Simple advice:
>Don't go cheap on the fluids. (engine oil, hydraulic fluid, front axle). Use a tractor-branded oil like Case, New Holland, Kubota, or otherwise Amsoil ($$). Cost for 5 gallons of tractor-branded is around $80-$100. Amsoil $130-$190 depending on grade. I used 5w-30 at $185/5 gal. on my 15 gallon hot-running L48 TLB. (!!!)
>Use 70w-90 in the front axle.
>Change out the filters with Kubota or Wix (Napa).
>Even if the manual says change the filter only go ahead and change out the fluids this first time. You could have a UOA done on a bit of the hydraulic fluid to prove it to yourself. Then decide if you want to leave the old stuff in.