The company was founded by Charles T. Jeffery and Thomas B. Jeffery, and sold under the brand name Rambler between 1902 and 1913. On the death of the founder, Thomas Jeffery in 1910, his son Charles took over the business. In 1915, Charles T. Jeffery, changed the automotive branding from Rambler to Jeffery to honor the founder, his father, Thomas B. Jeffery. Production continued until 1917 when it was sold to Charles W. Nash, former president of General Motors, and formed the foundation of the Nash Motors Company. Nash Motors went on to become Nash-Kelvinator Corporation, in 1954 merging as American Motors Corporation (AMC), finally bought out by Chrysler in 1987 and becoming the Jeep-Eagle Division of Chrysler.
The first Jeffery Rambler was built in 1898 but does not appear to have been sold.
The 1904 Model L Rambler was a larger touring car model. Equipped with a tonneau, it could seat five passengers and sold for US$1,350. The flat-mounted water-cooled straight-twin engine, situated amidships of the car, produced 14 hp (10.4 kW). A two-speed transmission was fitted. The angle steel-framed car weighed 1,900 lb (860 kg).
The 1904 Model K Rambler was a smaller touring car model. Equipped with a tonneau, it could seat four passengers and sold for $1,200, or $100 less without the tonneau. It used the same mid-mounted engine as the Model L, with this model weighing 1,500 lb (680 kg).
- Turning Points In Wisconsin History — "The Jeffery Four." (Kenosha, Wis.: Thomas B. Jeffery Co. 191?), a 28-page pamphlet describing the circa 1916 Jeffrey automobile, retrieved October 23, 2007.
- Frank Leslie's Popular Monthly (January, 1904)