This manual pertains to the Clark PWD 30-40SE and HWD 30-40SE series, models PWD 567 and HWD 567. These vehicles are engineered for robust performance and reliability, embodying Clark's commitment to quality in industrial equipment. Their design focuses on efficient operation and durability, making them suitable for demanding operational environments. The purpose of this Factory Service/Repair/Workshop Manual (SM-643) is to provide comprehensive guidance for the maintenance and repair of the specified Clark models. It covers essential areas including periodic service, battery service, electric motor and drive unit maintenance, hydraulic system procedures, chassis components, and sheet metal repair. Additionally, the manual includes crucial technical data such as truck specifications and wiring diagrams, empowering owners, mechanics, and technicians to ensure optimal performance and longevity of the equipment.