This Shop Service Manual provides comprehensive information for the Komatsu 6D105 diesel engine. Engineered for reliability and performance, the 6D105 is a robust internal combustion engine designed for a variety of heavy-duty applications. Its advanced diesel technology ensures efficient power delivery and durability, making it a trusted component in numerous industrial machines. This manual covers various engine model variations, including the 6D105-1A, 6D105-1C, 6D105-1D, and S6D105 series, along with specific engine number ranges. The purpose of this English-language manual is to serve as an authoritative guide for the repair and maintenance of the Komatsu 6D105 engine. It details essential procedures for general information, engine mechanical systems, fuel, exhaust, cooling, lubrication, electrical, intake, and preheating systems. This resource is invaluable for owners, mechanics, and technicians seeking to ensure optimal performance and longevity of their equipment, offering clear instructions and technical specifications necessary for effective service and troubleshooting.