Featured here is a rare 1956 International S-120 3/4 Ton Pickup.

international trucks
1956 International S-120

The light duty S-Series, which came out in for the 1956 model year as light and medium duty trucks, incorporated a style setting design, a new power plant and increased all-round ruggedness and durability. The S-Series for light duty trucks ended just one year later with the 1957 models. The light duty trucks were then replaced by the A models.

The Early Auto Wagon

International Harvester was an early manufacturer of medium and heavy-duty trucks International Harvester entered truck business in 1907 with the high-wheeled, two-chamber “Auto Wagon”. These first Auto Wagons were built by two to three man teams.

International’s  Auto Wagon’s air-cooled engine produced about 15 hp. The vehicle had high ground clearance that made it popular in rural areas with their poor road conditions at that time. Another benefit of the Auto Wagon was that its rear seat converted to a cargo bed. Here you had the beginnings of the pickup truck.

international s-120International Harvester in real terms brought automation to the farming community. The air-cooled engine Auto Wagon was designed to pull farm material and crops over very rugged roads.

There were only 73 Auto Wagons built the first year. However, 725 were produced the next year. A more efficient system of production allowed just under 2,500 Auto Wagons to be built during the third year.  It was this start that officially launched International Harvester into the motor truck business.

The Medium and Heavy Duty Truck Business

International Harvester was right alongside Mack Trucks and White Motor Company in being one of the early companies building medium and heavy duty trucks. International’s truck chassis also became the leader in the chassis for body on school buses.

The final International light line truck was built on May 5, 1975.

1956 International S-120 Specifications

The 1956 International S-120 was built with an International Black Diamond 240 cubic inch valve in head engine. Horsepower was 131. International built Green Diamond engines, Black Diamond, Silver Diamond engines as well as the Red Diamond. All the 1956 models list Red Diamond ‘s or Black Diamond’s.

Brakes were four wheel hydraulic drums.

Dimensions for the S-120 included a 122.0 inch wheelbase, an overall length of 200.6 inches. Nominal gross carrying capacity was 3,500 lbs. Wet weight was 3,908 lbs.

Production of the light duty S series ended in 1957, when it was replaced by the A Series.

Related Auto Museum Online article are found on the links below…

1956 Chevrolet 3100 Half Ton

1957 GMC 100 Half Ton

References for this article includes…International Harvester Trucks: The Complete History by Patrick R. Foster…Lost Truck Legends: An Illustrated History of Unique, Small-Scale Truck Builders by Robert Gabrick.

International Pickup Collector Values

56 international s 120 specsInternational light duty pickup trucks from the 1950’s are a rare thing today and they can be found in a wide range of conditions. Everything from a non running example to a recently restored model.

Because of this, the asking price for any of these you may come across can cover a wide range.

Current asking prices are in a range from a few thousand dollars for a major project example to the $40,000 plus range for a recently frame off expertly restored model from the 1950’s.


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(Article and photos copyright Auto Museum Online)