Jeffery Quad

Jefferey Quad
U.S. Marines riding in a Jefferey Quad, Fort Santo Domingo, c. 1916
Overview
Manufacturer	Thomas B. Jeffery Company Nash Motors after 1916
Production	41,674 (1913–1928)
Layout	Front-engine, four-wheel-drive
Powertrain
Engine	Buda, 4.87 litre, 4-cylinder, side-valve motor, 312 cubic inches, developing 28.9 horsepower
Transmission	four-speed, four wheel drive, hub-reduction gearing
Dimensions
Curb weight	7,900 pounds, Payload= 4,000 pounds

The Jeffery Quad, also known as the Nash Quad or Quad is a four-wheel drive truck that was developed and built by the Thomas B. Jeffery Company from 1913 in Kenosha, Wisconsin and after 1916 by Nash Motors, which acquired the Jeffery Company. Production of the Quad continued unchanged through 1928.

The Quad introduced numerous engineering innovations. Its design and durability proved effective in traversing the muddy, rough, and unpaved roads of the times. The Quad also became one of the most successful vehicles in World War I. The Quad was produced in large numbers by Jeffery and Nash, as well as under license by other truck makers.

In the years immediately preceding World War I, Jeffery designed a four-wheel-drive truck, known as the "Quad" or "Jeffery Quad", which greatly assisted the subsequent war efforts of several Allied nations, particularly the French. The Jeffery Quad became the workhorse of the Allied Expeditionary Force.

These unique vehicles also saw heavy service under General John J. "Blackjack" Pershing as both the Jeffery armored car and as regular transports during the Army's 1916 Punitive Expedition through Mexico; Quads were also used extensively during Pershing's later European campaigns of World War I. The United States Marine Corps also adopted the Jeffery Quad, using it in the Haiti and Dominican Republic conflicts from 1915 through 1917.

Approximately 11,500 Jeffery and Nash Quads were built between 1913 and 1919. "Four-wheel drive trucks had been built before ... but aside from the Jeffery Quad (Nash Quad, per subsequent purchase) earlier designs were inefficient, crude, and flimsy."

The Quad had four-wheel drive and four-wheel brakes, as well as an innovative four-wheel steering system. This novel approach to steering allowed the rear wheels to track the front wheels around turns, such that the rear wheels didn't have to dig new "ruts" on muddy curves (most roads of the day were unpaved and often badly rutted).