This workshop service repair manual covers a range of tractors, including the 480, 480 DT, 500, 500 DT, 540, 540 DT, 580, 580 DT, 640, 640 DT, 680, and 680 DT models. These tractors, known for their robust construction and utility in agricultural applications, are powered by reliable 4-stroke Diesel engines, with displacements ranging from 2592 cc (3-cylinder) for the 480 and 500 series, to 2750 cc (3-cylinder) for the 580 series, and 3456 cc (4-cylinder) for the 640 and 680 series. The brand, Fabbrica Italiana Automobili Torino, has a long-standing reputation for engineering quality, making these tractors a valuable asset for various farming tasks. This comprehensive manual provides detailed, step-by-step instructions, diagrams, and pictures for routine maintenance and major repairs. It covers essential systems including the engine, powertrain, clutch, transmission, brakes, hydraulics, PTO, and electrical systems. Included are procedures for engine repair and overhaul, transmission servicing, brake system maintenance, hydraulic system servicing, and electrical system diagnosis. A dedicated troubleshooting section, along with recommended service tools and wiring diagrams, ensures that both do-it-yourself owners and experienced mechanics can effectively maintain and repair these tractors, keeping them in optimal working condition.