Dana 44 closed knuckle spindle seal?
 

I have a 69 GMC K2500 with a dana 44 closed knuckle front axle. I just pulled the front wheel bearings and found gear oil in the wheel bearings. I believe its from the 140w gear oil in the closed knuckle. Is there a seal in the spindle to prevent this or is this normal lubrication for the wheel bearings?