Possible to add a grey water tank?

[Apache_Camp]

My 1975 Argosy has a tiny factory black water tank that the toilet sits directly on top of. It looks to me as though my gray water empties into the black tank, but the bottom skin is still on the trailer so i'm not quite sure whats up....

[Aage]

By 1975 (1974, actually), all Airstream branded TTs had a gray water tank, but I can't say for sure about Argosy models.

But to see how, use the Google option in the Search function. You'll see it in the dark blue line near the top: search for "add gray water tank" and you'll get lots of hits.

[azflycaster]

You should have two tanks. See how many dump valves you can find. My 75 TW has one in the bumper compartment (black) and one next to where the slink hose connects (grey).

[Apache_Camp]

Just looked. Your right, it has 2 dump valves, didn't see the one in the very back. 1 is stuck shut (guessing its the gray tank) the black tank valve seems to work ok.