Myth busters

[Thorndike]

How about tonneau covers and truck caps. Do they do better or worse?

 

[BB_TX]

Here is <font color="blue"> an article about it. </font> Way down near the end it says a tonneau cover helps and gives some numbers.

 

[Thorndike]

BB, Good info on the tonneau. Just still wondering about the cap though. I'd always heard they would help out with mileage, and all but one of my trucks have had them. My wifes has the tonneau on her Ranger, still only gets 23MPG though, and never noticed a difference with or without it.

 

[CT_Tree_Guy]

Hey Eddie, I'm just wondering how the heck you find time to watch TV with all that you do! /forums/images/graemlins/smile.gif

All kidding aside, you are an inspiration to me, and I bet to many, many of us. Keep up the good work! (as if I had to tell you to). /forums/images/graemlins/smile.gif

 

[aardvark]

I documented the gas mileage on my Toyota Hilux for several years with and without a cap. It always got a couple mpg better without the cap. It was about 23-24 mpg with cap and 25-26 mpg without cap. I had the spreadsheet on my old computer which now has a bad video card. Maybe I can fire it up and copy the file before I trash the computer.

 

[Robert_in_NY]

The Nascar trucks have a rear spoiler that sticks straight up into the air to help catch some air still.

 

[BB_TX]

Haven't seen anything about caps. But it would seem the large flat back would have the same effect as the flat back of the cab sucking air behind it. Same principle as race cars drafting. When one gets close enough behind the other to eliminate that air space, they both end up going faster. One doesn't have to pull that air, the other doesn't have to push it. Don't know.

 

[Thorndike]

</font><font color="blue" class="small">( Haven't seen anything about caps. But it would seem the large flat back would have the same effect as the flat back of the cab sucking air behind it. Same principle as race cars drafting. When one gets close enough behind the other to eliminate that air space, they both end up going faster. One doesn't have to pull that air, the other doesn't have to push it. Don't know. )</font>
Ha!! So that's what those soccermoms are doing tailgating the snot out of ya!!!

 

[HGM]

Dont forget, that cap weighs about 3-500#'s. The weight alone could contribute to a mileage change on some trucks, especially a 4cyl Toyota. Another thing you may be able to look at is, what would the SUV equivelant of your pick-up get for fuel economy? You would likely be close to that, or at best between the PU and SUV.