Big Four tractors were produced by the Gas Traction Co. of Minneapolis, Minnesota. This company had started out in 1906 as the Transit Thresher Co., but in 1908 it changed its name to reflect its growing interest in tractor production. A number of different four-cylinder models were produced, but the most successful of these was the Big Four "30", a huge 30-60hp tractor with rear wheels eight feet in diameter and two feet wide. A second factory was opened in 1910 at Winnipeg, Canada to satisfy Canadian demands for big powerful tractors - this coincided with numerous successes in the Winnipeg Trials held nearby. In 1912 the Gas Traction Co. was taken over by Emerson-Brantingham, who continued to market the Big Four range of tractors for several more years.

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