Have a versatile 575 4wd tractor with a cat ta 22 powershift transmission. Factory fill is shell donax td which I believe is to-2 and cat recommends a oil specified at to-4. Have talked to cat and they recommend cat brand MTO 10w30 of course because they are selling it. Talked to a major transmission rebuilder and he said they never recommend a multi-viscosity oil in a powershift sump transmission that does not have a shared reservoir with the hydraulic system. He stated they used mobiltrans HD SAE30 in these transmissions. So I'm at a loss and looking for some direction. Cat said that this mobil oil is to-4 rated and shouldn't be a problem. So what is the best oil to use?
