[77newell]

My 93 coach arrangement may not apply to your coaches but here goes; having traced the connections when I replaced the main air dryer, the output from my 120v Gast compressor is plumbed to the inlet of the main air dryer. My only concern with removing the Gast's dryer would be what happens to the moisture on its way to the main dryer in freezing weather. Otherwise it's just making the main dryer's job easier.