This Service Repair Workshop Manual covers the Komatsu WA90-5 and WA100M-5 Series wheel loaders, designed for robust performance in various material handling applications. These machines are engineered for reliability and efficiency, featuring a powerful Komatsu S4D102E-1 diesel engine and a versatile hydrostatic transmission. With substantial operating weights, ample bucket capacities, and a focus on operator comfort and control, the WA90-5 and WA100M-5 are built to meet the demands of construction, agriculture, and industrial environments. Their durable construction and thoughtful design ensure consistent operation and productivity. This comprehensive manual provides essential information for the maintenance and repair of your Komatsu WA90-5 or WA100M-5 wheel loader. It details critical procedures, including safety precautions, general information, structure and function explanations, testing and adjusting guidelines, and disassembly and assembly instructions. Furthermore, it covers fluid capacities, service intervals, and key maintenance points such as greasing and filter locations. This manual is an indispensable resource for owners, mechanics, and technicians seeking to ensure the optimal performance, longevity, and safe operation of these powerful machines.