Driving with the tailgate on your truck down will give you better fuel economy......

 

FALSE

Leave the tailgate up and add a piece of 4x8ft plywood tilted so that the high end is by the tailgate and the low end is at the front of the box.

NEVER drive the truck without supporting the bedsides or they WILL break their welds and you will have to live with floppy bedsides when you put the tailgate on and try to close it while pulling in on both bedsides at once to make the latches line up.

Want better aerodynamics? Buy a canopy or tonneau cover for the box.

 

Moved to proper forum. There are a number of threads on this topic here. The answer to your question is FALSE.

 

I also go with false or if there is an improvement it will be too small to notice.

 

True, I gain about 1 to 2 mpg on highway at 70 MPH depending on truck and did 30 years ago too. This bussiness about bed sides getting floppy from it is baloney. It is rust the weakiens them, not lack of tail gate support which does not "locK' into them anyway.

 

Well I can tell you this much Beer Cans in the back of a truck will get sucked out of the bed at 70-80 mph with tailgate up With tailgate down they don't move and stay towards the front of the bed. So as useing this as my own personal windtunnel test I would say False. There is very little air that hits the tailgate . Try this test if your brave enough. Sit in the back of your truck with your back aginist the gate and have a freind drive down the road at 70 mph and see how much wind hits you in the chest. I should also say safty equipment should be worn at all times (so you don't get hit by a stray beercan or two)

 

Several studies have been done on this subject. They all say false.

 

Not very good "studies" if you ask me because it does make a difference and likely even more so today's "sleeker" trucks.

 

Have you tested tailgate up or down personally? You say "likely" - these tests say, "this is what we found through testing."

 

SnoMan where not talking the Model T

 

No kidding? Neither am I. With the gate up it creates a big air drag dam behind cab that is not there when gate is down and it takes extra power and fuel to pull the dam through the air at speed.

 

With the gate up, a pocket of air is formed in and over the bed, so that air flows over the pocket and doesn't even hit the tailgate. With the tailgate down, you don't have this pocket and the drag behind the cab is greater. The difference is not the same on every truck cab/bed configuration, but it is proven that it certainly isn't any worse with the tailgate up.

 

Its was supposed to be funny . Just take a breath and chill for a bit . Its only a question . We know your not changing your mind on this and thats O.K. You drive with your tailgate down .It doesn't make you any less of a man. If it does they have pills for that too.

 

Everything I've heard says false. A little counterintuitive, but then, so are a lot of things.

Putting a canopy on also seems to pull the MPG down too, though. At least, it did in my Dad's 5.2 1500 Ram.

 

What about the louvered tailgates for 5th wheels/goosenecks?

I have a hitch so I wonder if those tailgates help with air flow and drag or just help when you have a trailer behind you.