Bobcat 15C auger seals.

[mogman]

Back in the day the 1990s and through early 2000s Bradco was the manufacturer of skid steer back hoes and augers, the planetary reduction drive auger as we see in the above picture I believe used gear oil in th the lower portion, I would think there would be a vent on the housing of the planetary, they also made a chain drive unit and it was just greased at the bearings.

Nope, it uses the hydraulic oil, as I have said several times the motor has no seal, the body of the motor is somehow valved in such a way that it is connected to the return side no matter which way the motor is turning, the excess that bleeds from the motor drive to the body of the motor fills the lower housing then is returned via the return line. The only shaft seal it the entire unit is in the lower housing.