Of the many things learned during POG IV was to keep your coach's air system c-l-e-a-n. From a preventative maintenance point of view, the entire air system, from the engine through the tanks should be drained of water and any residual oil at least once a year. It is normal to accumulate same during the course of use, according to the pros.
Well, guess what.
Here at Camp Prevost in Nashville is a fella with a 96 coach, and to the best of his knowledge, has never had his air system cleaned since new. He's here because the front end of his coach has dropped, has already spent a bunch of money elsewhere swapping out valves without a fix. When the tech at wherever-he-was-along-the-way, pulled an air valve, the owner noted the line was filled with gunk.
Armed with the new knowledge from POG IV, asked him the question and he said, "I betchya that was the problem. Maybe all my valves and air dryer are filled up!" Maybe so.
Undoubtedly, as folks drift back home this may be a thread of more merit than I can contribute, but it sure makes sense to put the air tanks/air dryer on the list for the annual maintenance (at least) to stay ahead of potential problems down the road.
Thanks to the experts for coming into POG IV and teaching all of us so much!