Ford Model AA is a truck from Ford. As the Model T and TT became obsolete and needed to be replaced, Henry Ford began initial designs on the Model A and Model AA in 1926. Basic chassis layout was done rapidly and mechanical development was moved forward quickly. Body design and style was developed and then outsourced to various body manufacturers, including Briggs and Murray. The designs of the Model A shared parts and materials with the Model AA Ford, notably the body, engine and interior. The AA usually received plainer interiors than their car counterparts. The Model AA followed similar design changes to the Model A during the AA's four years in production, often delayed anywhere from three to nine months. The mechanical changes and upgrades were done during production of the vehicles. Body changes that occurred between 1929 and 1930 were also integrated into AA production, but leftover parts were used longer in the heavy commercial trucks.