The Fiat 55-66 DT LP is a robust utility tractor from the esteemed 66 Series, produced likely in the late 1980s and 1990s. Known for its reliability and value, this Italian-engineered machine is designed for a wide range of agricultural tasks, offering versatility through its implement attachment capabilities. The "DT" designation signifies its four-wheel-drive system, enhancing traction and performance, while the "LP" likely indicates a low-profile configuration. This tractor embodies the engineering quality that made the 66 Series a successful and durable line, making it a dependable choice for farmers and agricultural professionals. This comprehensive factory service repair manual provides complete coverage for the Fiat 55-66 DT LP tractor. It details maintenance procedures, troubleshooting guides, and technical specifications essential for keeping the vehicle in optimal condition. The manual covers all major systems, including the engine, transmission, powertrain, electrical system, hydraulics, cooling, fuel, braking, and steering. It also includes procedures for disassembly, assembly, rebuilds, adjustments, and torque specifications, along with wiring diagrams. This resource is invaluable for owners, mechanics, and technicians seeking to perform routine maintenance, diagnose issues, and conduct repairs effectively.