This comprehensive Komatsu GD660 and GD670 Series Grader Workshop Service Repair Manual provides detailed technical information and instructions for servicing and repairing these models. The manual covers a wide range of topics, including: * **General Information:** This section contains essential information on safety procedures, specifications, and identification of the GD660 and GD670 Series graders. * **Engine:** Detailed instructions for servicing and repairing the engine, including the cooling system, fuel system, lubrication system, and exhaust system. * **Transmission:** In-depth coverage of the transmission, including troubleshooting, adjustments, and repair procedures. * **Hydraulic System:** Comprehensive information on the hydraulic system, including the hydraulic pump, control valves, and actuators. * **Steering System:** Detailed instructions for servicing and repairing the steering system, including the steering wheel, steering column, and steering gear. * **Brakes:** Thorough coverage of the brake system, including the brake pedal, master cylinder, calipers, and drums. * **Electrical System:** Detailed instructions on the electrical system, including the wiring diagrams, sensors, and actuators. * **Body and Frame:** Information on servicing and repairing the body and frame, including the cab, chassis, and attachments. * **Maintenance and Troubleshooting:** This section provides valuable information on routine maintenance procedures and troubleshooting tips for common problems. * **Parts Catalog:** The manual includes a comprehensive parts catalog, allowing you to easily identify and order replacement parts. The manual covers serial numbers: GD621A-1 (10001 and up), GD622A-1 (20001 and up), GD623A-1 (30001 and up), GD625A-1 (50001 and up), GD672A-1, and more. With its clear and concise instructions, diagrams, and illustrations, this manual is an invaluable resource for technicians, mechanics, and owners of Komatsu GD660 and GD670 Series Graders.

The Komatsu GD660 and GD670 Series Graders are heavy-duty construction equipment designed for a wide range of applications, from road building and maintenance to site preparation and heavy-duty grading. These machines are renowned for their robust construction, powerful performance, and advanced operator comfort features. The GD660 and GD670 are equipped with powerful Komatsu engines, providing ample torque for efficient grading and material handling. The engines are designed for fuel efficiency and low emissions, meeting stringent environmental standards. The machines feature a durable undercarriage with heavy-duty axles and tracks, capable of handling demanding terrain and heavy loads. The GD660 and GD670 Series Graders are designed with operator comfort and safety in mind. The spacious cab provides excellent visibility and a comfortable working environment with ergonomic controls and a suspension seat. The operator cab features a comprehensive instrument panel and intuitive controls for easy operation and precise grading. The GD660 and GD670 Series Graders are also equipped with advanced safety features such as a ROPS (Rollover Protection Structure) and FOPS (Falling Object Protective Structure), ensuring the operator's well-being in the event of an accident. The machines are designed for ease of maintenance with accessible service points and a robust design that minimizes downtime.