Approx. % increase of mpg while adding bed cover
Thread Starter
5 Year Member
Joined: Apr 2015
Posts: 563
Likes: 70
From: TX
http://www.realtruck.com/tonneau-cov...e-gas-mileage/
Do tonneau covers really offer fuel savings?
Quick answer, yes they do. Ultimately a hard or soft truck bed cover increases the aerodynamics of your pickup thus increasing your fuel efficiency.
Open truck beds are a huge drag on your gas mileage. As air flows over the aerodynamic front end of your vehicle, it careens into your truck bed and produces opposite force to your truck. This could easily provide you with several miles of additional gas every single trip! Covering your bed up with a tight tonneau cover, either a hard or soft one, eliminates this tailgate drag.
How much will a truck tonneau cover increase gas mileage? tonneaus improve gas mileage
Tonneau covers do increase gas mileage, but by exactly how much depends on the truck and the brand of tonneau. Most tonneau bed cover manufacturers actively promote that a pickup cover improves gas mileage. This makes complete sense as less drag means better fuel economy. By closing your truck bed with a tonneau cover, you're reducing airflow and drag significantly while creating a secure storage environment for your tools, sports equipment and other belongings. However, most manufacturers are confident that a tonneau cover will pay for itself in fuel savings.
Some truck bed cover manufacturers offer Fuel Savings Calculators such as Access Cover or TruXedo. Pace-Edwards boasts an 11% increase in fuel economy. Access Covers claim you will save $225.00 per year in gas money.
Want more gas savings? Check out all RealTruck's gas saving products
Do tonneau covers really offer fuel savings?
Quick answer, yes they do. Ultimately a hard or soft truck bed cover increases the aerodynamics of your pickup thus increasing your fuel efficiency.
Open truck beds are a huge drag on your gas mileage. As air flows over the aerodynamic front end of your vehicle, it careens into your truck bed and produces opposite force to your truck. This could easily provide you with several miles of additional gas every single trip! Covering your bed up with a tight tonneau cover, either a hard or soft one, eliminates this tailgate drag.
How much will a truck tonneau cover increase gas mileage? tonneaus improve gas mileage
Tonneau covers do increase gas mileage, but by exactly how much depends on the truck and the brand of tonneau. Most tonneau bed cover manufacturers actively promote that a pickup cover improves gas mileage. This makes complete sense as less drag means better fuel economy. By closing your truck bed with a tonneau cover, you're reducing airflow and drag significantly while creating a secure storage environment for your tools, sports equipment and other belongings. However, most manufacturers are confident that a tonneau cover will pay for itself in fuel savings.
Some truck bed cover manufacturers offer Fuel Savings Calculators such as Access Cover or TruXedo. Pace-Edwards boasts an 11% increase in fuel economy. Access Covers claim you will save $225.00 per year in gas money.
Want more gas savings? Check out all RealTruck's gas saving products
Thanks all.
Senior Member
Joined: Jan 2013
Posts: 2,923
Likes: 711
From: Calgary, AB
^except that this says exactly the opposite of what other "studies" have shown...
In other words, it's like religion, believe what you will, there is no solid proof either way...
try opening your slider window with wood dust or snow in the bed, and you'll get a very clear (and messy) demonstration of the air bubble in the box...
EDIT: a shop that sells tonneau covers shouldn't be expected to say anything different...
In other words, it's like religion, believe what you will, there is no solid proof either way...
try opening your slider window with wood dust or snow in the bed, and you'll get a very clear (and messy) demonstration of the air bubble in the box...
EDIT: a shop that sells tonneau covers shouldn't be expected to say anything different...
Senior Member
Joined: Mar 2015
Posts: 184
Likes: 16
From: Pickering, Ontario
Ah naysayers galore... You want more?
http://www2.sema.org/Main/SemaOrgHome.aspx?ID=52546
Another, thier conclusion:
On average, it is safe to say that a tonneau cover will reduce the coefficient of drag by
5.73% (based on the thirteen different tonneaus we tested.) We tested a variety of covers, from
soft vinyl, to folding two-piece to fiberglass. As indicated earlier, other tests would need to be
conducted in order to determine the exact effect on fuel economy. Aerodynamicists often say that
a 10% improvement in aerodynamic performance is good for a 2-3% improvement in gas
mileage, based on an EPA road speed of 48 mph. Therefore, an improvement in Cd of 5.73%
could account for a 1.8% improvement in gas mileage. The results of this test are positive for
tonneau manufacturers. With fuel efficiency on the minds of consumers and automakers alike,
it’s great to see that aftermarket products can help improve fuel economy and will keep pickup
truck enthusiasts in their pickups.
http://www.trucktestdigest.com/PDFfi...uStudy2007.pdf
Score 3 against 1 so far saying they do.
LOL
http://www2.sema.org/Main/SemaOrgHome.aspx?ID=52546
Another, thier conclusion:
On average, it is safe to say that a tonneau cover will reduce the coefficient of drag by
5.73% (based on the thirteen different tonneaus we tested.) We tested a variety of covers, from
soft vinyl, to folding two-piece to fiberglass. As indicated earlier, other tests would need to be
conducted in order to determine the exact effect on fuel economy. Aerodynamicists often say that
a 10% improvement in aerodynamic performance is good for a 2-3% improvement in gas
mileage, based on an EPA road speed of 48 mph. Therefore, an improvement in Cd of 5.73%
could account for a 1.8% improvement in gas mileage. The results of this test are positive for
tonneau manufacturers. With fuel efficiency on the minds of consumers and automakers alike,
it’s great to see that aftermarket products can help improve fuel economy and will keep pickup
truck enthusiasts in their pickups.
http://www.trucktestdigest.com/PDFfi...uStudy2007.pdf
Score 3 against 1 so far saying they do.
LOL
Senior Member
Joined: Sep 2014
Posts: 198
Likes: 31
Ah naysayers galore... You want more?
http://www2.sema.org/Main/SemaOrgHome.aspx?ID=52546
Another, thier conclusion:
On average, it is safe to say that a tonneau cover will reduce the coefficient of drag by
5.73% (based on the thirteen different tonneaus we tested.) We tested a variety of covers, from
soft vinyl, to folding two-piece to fiberglass. As indicated earlier, other tests would need to be
conducted in order to determine the exact effect on fuel economy. Aerodynamicists often say that
a 10% improvement in aerodynamic performance is good for a 2-3% improvement in gas
mileage, based on an EPA road speed of 48 mph. Therefore, an improvement in Cd of 5.73%
could account for a 1.8% improvement in gas mileage. The results of this test are positive for
tonneau manufacturers. With fuel efficiency on the minds of consumers and automakers alike,
it’s great to see that aftermarket products can help improve fuel economy and will keep pickup
truck enthusiasts in their pickups.
http://www.trucktestdigest.com/PDFfi...uStudy2007.pdf
Score 3 against 1 so far saying they do.
LOL
http://www2.sema.org/Main/SemaOrgHome.aspx?ID=52546
Another, thier conclusion:
On average, it is safe to say that a tonneau cover will reduce the coefficient of drag by
5.73% (based on the thirteen different tonneaus we tested.) We tested a variety of covers, from
soft vinyl, to folding two-piece to fiberglass. As indicated earlier, other tests would need to be
conducted in order to determine the exact effect on fuel economy. Aerodynamicists often say that
a 10% improvement in aerodynamic performance is good for a 2-3% improvement in gas
mileage, based on an EPA road speed of 48 mph. Therefore, an improvement in Cd of 5.73%
could account for a 1.8% improvement in gas mileage. The results of this test are positive for
tonneau manufacturers. With fuel efficiency on the minds of consumers and automakers alike,
it’s great to see that aftermarket products can help improve fuel economy and will keep pickup
truck enthusiasts in their pickups.
http://www.trucktestdigest.com/PDFfi...uStudy2007.pdf
Score 3 against 1 so far saying they do.
LOL
A even simpler test would be to test it in real life. I suspect that they did and real world usage didn't support their theory, so they just ignored it.
Senior Member
Joined: Mar 2015
Posts: 184
Likes: 16
From: Pickering, Ontario
Couple of things stand out. For one, this study was done by SEMA, which as we all know supports accessory makers. Not exactly impartial. Why go through all of the hassle of testing in a wind tunnel and not following up with a simple road test to see how a cover REALLY impacts MPG? Instead they state "In order to determine how coefficient of drag translates into fuel efficiency (MPG), a simple equation is derived".
A even simpler test would be to test it in real life. I suspect that they did and real world usage didn't support their theory, so they just ignored it.
A even simpler test would be to test it in real life. I suspect that they did and real world usage didn't support their theory, so they just ignored it.
Senior Member
Joined: Sep 2014
Posts: 198
Likes: 31
A road test would be even more unpredictable or inconclusive. Depends on driving conditions, driver, wind, temperature blah blah blah. I think it's safe to say that it doesn't hurt gas mileage and may actually improve it. At least that's what I think. In the end I don't really care one way or another and will buy one because I want to keep things dry and safe. If there is a gas mileage improvement then great if not ..meh.. who cares.
I recently installed a cover and my mileage was impacted by exactly zero. I drive the same route to work each day and my normal mileage was 17.8 before the cover and 17.8 after. Nothing changed.
Senior Member
Joined: Mar 2015
Posts: 184
Likes: 16
From: Pickering, Ontario
Not really, if you do multiple tests consistently and average the results out you will get a far better real world idea vs. just trying to guess at how the drag coefficient really impacts MPG.
I recently installed a cover and my mileage was impacted by exactly zero. I drive the same route to work each day and my normal mileage was 17.8 before the cover and 17.8 after. Nothing changed.
I recently installed a cover and my mileage was impacted by exactly zero. I drive the same route to work each day and my normal mileage was 17.8 before the cover and 17.8 after. Nothing changed.
