This manual pertains to Mitsubishi vehicles equipped with the 4D6 engine family, a series of inline 4-cylinder diesel engines. These engines, commonly found in various Mitsubishi models, feature indirect injection and water cooling. While specific model years are not detailed, the 4D6 engine typically displaces 1.7 liters and offers a power output ranging from 55 to 75 horsepower, depending on the specific application and turbocharging. The engine family is known for its robust engineering, aiming for reliability in diverse operational environments. Transmission options generally include manual (often 5-speed) and automatic configurations, tailored to the specific vehicle. This Service Repair Workshop Manual provides comprehensive instructions for mechanics to maintain and repair vehicles featuring the Mitsubishi 4D6 diesel engine. It covers essential maintenance procedures, including engine oil and coolant capacities, filter types, and timing belt replacement intervals, along with details on the glow plug system. Troubleshooting guidance addresses common issues such as glow plug failure, injection pump problems, and turbocharger concerns. Detailed service procedures are included for engine overhaul, fuel pump and radiator removal/installation, ensuring thorough support for all aspects of engine and related system maintenance.