The Komatsu PC800-8 is a robust excavator from the 8 Series, engineered for demanding heavy-duty applications. It features a powerful Komatsu SAA6D140E-5 diesel engine, delivering 380 HP and meeting EPA Tier 3 / EU Stage IIIa emissions standards. This machine is designed for exceptional performance, with a hydrostatic transmission, a substantial operating weight of approximately 79,300 kg, and impressive digging capabilities including a maximum digging depth of 7,575 mm and a bucket capacity of 4.4 m³. Its substantial dimensions and robust construction ensure reliability and efficiency in various construction and earthmoving environments. This Full Service Repair Manual provides comprehensive guidance for the Komatsu PC800-8. It covers essential maintenance procedures, detailed troubleshooting steps, and critical technical specifications necessary for optimal operation and longevity. The manual is designed to assist owners, technicians, and mechanics in performing routine servicing, diagnostic checks, and repairs. Key areas include engine oil, hydraulic oil, coolant, and fuel capacities, along with detailed information on the hydrostatic transmission and performance capabilities, ensuring the machine remains in peak working condition.