Randy in ca
Well-known member
In one of Steve Plucker's articles, much the same was stated as far as the period of only a single "A", but as Stickshift said it doesn't do much to explain the number on John's early 1930 though:
"Starting with engine number A26268, a February 16, 1928 engine, the “AA” prefix was dropped due to the fact that all truck clutch springs were the same weight as the car and commercial vehicles. On May 15, 1928, the Indianapolis Ford Service Letter indicated that all the truck engines were now being equipped with a 455 pound spring and that the engine numbers on such motors were being prefixed with the letters “AA” again".
"Starting with engine number A26268, a February 16, 1928 engine, the “AA” prefix was dropped due to the fact that all truck clutch springs were the same weight as the car and commercial vehicles. On May 15, 1928, the Indianapolis Ford Service Letter indicated that all the truck engines were now being equipped with a 455 pound spring and that the engine numbers on such motors were being prefixed with the letters “AA” again".