What are the numbers on the ID Plate. That will tell the story. Bertha looks more like a, 1 1/4, 1 1/2, or 2 ton truck to me. What's the ID tag on Bertha say. A 3 ton '42-'55 model GMC will be a 450 series. I noticed you have Bertha listed as a EC 283, which is a 280 series, 1 1/4 ton truck. All of the above, stands true, if these trucks are U.S. built.