Allis-Chalmers Model 6-12

The Allis-Chalmers Model 6-12 was a farm tractor produced by Allis-Chalmers between 1918 and 1923. Like many other tractors of the era, its model name came from its horsepower ratings, with 6-12 (or 6/12) meaning 6 hp at the drawbar and 12 hp at the belt pulley.

The Allis 6-12 was an early attempt at a lightweight, versatile, low-cost, general-purpose tractor that would be suitable for all of the work on a farm, including not only traction work (such as ploughing and harrowing) and belt work (such as threshing and sawing) but also cultivating. Like other two-wheel tractors, it used its implement to provide the rear axle to make up a four-wheel articulated unit, with the operator riding the implement.

The Allis 6-12 entered the market at a time when the mechanization of agriculture was underway but was far from complete. Tractors had not yet managed to completely replace the horse team for all farm tasks. The product category of row-crop tractors as we know them today had not yet been developed, and the Allis 6-12 had a very attractive value proposition. Unfortunately that proposition was also suspiciously similar to that of the Moline Universal tractor, which had been on the market for about 2 years before the Allis 6-12 appeared. Moline Plow considered the Allis 6-12 a patent-infringing copy. The late 1910s were a period when various two-wheeled and three-wheeled tractors were on the U.S. market. Moline Plow had by no means invented such configurations. However, the Allis 6-12 was especially similar to the Moline Universal, lending credibility to Moline Plow's assertion that it was a copy.

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