The Nuffield Universal Three and Four series tractors, produced from the mid-1950s to the early 1960s, represent robust and reliable agricultural machinery designed for general farm work. These models, including variants such as the 3DL, 4DM, 424, and 442, were powered by the dependable BMC OEC (Leyland) 3.4L 3-cylinder diesel engine, offering essential power and torque for their intended applications. Known for their simple, durable design and ease of maintenance, Nuffield tractors were built to last and were a common sight in fields across the United Kingdom. Their engineering prioritized functionality and longevity, making them a practical choice for farmers seeking dependable performance.

This factory repair and service manual provides comprehensive guidance for the Nuffield Universal Three and Four tractors. It covers a wide array of systems, including detailed procedures for the engine, cooling system, fuel system, clutch, gearbox, transmission, steering, front axle, wheels, tires, and braking system. The manual also addresses the electrical system and optional equipment, offering step-by-step instructions for disassembly, repair, and reassembly, along with essential maintenance schedules, fluid specifications, and troubleshooting advice. This resource is invaluable for owners, mechanics, and technicians aiming to maintain, repair, and preserve the operational integrity of these classic agricultural machines.