Air / Hydraulic Pump With shop air as the energy source, this pump has the power and oil capacity (80 cu. in. usable oil) to drive even the large 55-ton rams. It's an ideal all-around power source for dozens of body, frame, and alignment applications. It can be used with a variety of rams, presses, and hydraulic pullers operating at up to 10,000 PSI. An internal relief valve protects the hydraulic components regardless of hydraulic pressure. In addition, a two-stage release mechanism gives fast or metered ram return while reducing hydraulic shock. The 4022 is equipped with a 2-gal. reservoir. This pump requires 9 cfm at 100 PSI air pressure at the pump. No. 4022 � Air/ hydraulic pump with a 2-gallon (442 cu. in.) plastic reservoir. Performance @ 100 PSI Hydraulic Pressure* Oil Delivery 0 PSI..............................59 cu. in./min. 5,000 PSI.......................30 cu. in./min. 10,000 PSI.......................4 cu. in./min. * Oil delivery based on 20 cfm air supply at the pump.