According to The Complete Encyclopedia of Commercial Vehicles the Stewart Motor Corporation of Buffalo in New York produced vehicles between 1912 and 1941. Stewart built their own bodies as well having custom bodies and in 1929 introduced the aluminium body, the first ever made by a chassis maker. From 1930 the Stewart range consisted of six models from 1½ to 6-7 tons, powered by Lycoming or Waukesha engines. In 1937 the body was restyled and pontoon fenders resembling those of the Diamond T and tear drop head lamps were introduced. Stewarts best year for sales was 1930 with 2,300 units delivered but numbers declined and in 1938 only 390 units were sold and in 1939 only 90.