We have four Kubota tractors on our farm. A L2900, a BX2230, and M105X, and a M125X.
We are using Mobil Delvac 1 ESP 5W-40 or Mobil TDT 5W-40 in them.
I have tried other oils, Rotella T6, Triple Protection, Valvoline All Fleet, and while they are good oils, I like the way the tractors are running with the Mobil oils. With the L2900 and BX2230, it is really noticeable. Smoother and quieter.
With the Mobil rebates going on, it is a win-win!