This workshop service repair manual covers the Komatsu PC300HD-8 and PC300LC-8 excavators, part of the PC300-8 Series. These machines are engineered for demanding construction and earthmoving applications, featuring a robust design and reliable performance. Powered by the Komatsu SAA6D114E-3 engine, a turbocharged, intercooled, direct injection diesel engine, they deliver substantial net power of 204 kW (273.5 HP). The hydrostatic transmission provides variable speed control, while features like the ROPS/FOPS certified cab ensure operator safety and comfort. With impressive digging depth and reach capabilities, these excavators are built for efficiency and durability in various work environments. This comprehensive English-language manual provides essential information for maintaining and repairing your Komatsu PC300HD-8 or PC300LC-8 excavator. It details critical maintenance procedures, including fluid capacities and service intervals for engine oil, hydraulic oil, and air filters. The manual also covers technical specifications, troubleshooting guidance, and performance data related to the hydraulic system and travel speeds. By following the instructions and procedures outlined within, owners, mechanics, and technicians can ensure the optimal performance, longevity, and safe operation of their equipment.