The Nuffield Universal 3 and Universal 4 are robust diesel-powered tractors, produced primarily in the 1950s and 1960s. These British-manufactured machines were engineered for reliability and efficiency, serving as workhorses in agriculture and land management. Featuring vertical, water-cooled diesel engines with displacements of approximately 2.5 liters for the 3-cylinder models and 3.3 liters for the 4-cylinder variants, they provided dependable power for a range of tasks. Their design emphasizes mechanical simplicity and durability, making them enduring assets for owners, mechanics, and restoration enthusiasts. This comprehensive service and repair manual provides detailed information for maintaining and troubleshooting your Nuffield Universal tractor. It covers all essential systems, including engine mechanicals, fuel, transmission, clutch, PTO, hydraulics, steering, brakes, front and rear axles, and electrical systems. Within its hundreds of pages, you will find step-by-step repair procedures, overhaul instructions, routine maintenance schedules, troubleshooting guides, and critical technical specifications, all supported by numerous diagrams and photographs. This resource is designed for professional mechanics and experienced DIY users, ensuring you have the factory-level knowledge to keep your tractor in optimal working condition.