Skypup, I guess I'll have to move to your State. Maybe they have some good dealers there. My dealer has the best rep within say 40 miles, and we have a number of Kubota dealers in that circle. I will call around next time to see what the others are doing though as far as dosing the hydraulics. I'm not even defending my dealer, they are just the best here according to everyone I've spoken to. There is allot more to a dealer than just fluids. They will get an education on that as you will see below.
I'll try and rein in the confusion you caused some with your comment that Kubota doesn't spec engine oil. Kubota only lists the reccomend weights and API ratings. On my 3130 the API can vary depending on the sulfur content of the fuel.
I stumbled across something that does add to or bolster your case, and it would be remiss of me not to bring it to this discussion. Surprised you didn't bring this to my/our attention. At the end of the periodic maintenance section of my 3130 manual there is a note, with wording to the effect, that SUDT is the recommended fluid for better protection, etc.. I'm on lunch so I don't have the manual here to do a verbatim, pg. 65 maybe. I had totally missed that. So I retract my comments that both fluids are "recommended" for my machine. They are both "acceptable". Kubota would prefer we use SUDT in the 3130's and I assume most other models. They state that.
Does this mean you won the UDT/SUDT comparison debate? /forums/images/graemlins/shocked.gif To a degree it does. /forums/images/graemlins/smirk.gif Does Kubota advise against using UDT as you do? No, but they clearly state that it offers better protection. So they weigh in on your side.
I was not too suprised by the flow separations in your attached graph. Basically what I would have expected, except I thought the merge would be closer in time. I didn't see the ambient or fluid temps noted though. I'd be curious to know that if you do.
Been fun!
Regards,