[Richard]

As @"rheavn" would tell anyone, finding and fixing air leaks is not easy. Unlike electrical problems where we can measure at many points in a system, we are blind to what is really going on other than losing air pressure somewhere.

So we quite often have to "break into" the air system plumbing to determine where the problem lies. Many of us have built or collected a small assortment of air line fittings, gauges, and valves to make this a routine exercise.

The methodical approach of isolating and testing works. The random replacement of fittings, valves, and cylinders is expensive and does not produce satisfying results.

That being said there are a few areas that commonly cause air leaks of consequence. The electric valves that operate the dump valves, a hole in a slide seal, the bode door system, connections at the air ride seat, and the microphor potties are quick places to check.

If you haven't you might want to study this thread http://newellgurus.com/showthread.php?tid=2690 and this one http://newellgurus.com/showthread.php?tid=2677&page=2

And the best one of all " @rheavn can you find your most excellent thread on the system and the air leak isolators? I couldn't find it in a quick search this morn."

That thread should be a sticky at the top of air systems category.