Here is a rear suspension air system diagram that Richard Entrekin & I put together so we could understand the air flow in the rear suspension. This schematic applies to coaches that have one rear six pack and covers years from the 90s into the 2000s. An important fact that is not clear in the schematic is that the tag axle air tank is actually two tanks that are separated on the inside. We hope this will help others troubleshoot their systems.
Thanks for this guys! Its very timely. I have a weird problem where the coach will stay level most of the time with the key off. It always stays level when I am in travel mode. But....when I lower the coach down ... say to make it level for an unlevel site....the coach will lay all the way down and list to the right. With this diagram, I bet I can figure out where the issue is.