1945 1950 dating
Later in 1949, and for the remainder of production, the body tag was eliminated. The body tag to the left is from a 1949 CJ-3A, thanks to Andy Testo for the photo.Body tag numbers are initially close to the vehicle serial number and then skew to about 1200 less than the vehicle serial number. Early in the 1949 model year Willys began to build their own bodies.Willys Service Bulletin 53-5 explains "the effective serial numbers given apply to changes made in vehicles assembled at the Toledo plant and do not apply to those assembled in our west coast plant".The CJ-3As military sibling, the M38, also went through many changes.The commonly accepted description of the CJ-3A seems to apply only to the mid production vehicles.The lack of factory parts information from the CJ-3A time period makes it very difficult to decide if and when changes were made.The CJ-3A was produced for five model years, 1949 to 1953.Two other civilian Jeep models overlapped the CJ-3A's production.
Many of the listings in the 1945-1949 Parts Master List are for years later than 1949. To further complicate things Willys also had a manufacturing facility in California.Prior to that American Central Manufacturing (ACM) manufactured the bodies.Engine changes The engine serial number is stamped on the boss between the water pump and cylinder head; click on the engine serial number illustration at the right for the location.Starting in 1951, and continuing through final production, a new format was used.The prefix was changed to indicate the model and model year and the serial number itself was reset to 10001 at the beginning of each model year.