Based on WW2 Canadian Army Chevrolets, the same weight class truck could be fitted with either 4 blade or more fans depending more on where it was expected to be used (Africa, India, UK, arctic?) than the weight class (3/4 ton to 3 ton load). The radiators also didn't change much, if at all for the different weight classes. All very nice - if it looked the same and fit the same it would basically work the same...