Mike B, I had gear oil in the box for the past couple of years. Always a triickle and I ran out of rags trying to clean it up. This time I tried some hub oil by Lucas. A little thicker than gear oil and the "stops leaks" on the bottle caught my eye. Similar trickle. Been reading other posts that talk about self leveling grease. Some say this does the trick. Others say theirs still leaks. Would rather take a beating than fish that box and steering shaft out and back in again while trying to keep some paint on it.