After the Dodge Brothers sold their interest in their bicycle company in 1900 (see Early History), they established a machine shop in Detroit at the Boydell Building on Beaubien Street at Lafayette. They began with only twelve employees, but quickly established a reputation for excellent workmanship. Consequently their business grew and forced them to move to larger quarters at Hastings Street and Monroe Avenue. When they left there in 1910 for the spacious Hamtramck site, the Hastings Street plant was the largest and best-equipped machine shop in Detroit. Ransom E. Olds erected the first automobile plant in Detroit in 1899 and by early 1901 the Dodge machine shop supplied him with engines. Olds followed with an order for 3,000 transmissions in 1902, making the Dodge brothers one of the largest parts suppliers for the nascent Detroit automobile industry.
On February 23, 1903 the Dodge brothers formally agreed to supply Henry Ford with 650 chassis (including engines, transmissions, and axles) for $250 each, thus beginning a profitable, but stormy relationship between the two firms. This contract kept the 150 men at the Hastings Street plant fully occupied and the Dodges began working exclusively for Ford. He built a plant on Mack Avenue to assemble cars from parts made elsewhere, the entire operation dependent upon extensive credit from his parts suppliers. In return for an investment of $10,000 ($7,000 in materials and a $3,000 bank note), the Dodge brothers accepted 100 shares (one-tenth of the total) in the Ford Motor Company., newly-incorporated on June 16, 1903. Dodge delivered the first shipment of chassis to Mack Avenue in July via horse-drawn hayracks and the Ford Motor Company assembled its first cars. During these early years. Ford often complained that the Dodge workers turned out shoddy products because they were paid by the piece. Despite these problems, he ordered another 755 engines for delivery in January through May 1904, and insisted on the right to order 500 more by early April. By the spring of 1905, when Ford had moved into his new Piquette Avenue plant. Dodge Brothers supplied 400 "rigs" (engines and transmissions) a month. Dodge continued as the major supplier, but by late 1905 Ford was already taking steps to produce his own engines and transmissions for the low-priced Model N.
The fates of Ford and the Dodges remained intertwined for fifteen years. The Dodge brothers began erecting a new plant on their thirty acre site in Hamtramck in 1910, the same year Ford opened his Highland Park complex. In 1912 they supplied Ford with 180,000 transmission-axle sets, with future prospects for much larger orders. Fearing their total dependence on one customer, particularly because it was Ford, the Dodges gave Ford the required year's notice that they would terminate their contract effective August 1914.