Quick check guide to differences between the CJ-2A and the CJ-3A
Near the beginning of the 1949 model year the new CJ-3A replaced the existing CJ-2A. Willys was constantly making changes and improvements to current production vehicles, thus many characteristics of these 2 models overlap. The closer one gets to the model change point, the less differences there actually are. Since all CJ-2As are not the same and all CJ-3As are not the same, the changes shown below are only the most distinct differences between the two models.
The windshield frame is a significant visual difference between the CJ-2A and the CJ-3A. One of the advertised advantages of the CJ-3A was a taller windshield that gives more headroom. From a distance it is easy to see the upper corners of a 2A windshield frame are square and a 3A has rounded corners. The CJ-2A windshield glass is two piece with square corners while the 3A has a single piece of glass with rounded corners. There is a hinged vent opening in the center of the CJ-3A windshield frame, just below the glass, while on the 2A the entire glass section tilts forward and out. Because these windshield frames are interchangeable it is not always a foolproof method to determine the vehicle type.
Ignition switch location
CJ-2A ignition switches are located toward the passenger side of the dashboard (CJ-2A item #17). On a CJ-3A the ignition switch is just above and slightly left of the gauges (CJ-3A item #11, hidden by steering wheel)
Front seats and rear wheel housing
Willys shortened the top of the rear wheel housing on the CJ-3A to allow for front seats that provided more occupant leg room. At a glance the difference can easily be measured, as shown in the illustration below. A CJ-2A has a 34" wheel housing top and a CJ-3A has a 32" long housing. This is probably one of the best methods to differentiate between a 2A and a 3A body tub.
X is the rear wheel housing length
The seat frame difference is demonstrated in the next photo.
Left front drivers seat frame leg
Tool box lid and gutter
The under seat tool box has a few differences. On a CJ-3A the opening has a "gutter" around the circumference to collect water so it doesn't drip into the compartment. The arrow in the CJ-3A photo is pointing to the gutter drain hole. Below the hole is a trough that carries the water out into the wheel well. The lid outer edge, center reinforcement and latch mechanisms are also different.
Photo by Dan Keister
Top bow storage brackets
CJ-2As came from the factory with top bow storage brackets welded to the side ot the body. Most storage brackets are located on the drivers side but a few 1948 models had the brackets on the passenger side. CJ-3As did not have top bow storage brackets.
Drivers side top bow storage brackets circled
Fuel pump, motor mount and vehicle frame
With the introduction of the CJ-3A came an improvement to the windshield wiper system. A vacuum booster section was added to the bottom of the fuel pump providing better wiper operation under heavy engine loads. Previously the wipers would slow to a stop while accelerating and climbing hills. A different engine front plate was used to allow more space for the larger fuel/vacuum pump assembly. On the CJ-2A both motor mount ears face to the rear. The new CJ-3A plate had the drivers side motor mount ear facing toward the front.
CJ-3A fuel pump (item 22), engine front plate and drivers side motor mount (item 23)
This new arrangement required the driver's side engine motor mount bracket to be located several inches forward on the vehicle frame. CJ-2A motor mount brackets are equidistant from the front of the frame while CJ-3A motor mounts are offset as seen in the photo below.