Interesting point we have here......I have been meaning to email walker about this since the fall (have to before the spring). I bought what I needed (according to the maunual) to change all the fluids in the fall. I drained the hydros and went to fill with the 5w-30 that the manual says to use, and the sticker on the resevoir says to use 15w-50.. Since I already had the 5w-30 I used it. Thanks for the reminder......I am going to email them now. I will post back when I get the results.
jeffyr
PS LawnPro in NC : I bought mine used and called Walker and they sent me the tractor manual, deck manual, and service manual for free. Give it a shot.