Jon,

I could not build air pressure when the tag was lifted. Any time the tag was up, the aux air compressor would not quit running. So I put shop air on the valve in the front compartment and walked around until I heard air. Sprayed soapy water and the tax axle lift chamber made big bubbles. See this link for the cause.
http://forum.prevostownersgroup.com/...ead.php?t=4094