Interstate Engine & Tractor Co.

Interstate offered 10-20 Plow Boy as well as a 15-30 model known as the Plow Man. It was nearly identical to the 10-20 but used a Buda engine as opposed to the Waukesha.

Manufacture Logo


Interstate Engine & Tractor Company came about as a reorganization of Sandy McManus, Incorporated in Waterloo in October 1915. McManus had been building “Sandow” gasoline engines but his Board of Directors preferred a more conservative approach than McManus exercised. Interstate was again reorganized about 1919 as Plow Man Tractor Company, but the firm never recovered from its financial troubles and folded shortly after. Throughout its life, the company appeared to be somewhat affiliated with Grand Forks Tractor Company in Grand Forks, N. D. Grand Forks acted as a distributor for the Plow Man line, and may even have marketed some of these units under the “Grand Forks” name.


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# Produced

15-30 Plow Man


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