In July 1941, the
US Army Ordnance issued specifications for a medium armored car alongside a specification for heavy armored car (which resulted in the
T18 Boarhound).
Ford Motor Company built a
six wheels, all driven (6 x 6) prototype which was designated T17 and
Chevrolet a
four wheels, all driven (4 x 4) model designated T17E1. At the same time, the
British Purchasing Commission was also looking for medium and heavy armored cars for use in
the war in North Africa. Had the U.S. adopted this, it would have been called the M6.
Both the T17 and T17E used the same turret which was designed by Rock Island Arsenal with British requirements driving some of the design features such as putting at least two crew in the turret and placing the radio in the turret so that it was close to the commander.
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