The Hitachi ZAXIS ZX30U-3 is a generation 3 crawler excavator engineered for robust performance and reliability in various construction and excavation applications. This model features a powerful diesel engine, a hydrostatic transmission for smooth operation, and a compact design with a width over tracks of 1,550 mm, making it suitable for maneuverability in confined spaces. Its operating weight of 3,050 kg and ground pressure of 0.29 kg/cm² ensure stability and efficiency across different terrains. The ZAXIS ZX30U-3 is built with precision engineering to deliver consistent power and durability, making it a dependable choice for demanding job sites. This Service Repair Manual provides comprehensive guidance for the Hitachi ZAXIS ZX30U-3 crawler excavator. It covers essential maintenance procedures, including fluid capacities and recommended service intervals for engine oil, hydraulic filters, and air filters, along with detailed technical specifications for the engine and machine dimensions. The manual is designed to assist owners, mechanics, and technicians in performing routine maintenance, troubleshooting common issues, and ensuring the optimal performance and longevity of the equipment. All information is presented in English to facilitate understanding and application by a wide range of users.