I just got a woodchipper. It has a hydraulic feed consisting of a gear pump and hydraulic motor. Plus speed and direction control. A simple manual system, no servos or pilot valves. Manufacturer recommends ISO 32 hydraulic oil. Is there any downside to using a tractor transmission fluid that's designed for the common sump? (that feeds the transmission & tractor hydraulic system) The key difference is the hydraulic motor of the chipper. And the transmission & brakes of the tractor. Many tractors have a gear pump to pressurize the system. Yet, some farm implements (planter, baler, etc. ) use hydraulic motors that run from the tractor hydraulics. I wonder if the friction modifiers for the tractor clutches & brakes causes an issue with the hydraulic motor swash plate. Your thoughts and experience is appreciated.
You should be just fine. I know of several outfits that run tractor fluid in excavators and they are still going. (not something I would do) and some hydrostat systems recommend tractor fluid (Depending on manufacturer)
RZ … The issue is availability. Seems all the local stores have tractor fluid of various obsolete specs (like Deere J20C ) but not a true ISO 32. Happy homeowner with an old Ford Jubilee is pouring what ever oil he gets into it... while most leaks out As you said, likely fine but for a little more effort & $ I wonder if getting hydraulic oil without the tractor specific additives is worth it.