looks like Minneapolis Moline PTO Output Shaft Part Number: HT158281A

I believe its a countershaft sprocket. The fine splined end fits the sprocket, transmission gears on opposing end. Probably a 3 speed.

References:

Out of memory, or lack of. Harley early factory manuals.

Reason:
Thank you for your opinion, but I was unable to find a countershaft that looks like this. We believe it's a PTO shaft. Do you know what it could go to?

you have it right, its a PTO shaft. goes inside of a gearbox which are connected to a motor to slow down the speed of what is being driven(conveyor lines, fans) the right side sticks out of the gearbox( usually a coupling or a sheave goes in it) and the other side is inside the gearbox, that's why you see the splines on the left side of the shaft(made for a gear) the bearing would sit inside the box as well. if it were sitting inside the gearbox you would only see the snap ring & the right side of the shaft.

References:

http://www.bostongear.com/

Reason:
thank you for the opinion, but I am looking for what make and model this will fit

this is an input shaft for a manual transmission most likely for a diesel

References:

books

Reason:
Could you identify precisely which make, models and years vehicle this fits? Please provide a reference link if at all possible.

looks like Minneapolis Moline PTO Output Shaft Part Number: HT158281A

References:

agkits.com