Chevrolet entered the truck market for the first time in 1918 with the Model T, not to be confused with the Ford car. It was a serious hauler, a one-ton truck with a 125 inch wheel base and solid rubber rear tires. It wasn’t much of a speed machine with an engine governed to a maximum of 25 mph. Given the roads in many areas, that was probably adequate.
Bodies were supplied to Chevrolet in this era, with assembly of the bodies either at the factory or at the dealer’s shop. Martin- Parry was probably one of the first suppliers. Other companies involved with Chevrolet in the early days were Hercules, Springfield, Mifflinburg and Proctor-Keefe. Chevrolet also offered what they called a Light Delivery on their 490 car chassis.
Today, Chevrolet offers a wide variety of commercial trucks. Besides several sizes of pickups, they also offer chassis cabs, cab forwards and cargo vans.
Check out Chevy's Truck Centennial website for lots of photos and stories: http://media.chevrolet.com/media/us/en/chevrolet/centennial.html