This manual pertains to the Hino RB145 W04D Engine, designed for robust performance and reliability. It is intended for mechanical technicians already familiar with general automotive service procedures. The engineering quality and reliability of the Hino RB145 W04D Engine are paramount, and this manual provides the specific details necessary to maintain that standard. It emphasizes the unique aspects of this engine's components and their functions, enabling technicians to deliver quality service and ensure optimal performance. The purpose of this comprehensive service manual is to guide owners, mechanics, and technicians through the maintenance, diagnosis, and repair of the Hino RB145 W04D Engine. It covers a wide range of topics, including routine maintenance, tune-ups, removal and installation procedures, assemblies and disassemblies, and detailed information on various systems such as fuel, ignition, lubrication, exhaust, and electrical. The manual also addresses more extensive repairs involving engine and transmission disassembly, providing reliable information and procedures to help users achieve the best possible value and longevity from their Hino RB145 W04D Engine. Safety precautions and the use of special tools are also highlighted.