I do agree in not mixing every brand of oil you come across in the hydrostats of these units. Pick an oil, and stay with it, be it the JD, or the CNH Hy-tran Ultra.

Red machines came with the Hy-Tran in them.

I ran the JD Hy-Guard when I had my Patriot XL.

Almost forgot, you need to refill the hydraulic tank "thru" the plug in the filter housing, on top of the tank. If you don't want to be all day at it, you'll need a pump with a hose that will thread into that plug hole. Oil needs to be filtered as it's put into these units.