With the opening of the Meishin Expressway between Nagoya and Kobe in 1965 and the Tomei Expressway between Tokyo and Nagoya in 1968, JNR faced increasing competition for freight transport from road hauliers.
JNR therefore developed the "10000 series" freight wagons (KoKi 10000 and KoKiFu 10000 container flat wagons, ReSa 10000 and ReMuFu 10000 refrigerated wagons, and WaKi 10000 bogie vans) capable of operating at 100 km/h (60 mph).
Express freight services formed of these wagons were introduced on the Tokaido Main Line and Sanyo Main Line from October 1966 using Class EF65-500 electric locomotives built in 1965.
These locomotives were designed to be used in pairs hauling 1,000-tonne freight trains, but as pairs of locomotives drew excessive current from the overhead wires, 1,000-tonne freight trains had to be split into 600-tonne and 400-tonne sections when operating on the Sanyo Main Line.
This led to the need for a new locomotive design that would be capable of hauling 1,000-tonne trains singly.
With the opening of the Meishin Expressway between Nagoya and Kobe in 1965 and the Tomei Expressway between Tokyo and Nagoya in 1968, JNR faced increasing competition for freight transport from road hauliers. JNR therefore developed the "10000 series" freight wagons (KoKi 10000 and KoKiFu 10000 container flat wagons, ReSa 10000 and ReMuFu 10000 refrigerated wagons, and WaKi 10000 bogie vans) capable of operating at 100 km/h (60 mph). Express freight services formed of these wagons were introduced on the Tokaido Main Line and Sanyo Main Line from October 1966 using Class EF65-500 electric locomotives built in 1965. These locomotives were designed to be used in pairs hauling 1,000-tonne freight trains, but as pairs of locomotives drew excessive current from the overhead wires, 1,000-tonne freight trains had to be split into 600-tonne and 400-tonne sections when operating on the Sanyo Main Line. This led to the need for a new locomotive design that would be capable of hauling 1,000-tonne trains singly.
JNR Class EF66