The Fiat 55-90 is a robust utility tractor, part of Fiat's esteemed 90 series, renowned for its operational reliability and solid construction. Produced likely in the late 1980s and 1990s, this Italian-engineered machine offers approximately 55 horsepower, making it suitable for a range of agricultural and industrial applications. Its design emphasizes durability and performance, featuring a likely 4-cylinder diesel engine, a synchronized manual transmission with PTO options, and an integrated hydraulic lift system. The 55-90 represents a significant offering in its class, designed for demanding work and long service life. This comprehensive workshop service and repair manual provides essential information for maintaining and repairing the Fiat 55-90 tractor. It covers all major systems, including detailed procedures for the engine, fuel, cooling, lubrication, ignition, transmission, drivetrain, braking, steering, electrical, and hydraulic systems. The manual includes step-by-step instructions for maintenance, troubleshooting, repair, overhaul, disassembly, assembly, and adjustments. Designed for professional mechanics and informed owners, this extensive English-language resource ensures that the Fiat 55-90 can be kept in optimal working condition, offering significant savings on service and repairs.