In college my friend had a tubular bumper made for his Samurai and the welder put a schrader valve on it. It allowed him to put compressed air in it to refill his tires after he went on the sand dunes. I know they make portable tanks to carry but I was wondering if anyone has ever heard of a tank that could be installed under the Suburban. I'd like it to be able to hold enough air for all four tires. Links or thoughts?