Know this sounds crazy, but we are really looking over our recent purchase and doing some fine tuning since it's a 2009. WHY is there only ONE dump valve??? We are use to Grey and Black valves and have never seen anything like this. We were both down on the ground looking around and trust me, that is NOT easy because we can't get back up!..Anyone else have only ONE valve??? Am I dumping both grey and black at the same time???