Old Kubota question

[HatchetFF]

The old 70s M4500DT has sat for a couple years, went to start it and all the hydraulic/transmission oil drained out. Manual calls for SAE 80 but I don't think it takes 8 gallons of gear oil, I think it's referring to a type of transmission/hydraulic oil. Any advice on what is the modern equivalent of what 40 years ago was called SAE 80?

 

[nybirdman]

I would call a dealer for advice;Messicks in Pa. may have an answer.