Product Overview This hydraulic main piston pump is the core power component of the excavator hydraulic system, compatible with E320C and E320D models. It supplies pressure oil for boom, arm, bucket, and travel movements. Manufactured with precise processing, it delivers stable output pressure and excellent wear resistance, making it an ideal choice for machine overhaul and replacement. Interchange Part Numbers 173-3381, 272-6955 Compatible Models E320C, E320D, 323D Excavator