This manual covers the Case 788 and 988 Hydraulic Excavator models. These machines are engineered for robust performance and reliability in demanding operational environments. While specific production years are not detailed, the manual provides comprehensive information intended to support the longevity and efficiency of these excavators. This official factory service and repair manual is designed to be an indispensable resource for owners, mechanics, and technicians. It details general maintenance procedures, troubleshooting guides, and in-depth repair instructions for critical systems including the engine, transmission, brake system, electrical components, cooling system, fuel system, suspension, and steering. Additionally, it includes information on chassis and body, HVAC, emission systems, and operation in various work sites, along with wiring diagrams and recommended lubricants.