This Service Workshop Shop Repair Manual covers Komatsu WA300-1, WA320-1, and WA320 models, generation 1, for serial numbers 10001 and on. These machines are engineered for demanding operational environments, featuring robust construction and reliable performance. The diesel engines with injection fuel systems and hydrostatic power shift transmissions provide efficient power delivery for various tasks. This manual details the engineering quality and unique selling points that make these models a trusted choice for heavy-duty applications. This comprehensive English-language manual is designed to assist owners and technicians in maintaining and repairing their equipment. It includes detailed procedures for engine, transmission, hydraulic system, and chassis component repairs. Furthermore, it offers a comprehensive troubleshooting guide, complete with wiring diagrams and electrical schematics, to quickly diagnose and resolve issues. By following the guidelines within this manual, users can ensure optimal performance, longevity, and safety of their Komatsu equipment.