The Nuffield Universal Three and Universal Four represent a significant lineage of British-manufactured tractors, produced from the 1940s through the 1960s. These robust machines were known for their reliability and utility, serving as essential workhorses in their time. This manual covers the comprehensive range of Nuffield tractors from this era, designed to provide owners and mechanics with the detailed information necessary to keep these dependable vehicles operational. This workshop service repair manual is an exhaustive resource designed to guide users through all aspects of maintenance and repair for the Nuffield Universal Three and Universal Four tractors. It includes detailed procedures for routine maintenance, tune-ups, lubrication, and troubleshooting, alongside complete instructions for disassembly and reassembly of all major systems. With hundreds of illustrations and detailed substeps, this manual is an indispensable tool for DIY enthusiasts and professional mechanics alike, ensuring the longevity and optimal performance of these classic tractors.