Abstract: A mobile apparatus supported on a trailer measures, analyzes, and monitors drilling fluids on an oil & gas site. The system includes a modular automated test unit having instruments for measuring and analyzing physical and chemical drilling fluid parameters including but not limited to viscosity, density, pH, electrical stability, fluid loss, rheological parameters, retort analysis, titrations for mF, pF, POM, chlorides, hardness, calcium, and chromatographic analysis. The system further includes a manifold system situated between a drilling mud reservoir and a network of conduits, for distributing drilling fluid to be analyzed by the instruments. Also included is a system hub, coupled as an interface between a program-operated data processing and communication system and the manifold and system instruments, for communicating control and data information and routing storage in a database of the data outputs of the instruments.