The first design for a close support howitzer on an M5 tank chassis was the T41, which had the howitzer in the hull front. This did not progress past the mock-up stage as the crew would not have been sufficiently protected and design work started on the T47. It was developed on the chassis of the then-new Light Tank M5 (Stuart VI). The prototype was designated the 75 mm Howitzer Motor Carriage T17E1 It had the standard M5 turret removed and replaced with a larger open-topped turret.