Re: The Shell Game
From all I have read or heard the empty bed with tailgate up is the best way to travel in a pickup for best mileage. It seems in air tunnel tests the air flows over/above the empty bed because of the up tailgate. When the tailgate was removed there was more air turbulence and friction. The 5th Wheel tailgate all of us 5er owners use with the V and louvers is not as good as the stock tailgate for good mileage.. However, after you hit the stock tailgate with a King Pin once or twice you use the V tailgate.
However, to answer your question, I don't know about the dynamics of the air flow with a trailer tagging along behind. The shell may divert the air up and over the TT or it might direct it right into it.
I do know that most of the owners of the wings on top of the pickup cab that supposedly direct air over the 5th Wheel or TT, claim that it doesn't make much difference as far as mileage goes with it (wing) or with out it.
Bottom Line: I guess my ramblings didn't add much as far as your question goes. :clown: