I know fluids can be expensive, but for me, the hydrostat is NOT the place to save a buck or two. I've had JD's all my life, and I've owned other brands along with the JD's. I've learned that the fluid, changed every other year is not that big a deal, and I've yet to have a hydro go out. I had a pristine WH 141 auto, that was my pride and joy, even though I didn't really like mowing with it, as it had a 36" deck which took forever to mow with, but it was just a fun tractor. Well, in a moment of weakness, my neighbor talked me into selling it to him. He's one of those guys who messes with things until they don't work anymore, and sure enough he changed the hydro fluid, (it used 10w40 or 20w50 motor oil), but for some odd reason, he decided that if oil was good, tranny fluid would be better (at least that's what I'm thinking he used). It lasted not quite a whole summer before it stopped going uphill and finally quit moving altogether. Post mortem revealed a ruined hydro. JD's usually use HyGard, and that's what I use in mine. So, $40-50 bucks every couple years seems cheap for a good hydro.I don't know about Cubs, but the JD TuffTroq K91/92 can cost upwards to $4K, so I'm not gonna try to save a buck or two on fluid.