Difference between MD O-4 and OS-4

[Gilles Cote]

What is the difference between O-4 and OS-4 tractors? Could it be the 5th gear on an OS-4 which requires you to be going downhill with a tailwind before shifting into 5th?

 

[Anonymous-0]

The OS4 is an Orchard model of the Super W4, The O4 is an earlier model comparable to the W4. Never had any problem hauling a loaded wagon in 5th with our W4 and it was one of the first made cut down off steel.
Later Bob

 

[tobaccoman]

The main difference between the two is that the O-4 has the full coverage rear fenders and the extra front sloping sheet metal, also known as "batwings". Also, the O-4 usually has the cowling covering the operator. The OS-4 has rear fenders similar to the W-4 and no additional front sheet metal. Hope this info is helpful.
Tobaccoman

 

[John M]

OS4 is Orchard SPECIAL, nothing to do with Supers.