This Operation & Maintenance Manual provides comprehensive information for the KOMATSU WA120L-3MC Wheel Loader, serial numbers 54104 and up. Engineered for reliability and performance, this machine is designed to meet demanding operational needs. Its robust construction and advanced features ensure efficient and effective work across various applications. Understanding the intricacies of this equipment is key to maximizing its potential and ensuring long-term productivity. This manual serves as an essential resource for owners, operators, and technicians. It details critical procedures for operation, maintenance, and troubleshooting, ensuring the machine performs at its peak. Covered topics include safety precautions, lubrication, checking and adjustment procedures, wear parts, and specific guidance for cold weather operation and long-term storage. With detailed explanations, pictures, and diagrams, this manual is designed to facilitate economical and safe machine operation and maintenance.