Do Tonneau's actually improve MPG's?

Just wondering..

 

I noticed a marginal increase. Maybe 1 mpg on a good day. It won't be be worth the money for an increase in MPG but luckily they are useful in other ways as well.

 

I offer no answers or help, I'm interested in that same information.

 

Same gas mileage before and after installed, 16-18 highway.

 

Nope, but still glad I got mine.

 

No down side so far - easily removable and no noticeable hit to mpg.

 

I did some MPG readings after I put mine on. No measurable difference commuting (18 miles one way) and in everyday driving.

 

absolutely not!

 

Nope.

 

agree - no difference at all

 

I think it is marginal, maybe 1 mpg.... I got mine to keep snow out of the bed in the winter and to keep stuff dry, especially for family trips.

 

Not for me. On, off, doesn’t matter. Best way for me to improve mpg is to put my air dam back on, drive like my kids live here, and avoid 90/94.

 

If there is, it's very minimal. Not a marketing point for sure. But then again, most people don't buy a tonneau cover for MPG savings.

 

Myth busters proved that trucks get the best mpgs by letting the air flow over the top of the truck into the bed. Taking tailgate off, changes this flow as does a tonneau

 

Some studies say yes, some say no. Some owners say yes, some say no. I’d say get one for other reasons before MPG if you like those reasons, but not specifically for gas mileage.

 

The theory is that without a tonneau cover the air begins to swirl in the bed, which causes a "bubble" of air for
more air to move over. If you have a tonneau the air hits it directly, causing some down force. True or false, I can't say.
In my mind, without a tonneau the air is constantly impacting the tailgate, but I'm not a scientist, and I don't play one on TV.

Red = no tonneau, initial air flow, and creation of air "bubble".
Green = no tonneau and air flow after initial "bubble" creation.
Blue = with tonneau and air flow hitting the cover.

 

Gee, wonder why?? K&N also claims some ridiculous power gains as well.

 

X-Tang says 10% mileage savings. That would have been 2 MPG. I estimated I got 5% or 1 MPG better. Will take a long time to pay for itself but makes hauling stuff in the bed a lot better (mostly rain proof and out of sight) and looks good.

 

I noticed a gain on the highway. driving the exact same stretch of road multiple times a year I can say it increased by a bit.

 

I used tonneau covers on two different trucks and never saw much difference either way.