Currently, the industry standard pump test which is used to evaluate the lubricating performance of hydraulic fluids is ASTM D-2882 [1,2]. This test, and others, utilizes the Vickers V-104 vane pump . Although ASTM D-2882 has been an industry standard for many years, it does not provide the necessary correlation required for prediction of the lubricating properties of a hydraulic fluid in various piston pump operations. The objective of this paper is to detail the recently proposed Rexroth Piston Pump Test which is being proposed as an ASTM standard. A description of the proposed hardware, pump testing strategies and methods of standardized wear determination will be provided.