its not real meaning other than saying thats its a 1/2 ton, just like 1500 is the 1/2 ton with chevy/gmc and dodge, 250 and 350 are the heavier duty trucks that you have an option of getting a diesel in, 250 is the 3/4 ton and 350 is 1 ton, just like 2500 in chevy/gmc and dodge is 3/4 ton and then 3500 is 1 ton