This shop manual provides detailed service and repair instructions for the Komatsu D150A-1 and D155A-1 bulldozers. It includes comprehensive procedures for diagnosing, troubleshooting, and repairing key components such as the engine, transmission, hydraulic system, undercarriage, and electrical system. The manual offers step-by-step guidance on disassembly, inspection, reassembly, and adjustment of parts, along with maintenance schedules and technical specifications. This document is essential for mechanics and technicians to ensure the proper maintenance, efficient repairs, and optimal performance of the D150A-1 and D155A-1 bulldozers.