55-Ton Aluminum Ram Get the strength of a steel ram but about half the weight. Easily carry this single-acting, spring-return ram around the garage, shop, or into the field for on-the-vehicle repairs. It's ideal for truck axle correction, trailer frame straightening, general vehicle maintenance, and heavy-duty lifting. OTC No. 4111 Capacity in Tons: 55 Stroke: 6-1/8" Oil Capacity (cu. in.): 67.6 Effective Ram Area (sq. in.): 11.04 Tons at 10,000 PSI: 55.2 Spring Return: Yes Height Collapsed: 10-3/4" Height Extended: 16-7/8" Piston Protrusion at Collapsed Height: 1/4" Diameter: 5-1/4" Diameter: 3-1/8" Piston Thread (N.P.T.): None Collar Thread (Straight): None Internal Base Thread (N.P.S.M.): None Weight (lbs./oz.): 25/10 Includes No. 9796 3/8" NPTF half coupler; oil port threads are 3/8" NPTF.