National Institute for Land and Infrastructure Management (NILIM) has been researching a logistics support service by using ITS-Spot in order to settle safer and eco-friendly logistics management system. NILIM has conducted field operational tests (FOTs) to assess the effectiveness of a newly developed system; named “Support for prevention of overshooting curve” (called “the safe curve system” in this paper) for truck s by introducing this service on the typical accident prone curve; Kumano-chocurve (outbound) on the Ikebukuro Line (No. 5) of the Metropolitan Expressway. Furthermore, NILIM developed a brand new voice-output on board units with Global Positioning System (GPS) module (called “GPS-V-OBU” in this paper). It would be possible with the new GPS-V-OBU to obtain the information about driving routes and required traveling time. New services for drivers and logistics companies would be provided by means of the GPS-V-OBU and thus the performance of it was examined. The results of the examination will be introduced in the paper.