Confirmed: Tonneau Cover Not Great for MPG+
#16
Well, I went to Ohio from the Washington, D.C. area, and at speeds of 65-75 mph, my Roll-X, in conjunction with premium fuel, netted me 3 mpgs better than prior trips.
And that's running in summer, with the A/C on the whole time, versus winter.
While I also didn't buy the cover for mpgs (mostly to protect luggage), it's been good to me so far.
-John
And that's running in summer, with the A/C on the whole time, versus winter.
While I also didn't buy the cover for mpgs (mostly to protect luggage), it's been good to me so far.
-John
I plan to get a Bakflip F1 for my '12 SCREW to protect the bed first and foremost.
#17
that is about what I have been seeing in test runs with my homemade experimental tonneau cover: I have been getting results that show anywhere from 0 to 1.0 mpg improvement when I have the cover mounted on the truck, depending on the cruising speed during the test.
I am looking at getting a BAK G2 cover, for the weather and "prying eyes" security issues. I like the hard suface and the flush mounting.
But I really wanted to try to develop a good answer for the mpg question as well. I have come to a conclusion that Ford may have, in the 2009-2012 models at least, sufficiently modified the shape of the truck cab so that cruising aerodynamics form even more of a sort of "air pillow" in the open truck bed, than in earlier trucks. In a lot of situations, the addition of a tonneau cover to these latest F-150 models might just not significantly improve much on the qualities of that built-in "dead air" space.
#18
#19
Anechoic chambers just prevent RF signals from reflecting back off the chamber walls. They don't keep them out. Most all sensitive measuring devices are RF/EM shielded to prevent interference anyway. You want an RF Anechoic chamber if you're testing the radar signature of model aircraft, not when testing aerodynamics.
#20
I found this little column that had some information from Ford and Dodge engineers. Looks like 1mpg increase is about the best you'll do with a Tonneau cover in the real world.
http://www.trucktestdigest.com/TTDfe...teUporDown.htm
Anechoic chambers just prevent RF signals from reflecting back off the chamber walls. They don't keep them out. Most all sensitive measuring devices are RF/EM shielded to prevent interference anyway. You want an RF Anechoic chamber if you're testing the radar signature of model aircraft, not when testing aerodynamics.
http://www.trucktestdigest.com/TTDfe...teUporDown.htm
Anechoic chambers just prevent RF signals from reflecting back off the chamber walls. They don't keep them out. Most all sensitive measuring devices are RF/EM shielded to prevent interference anyway. You want an RF Anechoic chamber if you're testing the radar signature of model aircraft, not when testing aerodynamics.
Built for testing antenni and precisely measuring radio wave deflection. All instruments for measuring are placed inside the chamber to prevent any electrical or wavelength interference, so very precise measurements can be made without distortion.
All the computers in the US Pentagon are housed inside Anechoic Chambers that shields from outside interference.
Guess I shoulda said 'Shielded Anechoic Chamber'.
Last edited by High-ster; 07-06-2012 at 08:29 AM.
#21
Thanks MrEvil,
that is about what I have been seeing in test runs with my homemade experimental tonneau cover: I have been getting results that show anywhere from 0 to 1.0 mpg improvement when I have the cover mounted on the truck, depending on the cruising speed during the test.
I am looking at getting a BAK G2 cover, for the weather and "prying eyes" security issues. I like the hard suface and the flush mounting.
But I really wanted to try to develop a good answer for the mpg question as well. I have come to a conclusion that Ford may have, in the 2009-2012 models at least, sufficiently modified the shape of the truck cab so that cruising aerodynamics form even more of a sort of "air pillow" in the open truck bed, than in earlier trucks. In a lot of situations, the addition of a tonneau cover to these latest F-150 models might just not significantly improve much on the qualities of that built-in "dead air" space.
that is about what I have been seeing in test runs with my homemade experimental tonneau cover: I have been getting results that show anywhere from 0 to 1.0 mpg improvement when I have the cover mounted on the truck, depending on the cruising speed during the test.
I am looking at getting a BAK G2 cover, for the weather and "prying eyes" security issues. I like the hard suface and the flush mounting.
But I really wanted to try to develop a good answer for the mpg question as well. I have come to a conclusion that Ford may have, in the 2009-2012 models at least, sufficiently modified the shape of the truck cab so that cruising aerodynamics form even more of a sort of "air pillow" in the open truck bed, than in earlier trucks. In a lot of situations, the addition of a tonneau cover to these latest F-150 models might just not significantly improve much on the qualities of that built-in "dead air" space.
@Nimrod - somewhere on Ford's web site, they have videos showing how the back of the cab is designed to direct airflow to the top of the tailgate.
-John
#22
Well, I went to Ohio from the Washington, D.C. area, and at speeds of 65-75 mph, my Roll-X, in conjunction with premium fuel, netted me 3 mpgs better than prior trips.
And that's running in summer, with the A/C on the whole time, versus winter.
While I also didn't buy the cover for mpgs (mostly to protect luggage), it's been good to me so far.
-John
And that's running in summer, with the A/C on the whole time, versus winter.
While I also didn't buy the cover for mpgs (mostly to protect luggage), it's been good to me so far.
-John
#26
I read an article a few years ago in a magazine , Truckin I believe, about teh pick up CART was using for a pace truck. They did bunch of wind tunnel and real world testing on different configurations. They ended up with Tonno that covered approximately teh rear two thirds of teh bed, with the front third open. This resulted in the lowest CD for the turck, Chevrolet ?, tested. They also stated that lengthening, or shortening the cover by a few inches made a huge difference in drag.
Looks like it might have had to do with seats as well.
http://rumors.automobilemag.com/cham...es-134522.html
Looks like it might have had to do with seats as well.
http://rumors.automobilemag.com/cham...es-134522.html
Last edited by Glen R; 07-06-2012 at 12:36 PM.
#27
#29
I'm just puzzled why: a) you use the word "confirmed" as if your plywood contraption along with the trip computer outweighs all studies done by anyone to date, and b) why is doesn't say "confirmed, tonneau covers improve mileage more or less about what has been claimed by most people all along". I opened the thread expecting to see a study that showed the tonneau to make MPG worse.
#30
I read an article a few years ago in a magazine , Truckin I believe, about teh pick up CART was using for a pace truck. They did bunch of wind tunnel and real world testing on different configurations. They ended up with Tonno that covered approximately teh rear two thirds of teh bed, with the front third open. This resulted in the lowest CD for the turck, Chevrolet ?, tested. They also stated that lengthening, or shortening the cover by a few inches made a huge difference in drag.
Looks like it might have had to do with seats as well.
http://rumors.automobilemag.com/cham...es-134522.html
Looks like it might have had to do with seats as well.
http://rumors.automobilemag.com/cham...es-134522.html