The Komatsu WA800-3 Series represents a robust and powerful wheel loader designed for demanding heavy-duty applications. Engineered for exceptional performance and reliability, this machine is built to handle significant workloads with its substantial operating weight of 47,180 kg and a generous bucket capacity of 6.0 m³. Powered by a Komatsu SAA12V140E-3 diesel engine, it delivers impressive gross power of 397 kW, ensuring efficient operation even under challenging conditions. Its substantial dimensions, including a length of 10,900 mm and a width over tires of 3,450 mm, contribute to its stability and operational effectiveness in various industrial and construction environments. This comprehensive manual provides essential information for the operation and maintenance of the Komatsu WA800-3 Series. It covers critical aspects including detailed maintenance procedures, troubleshooting guidance, and technical specifications for the engine, transmission, and hydraulic systems. Owners, operators, and service technicians will find valuable insights into lubrication requirements, service intervals, and performance capabilities, such as dump clearance and lift capacity. The manual is presented in English and serves as an indispensable resource for ensuring the longevity, efficiency, and safe operation of the WA800-3 wheel loader.