h was one of the most common tractors made in the US, so unless it is something special, such as very low serial, etc. they are not that great an investment. If one is a dual fuel with everything still there,, original manifold, shutters, etc. that would be a slightly more valuable one, but other than that, the one that appears to have the least wear would be preferable. If everything else is the same, the prewar would be a little more collectible, abut again, only slightly. According to serial numbers there were 41,734 made in 1940, and 14,639 in 1952.