You are making a VERY EASY issue, VERY difficult.
the hyds, rear end, and tranny are all seperate sumps.
the hyds needs a utf / hydraulic fluid.
the tranny and rear end, need a utf or gear oil. best gear oil is a modern 80w90 gl4/gl5.. commonly available.
thus.. you can use UTF in all 3 sumps.
if you are in the arctic area, use the utf.
if your inner hyds to diffy seals leak.. use the utf.. etc..