Caterpillar 1U1779 Hydraulic Gear Pump Assembly

The 1U1779 is a fixed displacement hydraulic gear pump designed for steering and pilot circuits in Caterpillar medium wheel loaders. It converts mechanical input into hydraulic flow through meshing gear elements, supplying pressurized fluid to cylinders, motors, and control valves. Constructed with cast iron housing and hardened steel gears for wear resistance in contaminated environments. Features flange mounting with splined shaft interface. Rotation direction is clockwise viewed from shaft end. Port configuration follows SAE flange standards for high-pressure and suction connections. Seal package compatible with mineral-based hydraulic fluids. Direct replacement for Caterpillar OEM part numbers 1U1779, 1U-1779, 9V0720, and 9J5763. Interchanges with aftermarket reference CA1U1779. Serial number verified fitment for 980C (63X, 13B, 2XD series), 980F (4RN, 5XJ series), 980F II, 980S, and R1700 II load haul dump machines powered by 3406, 3406B, and 3406C DI engines.