When I bought the trailer the fresh water vent hose dropped down out of the underbelly and siphoned out the tank as you drove down the road. It would drop the level by at least 1/3, sometimes more. Ha...
Our FR Wild Cat did the same thing - here is the fix: Inlet
This water fill inlet moves the vent end up to a spot so high that the water can never spill or siphon out. It takes some minor surgery with a jig saw but it's well worth it. Worked great for us!
