donn hewes

Hi Chandler, I don't think it is eaxctly a question of which tractors had "ground drive PTO's" they were all made to have engine driven PTO's, but it is a question of where in the drive line the PTO originated. If it came from the engine directly then shifting gears might not work. Some had different clutches for the transmission and the PTO. Some vintage tractors had final drives, or extra gear reductions at the wheels that might have increased torque for pulling power. Unfortunately unless a person is a expert in vintage tractor mechanics you are kind of guessing. On the case tractor we used, the PTO shaft would spin free when disengaged. This meant the clutch was not involved. By jacking it up I could depress the the clutch and by spinning the tire I could spin the PTO shaft. Take it out of PTO and it stopped. Take it out of gear and it stopped. Shifting gears made the PTO spin at different rates even just turning the rear wheel by hand. That was a scientific as I got. I think there was some luck involved in finding the case VAC (late 1940's?) It turned out to be a good size and weight, with good tall but narrow tire. A tall tire works well for ease of pulling. I think other tractors form that era might work equally well, but I wouldn't know which to recommend. I hope this helps, Donn