Looking to buy / rent a box blade in Ohio for a grading project I have going on. Would be used on a Mahindra Max so something on the smaller side, like a 4', 5', or 6'.
The big one is, what tires do you have? Ag's/R1 can pull more, R4's/Industrial tires tend to slip.
Are they loaded with extra ballast?
"grading project" Is vague, are you moving a mountain or skimming off a few inches.
What is the soil type... rocks? Large or small?
I have 28hp and use a 6 footer, I can easily turn it from a box blade into an anchor... It's on the large size for me but I can use it with some common sense. You have 22hp, IMO, 4 foot might be too small (depends on the above) and 6 foot might be a bit too large - I'll leave the choice to you