does having your tailgate off on longer trips help your gas mileage or not

 

no

 

MythBusters did this on one of the episodes. It does nothing according to there research and tests. I for one beleive them. I'll take practicallity over science any day.

 

No, it does not help, however a bed cover, fiberglass topper, or a tonneau would indeed improve gas mileage.

Mythbusters did in fact test this, and they believed it did nothing to help. The results of that episode actually showed having it on the truck and in its normal position did more then taking it down or leaving it off.

 

I saw that Mythbusters too, and thought their methods were not very scientific (driving two trucks, one with tailgate up, one down until one runs out of gas). But the little wind tunnel thing they did with water and oatmeal was interesting. I have tested this on my own truck, and found no noticable difference in either direction. I have heard others agree that a bed cover does make for a slight mpg increase.

I'm sure Hank will jump in here with his mpg/aerodynamics post that takes 3 days to read.

 

That's exactly what I was thinking [8D]

As stated...no, it doesn't help. And in some cases it can actually take downforce away from you truck by giving the wind/air something else (if the tailgate is down) to lift on.

 

def doesnt help- ive tried both ways on several tanks of gas and there is absolutely no difference whatsoever

 

i know im not gonna hear the end of this but when i have it down i do get better mileage i did see the mythbusters too i wish they woulda dun the test on more than 1 trip but i dont wanna start an argument so here is what i say you do mossy765, if you wanna know if its gonna work for you because i know your gonna get some saying it duz and some saying not, wen you go on your next trip keep track of your mileage go one way with it up and one way with it down (its best if you can do a round trip with it up and the same round trip down) and see where you get the best mileage and deside for your self

 

I do get better gas milage now that i put on the Soft Toneau cover. but 1 thing I did feel Before the Soft Toneau Cover was the way the truck goes down the road with the tailgate up or down. I feel more drag and less throttle response with the gate up. Enough of a difference that when I would be on the interstate I could actually tell without looking if my gate was up or down just by the way I could get up to speed to pass someone. So Yes with that in mind I know I used more gas with the gate up. But like they said get a toneau cover, no more issues.

 

No a bed cover or fiberglass topper does not improve mileage either, actually it might even hurt milage because of the weight of it. If the bed cover is light enough then yeah, it may help.

As for the tailgate thing... someone can do their own test on it and let us know... (I live in the flat lands, nearest hill is 40 miles from home otherwise i'd do it) find a hill, long easy grade is good enough, and make a run up the hill in OD and see how much (if any) speed is lost climbing the hill, then do the same test with the tail gate down and compare the 2 runs. IF there is no difference, then there should be no difference in gas milage... if there is, then you may see some mpg improvement on the highway.

this test will also show you before and after performance gains on mods since it acts as a bigger load on the motor when your on a hill.

edit: oh yeah, another thing to mention... your gas milage is going to be affected by how much HP it takes to keep your truck moving at whatever speed your driving at... if the truck is either lighter, has less drag or has more hp at that rpm, your gas milage should improve. reason being is you have less throttle, and a greater vacuum signal to the pcm.