The Komatsu PC128UU-2 is a robust piece of construction equipment designed for demanding work environments. Featuring a powerful Komatsu S4D102E-1 diesel engine with a displacement of 3.9 L and an output of approximately 90 HP, this machine is built for efficiency and reliability. Its hydrostatic transmission and 4WD system provide excellent maneuverability and power distribution, making it suitable for a wide range of excavation and material handling tasks. With an operating weight of 12940 kg and a track shoe width of 600 mm, the PC128UU-2 offers stability and low ground pressure for operation on various terrains. This Workshop Service Repair Manual provides comprehensive guidance for the Komatsu PC128UU-2. It covers essential maintenance procedures, including engine oil and hydraulic filter replacement schedules, along with detailed fluid capacity information for the engine, hydraulic tank, and coolant. The manual also includes technical specifications for the hydraulic system's performance, undercarriage details, and physical dimensions. This resource is intended to assist owners, mechanics, and technicians in performing routine maintenance, troubleshooting issues, and ensuring the optimal performance and longevity of the PC128UU-2.