Remember though, I'm talking the hydraulic system and not the engine. I may be putting too much thought into this. When the skid steer was make, the motor oils were very basic back then. So I would think any type of 10w30 motor oil would work. My concern is damaging anything like seals, pumps, etc. but using the wrong oil. I think I am stuck on the mindset with Kubota. They are very particular on using SUDT when they state this in there manual. Now I have only owned and maintain fairly newer Kubota equipment, so that is my experience. BTW, to put a face with the name, this is the machine that I am working with. I put new tires on it last week. The old ones were in decent shape, but were badly dry rotted.
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