Slow draining front tanks

[stengels]

We've not had a problem with ours. I wonder if the tank has shifted some, causing it to have a different angle, not allowing the tank to drain properly, or as well. I always drain my front black, then my rear black. I follow that with front gray and then back gray. I may have a little more force with the rear tanks (as you know, the tanks drain nearer the rear tanks). We love the set-up of the 3900 FB and wouldn't exchange it for anything at this time.