Tailgate open or closed? Which is more fuel efficient?

Tailgate open or closed? Which is more fuel efficient?

By Russ and Tiña De Maris

It’s an age-old campfire discussion among RVers and pickup owners. Everybody wants to save money on gas — do you drive with the pickup truck tailgate open or closed? Up or down?

Driving with the tailgate closed would seem counterintuitive. After all, won’t the wind get “caught” by the tailgate and simply tend to slow you down a bit? Why not leave it open and let it flow freely? A story carried by Autoblog.com attempts to settle the issue. The results — if they cut across all lines of pickup truck design, tell you the answer. But it’s a big “if.”

Autoblog approached Ford Motors for the definitive test. Ford provided a 2015 F-150 — you know, the new “aluminum” aerodynamic pickup. The machine gains its notoriety for good fuel economy because of all that aluminum — it’s a great deal lighter than a similar “steel-sided” truck. But all that lightweight construction is easily wiped if aerodynamics are ignored. Tailgate open or tailgate closed — which is it?

Well, Ford has a secret built into their tailgate — a tailgate lip that acts as a spoiler. A wind tunnel demonstration Ford put on for Autoblog shows that keeping the tailgate up (closed) makes for less drag. Here’s why: The wind blasting over the top of the pickup cab needs a place to “touch down” and be redirected away from the truck. If the gate is left open, it doesn’t know where to go and, hence, tends to bunch up in the bed of the truck. Ford engineers say the same is basically true for all pickups — not just theirs.

One thing Ford says can improve aerodynamics even more — a tonneau cover will allow for even smoother wind movement, thus, increased fuel economy. Look at the autoblog.com post for more details. There are tons of tonneau covers available at Amazon.