This manual pertains to the Komatsu WA900-3 Series wheel loader, a robust piece of equipment designed for demanding operational environments. While specific production years are not detailed, this document covers serial numbers 50009 and up. The WA900-3 is engineered for reliability and efficient performance, featuring advanced systems to enhance operator control and productivity. Its design prioritizes durability and ease of maintenance, making it a valuable asset for heavy-duty applications. This Operation & Maintenance Manual provides comprehensive guidance for the proper use, handling, lubrication, and servicing of the Komatsu WA900-3. It details essential procedures for checking, adjustment, and troubleshooting, along with technical specifications and safety precautions. The manual is structured to assist owners, mechanics, and technicians in maintaining the vehicle's optimal performance and longevity, covering topics from general operation and safety to specific system handling and maintenance schedules.