engine, buy 6 quarts, you will need some fo rhte oil bath air filter. I reccomend 15w40 if temps aren't below 0'F though 10w30 is usually fine int hem. red tiger OHV engines generally can make up to 55 psi oil pressure if not all calpped out.. even worn ones usually run in the mid 30's
you will want to use UTF fluid meeting M2C134spec for the hyds..
trans and diffy can use that utf, OR 80w90 gl5 gear oil.
hyds has a dipstick on left rear inspection cover.
tranny has a level plug aft of right heel just above the running board.
diffy have a level check plug on the left rear side of the axle trumpet.
I don't have my manual ready, but the hyds can hold UP TO 3g, but doesn't need more than 6-8 qts unless you are running external hyds.
diffy and trans will be similar.. 8qts or so.. economics wise.. just grabbing a 5g pail of utf fluid ( store brand fine if meets specs ).. will probably get you there.... might need an additional gallon for top offs.. but check first..
trans drain is under trans.. is a bung...fill is by shifter.
hyds drain is a bung under hyds center section.. fill is a cap under lft leg under seat.
diffy drain is a pip plug under diffy, fill is a cap under back of seat / right but cheek.