Quote Originally Posted by Hotboat View Post
Good thread and great reminder.

I have wet bearings on my trailer. Its been a couple years since I've checked the levels. Albeit I don't tow very far and I haven't noticed any leaks, but you just never know.
Oil bath hubs are a tough one. They are designed to require minimal maintenance and perhaps due to this they are often neglected. They are a great system but in my opinion don't really belong on boat trailers. The problem is boat trailers sit for an extended period of time. Since the hub is only about half full of oil the seals have a tendency to dry out above the oil level. You can look when the boat is parked and not see any leak but as soon as you tow the dry half of the seal can fail causing oil to leak out. Most people check their trailers before leaving home. So what happens is you give it a good look, don't see any signs of a leak, and proceed to tow your boat to the ramp. Launch the boat play all day and go home. Oil leaks out on the road and by the time you check it again before your next trip the evidence is gone. This is made worse by the fact that after a season or two the oil level inspection window on the outside of the hub is often discolored making it difficult or impossible to check the level.
Don't get me wrong, I know there are a lot of advantages to the oil bath hub. It just needs to be inspected and maintained like any other part of the boat and trailer.