The International Harvester 1256 is a heavy-duty agricultural tractor produced approximately between 1967 and 1970. Renowned for its robust construction and powerful performance, this model was a significant advancement in its series, offering a potent diesel engine, a sophisticated 16-speed PowerShift transmission, and an advanced hydraulic system designed for demanding farm tasks. Its legendary DT-466 engine, known for its durability, and the reliable Torque Amplifier (TA) system made it a formidable competitor against other major manufacturers of its time, solidifying its reputation as a dependable workhorse in the agricultural sector. This comprehensive factory service repair manual provides in-depth guidance for the maintenance and repair of the International Harvester 1256 tractor. It covers all major systems, including detailed procedures for the engine, transmission, hydraulics, electrical system, front and rear axles, brakes, operator station, and hitches. The manual includes essential information on scheduled maintenance, fluid specifications, troubleshooting diagnostics, component overhaul, and adjustments, ensuring that owners, mechanics, and technicians have the necessary resources to keep this powerful machine operating efficiently and reliably.