Wolfe10,
Thanks for the ideas. They are worth checking out. The only hitch I can think of is that all those mentioned also have warning lights on the dash and none of these light up when the audible alarm sounds. Nevertheless, I'm probably going to end up crawling around the engine compartment looking for cracked seals on connections to sensors, chaffed wires and the like. Someone also recently mentioned bleeding the air tank (which I did recently) and something about the possibility of water in the diesel fuel separator. If anyone has thoughts there........keep the ideas coming. Thanks !!