Recently purchased a 52" Toro T-Bar classic hydro (I realize this isn't the most popular mower with ya'll). My question is this, the manual and the hydro tank say to use mobilfluid 424, the dealer and the newer-style Toro models say to use Mobil 1 15w-50. The dealer told me it says 424, but they use 15w-50 'cause it works fine. I noticed that my mower has BDP-10L pumps, where the newer-style (pistol grip) has the BDP-10A pumps, is this why different fluid is called for and can I safely use the mobil 1 15w-50. Anyone else have a mower with BDP-10Ls with some hours on them and use 15w-50? This thing costs a lot and I don't want to screw it up, I'm new to hydro.