of the parallelogram linkage and extends between the legs of the base and the lowermost links in each parallelogram linkage , being rigidly attached thereto . hydraulic cylinders are provided for each parallelogram linkage to raise and lower the gate .