yanmar 180d

I am working on a ym180d , Can you tell me what type of oil is used in the gear box?

I have a very nice 180D, 4X4, new paint, new tires, 875 actual hrs. This is a domestic market Yanmar, so parts are readily available. Considering adding a loader to it. Have been quoted $2,800 for an SMC loader & have tried out an SMC on a JD & found it to be acceptable--actually, pretty...