The Model AA Ford chassis was significanty different from the standard Model A Ford Chassis. It was designed to serve as a large truck chassis instead of a car chassis. Most of the Model AA bodies were larger and heavily constructed for commercial work. The chassis' were significantly heavier in construction and would tolerate more abuse than a car chassis. Most of the differences between a Model A and Model AA could be found in the chassis and drivetrain. The rear end, brakes, suspensions and transmissions were different than in the Model A. All of these pieces were significantly larger and stronger when compared to Model A p