Juan Cortes two different things. Gear oil is 80/90 weight and drain is located at bottom rear of transmission. Fill hole is on the upper right side a bit hidden behind the guards.
I got a used 2005 Baja Dune 150 went to change the oil that dribbled out black oil. Probably never been changed. But I tried to put oil in and coming out through the filler can't even get 3 oz in what's up with that?