1984 john deere 111h hydrostat oil

[wheats71]

hi there just joined the forum i just boght my first jd mower a 84 111h
i have done regular service on it but would like to change hydro fluid but i have no idea what to use
i have been told htdraulic oil, motor oil and type f tranny fluid
what would be the proper answer ?
thank in advance

 

[JimsRepair]

Use 10 W 40 engine oil.