MF135 PTO shaft size

Sam in TN · Sep 28, 2021

I bent the PTO shaft while bush hogging this spring at a remote piece of property. My dumb a** forgot to bring the shaft home with me so I could order a new one.

Is there a standard size for these? Would like to have the new replacement in hand when I return in a couple weeks. Its 8 hour drive or would just go look myself.

All I know is tractor is a MF135 diesel, and bush hog is an old 6' model that uses a shear pin.

Any help would be greatly appreciated.

Roadworthy · Sep 28, 2021

You may be disappointed with my answer. Generally you buy a "standard size" PTO shaft then cut it to fit. The tractor end is pretty common to all tractors. The mower end may vary with a new end put on the brush hog end to mate with your brush hog. That end does vary.

CobyRupert · Sep 28, 2021

Roadworthy is right, with new PTO shaft in hand, bring a measuring tape and a hacksaw to cut to correct length. That is, make sure it can telescope short enough that it doesn’t “bottom out” in all positions of the mower going up and down on the 3 point hitch and going through ditches and destroy the rear end of the tractor.
….but shafts also come in different horsepower ratings.
Here’s a guide: PTO Basics | Agri Supply Blog | Agri Supply

Dmacleo · Sep 28, 2021

if using a quick hitch like pats keep in mind your shaft will be approx 3" longer that a shaft from a non quick hitch setup. which is why when using implements from friends best to know if they use quick hitch or not.
what I did when cutting new one for tiller was put gc2400 (small enough I can do this) on wheel ramps with tiller on.
I raised/lowered tiller bring tiller input direct in line with pto shaft (tractor sits low enough on ground that tiller down shaft of tiller still higher than pto out) then trimmed so I had 1/4 inch between end of output shaft and pto shaft itself. that way in emergency no matter tiller position in relation to tractor I had room to remove shaft and tiller no matter where sits.
I then made sure at both lowest and highest position (this is where over trim would hurt you) shaft halves themselves were still engaged well with each other.