Can you get some pictures? Normally a tank, 4" piping and a slide valve makes the black system. The valve should be an easy replacement not sure what you mean by belly pan.
2000 F250SD SRW 7.3 Long Bed Extended Cab Air Bags
2014 Eagle 30.5BHLT
2007 Layton 245LF (sold)
196? Shasta 16ft
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