For the 50 hour, as I recall its BOTH the engine and tranny oil and filters, and then just a handful of checks on some other stuff. $250 is going to be about average for this, you have about $100 in materials (2 filters, 1 gal engine oil, 2.5 gal SUDT) plus about two hours of shop labor to change everything out and go over the machine. </P>
I second sticking to SUDT, if you want to savea few bucks maybe look at an aftermarket filter, but I'd really recomend sticking with Kubota's tranny fluid. The RTV drives very different even with new oil vs old oil, If youuse somthing thats even alittle off of spec I am sure your going to be able to tell the difference.</P>
As for Warrenty, this is bull. They can't enforce warrenty coverage based on a particular fluid unless they provide it to you at no charge, otherwise you can use whatever you want that meets the specification (there are SUDT equilivant products, but I'm not sure they are any cheaper). </P>
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