The Fiat Trattori 640 and 640DT represent a lineage of robust agricultural tractors, produced primarily in the late 1970s and 1980s. These diesel-powered machines, typically offering around 60-70 horsepower, were engineered for demanding farm work, embodying Fiat Trattori's reputation for durability and reliability. The 'DT' designation often signifies dual-traction or four-wheel drive capability, enhancing their versatility in various field conditions. These tractors are characterized by their functional design, focusing on practical performance and ease of operation for agricultural professionals. This comprehensive service repair manual provides detailed information essential for the maintenance and repair of the Fiat Trattori 640 / 640DT. It covers a wide array of systems, including engine overhaul, transmission service, hydraulic systems, electrical diagnostics, braking, cooling, fuel, and steering. The manual offers step-by-step repair procedures, disassembly and assembly instructions, maintenance routines, and troubleshooting guides, making it an invaluable resource for professional technicians and DIY mechanics with basic mechanical and electrical knowledge. Its content is comparable to factory service manuals, ensuring thorough guidance for keeping these tractors in optimal working condition.