This manual covers Oliver Super 55HC, 55, and 550 HC models, primarily produced in the 1950s and early 1960s. These tractors, manufactured by the Oliver Farm Equipment Company in Charles City, Iowa, are recognized for their robust construction and reliability. Designed for utility tasks, these models typically feature gasoline or diesel engines with horsepower in the 40-55 PTO range, a 5-speed or 6-speed transmission, and the Oliver Hydra-lectric system for hydraulic implement control. The Oliver brand is historically significant for its durable and distinctive agricultural machinery, with these utility tractors representing a key part of their popular product line. This Factory Service Repair Workshop Manual provides comprehensive coverage for full service, repair, and troubleshooting of Oliver Super 55HC, 55, and 550 HC tractors. It includes detailed instructions and diagrams for the engine, transmission, chassis, electrical system, and hydraulic system. The manual offers step-by-step repair procedures, diagnostic guides, and maintenance schedules, including fluid specifications and lubrication points. Its professional-level detail, complete with exploded diagrams and photographs, is intended to assist owners, independent mechanics, and restoration specialists in maintaining and repairing these classic Oliver tractors effectively.