Ford air tunnel testing: tailgate myth and tonneau cover (aerodynamics / MPG)

[colinl]

This assumes all driving is at highway speeds. The aerodynamic drag will not be the same at all speeds and increases with the square of the speed. In fact there may be some mileage decrease a very slow stop-n-go driving due to the added weight of the tonneau cover and the minimal aerodynamic drag at these speeds.

you wouldn't be able to discern that without significant instrumented measurements. my tonneau soft tri-fold cover is less than 20 pounds, so let's call it a non-factor. technically, you're right that weight matters, but in this case, it matters very little.

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[smoncrief]

A few years ago I was driving a 93' s10 to work, 30 miles one way. Mix of curvey secondary and interstate (OH/WV) roads. Drove this for about 10 years so had plenty of time to experiment with and w/o a tonneau cover. Tailgate down, virtualy no mpg improvment. About 1 to 2 mpg increase with tonneau. Good to see the science behind it. 2023 Maverick XLT/EB/AWD/ Black with BAP/SIBL/tow package and hard tri-fold tonneau (from ebay)

 

[cyberdog]

TFL-Trucks did a test doing a highway jaunt, topping off using the same procedure before & after, then repeating with the cover installed. On their full size it resulted in a gain of of around 5-6% if memory serves. Doesn't sound like much, BUT at 40 mpg, that's a 2 mpg increase!

Not scientific, as my truck was still 'breaking-in' with maybe 500 miles on it when I installed the retractable cover, however, my highway mileage definitely went up. I was a 45-47 mpg and she'll do 50 mpg in ECO mode on 55-65 mph drives, with some 50 mph country roads thrown in the mix. - We drove to Lancaster for a weekend getaway in June, and the trip averaged 50 mpg over the course of that 180 mile round trip, including some undulating hills.

 

[K5Blazer]

Don’t forget, if you want to increase drag, and decrease mpg, be sure to install a bug deflector on your hood and add some side window deflectors. This works well even on hybrids.

 

[Sventinker]

Mythbusters answered the tailgate question years ago.

I believe the tonneau mpg improvement is negligible, at least from the articles I've read.

And in my experience with my Mav my fuel economy went down when I added my cover and bed mat. The weight is my suspected culprit.

 

[Automate]

you wouldn't be able to discern that without significant instrumented measurements. my tonneau soft tri-fold cover is less than 20 pounds, so let's call it a non-factor. technically, you're right that weight matters, but in this case, it matters very little.

Talk to an automotive engineer about how much effort they spend in reducing a vehicle weight by 20 lbs. You would be surprised.

 

[colinl]

Talk to an automotive engineer about how much effort they spend in reducing a vehicle weight by 20 lbs. You would be surprised.

that's an unusual attempt at a rebuttal, referring to a phantom expert testimony when it isn't even applicable.

I am confident that 20 pounds is irrelevant in the real world unless the 20 pound object is large enough to disrupt airflow, which is definitely possible, but isn't within what we were discussing. We are talking about a tonneau cover that improves airflow and likely weighs 15-30 pounds.

on any given trip, wind, traffic and many more things will make more impact than 20 pounds and you won't be able to measure the effect of 20 pounds, in effect, it is zero.

 

[Automate]

that's an unusual attempt at a rebuttal, referring to a phantom expert testimony when it isn't even applicable.

Ford spent millions of dollars in engineering and new factory equipment to make F-150 bodies out of aluminum instead of steel to save 400 lbs. Even after this, it costs them $500 extra per vehicle to make them out of aluminum. https://www.cars.com/articles/fords-switch-to-aluminum-f-150-increases-costs-500-a-truck-453589/

How much weight do you think the aluminum hood on the Maverick saves in weight?

In stop-n-go driving at low speeds the aerodynamic drag means almost nothing. Its all about the weight.

 

[colinl]

Ford spent millions of dollars in engineering and new factory equipment to make F-150 bodies out of aluminum instead of steel to save 400 lbs. Even after this, it costs them $500 extra per vehicle to make them out of aluminum. https://www.cars.com/articles/fords-switch-to-aluminum-f-150-increases-costs-500-a-truck-453589/

How much weight do you think the aluminum hood on the Maverick saves in weight?

In stop-n-go driving at low speeds the aerodynamic drag means almost nothing. Its all about the weight.

dude. 400 pounds is 20x more than the 20 pounds that you won't drop. I have no idea why you are doing this, but it's silly.

 

[RichardCranium]

This assumes all driving is at highway speeds. The aerodynamic drag will not be the same at all speeds and increases with the square of the speed. In fact there may be some mileage decrease a very slow stop-n-go driving due to the added weight of the tonneau cover and the minimal aerodynamic drag at these speeds.

Correct, I was basing my calculations on the assumption that people were saying that it was an average MPG increase and not per long distance trip. If the MPG increase is just for long highway trips, then the money savings will only be based on the miles they drive at highway speeds.
Thank you for the correction.

 

[RichardCranium]

Talk to an automotive engineer about how much effort they spend in reducing a vehicle weight by 20 lbs. You would be surprised.

my Chevy Cruze Eco does not have a spare tire because of the weight. So you are correct about Engineers wanting to do as much weight reduction.
Aerodynamics is also another thing that is very important to engineers as well. My same Chevy Cruze has grill shutters that close to maek the vehicle more streamlined.
The Eco version of the Toyota prius has no spare tire (Weight) and no rear window wiper (aerodynamics)
For this reason, I think that both items are important for an increase in fuel economy.
Ever hear of Newton's laws? Objects in Motion stay in motion, unless an outside force is applied (Drag). Another Law, F=MxA means that the amount of force required (horsepower) is determined by the mass of the vehicle times the acceleration. Therefore, a lighter vehicle needs less power to accelerate, and less resistance to slow down.
Weight adds another factor into the mix, and that is friction. By adding weight, you increase the coefficient of friction and therefore have more than just the drag affecting the MPG. FORD Engineers take all this into account to achieve the best efficiency which is why they spend as much as they do to design these trucks.
Now, that being said, I like numbers and it is fun to run the numbers. That is why I did my little calculation for the break even point. IF, and that is a big IF, you are achieving 2MPG increase with a tonneu cover in your driving situation, then great, buy one! If you drive a lot on the highway, it will probably pay for itself and help you reduce the use of evil gasoline (that is for the people that think that the only reason I post numbers is for money).

 

[MakinDoForNow]

Ever wonder why there is no square corner on back edge of cabin roof and the flat bevel edge points to about 6" above the top of tailgate?

 

[raymaines]

Sources for this? Seems quite high.

Let me offer this. The plastic on the top of my tailgate seems overly wide but that's apparently good for the MPG. Any sort of tailgate spoiler might increase MPG but would look weird (according to me anyway) and I don't really care about that absolute last half MPG, and I have a tonneau cover that makes up for the lack of a tailgate spoiler.

 

[jewc75]

my Chevy Cruze Eco does not have a spare tire because of the weight. So you are correct about Engineers wanting to do as much weight reduction.
Aerodynamics is also another thing that is very important to engineers as well. My same Chevy Cruze has grill shutters that close to maek the vehicle more streamlined.
The Eco version of the Toyota prius has no spare tire (Weight) and no rear window wiper (aerodynamics)
For this reason, I think that both items are important for an increase in fuel economy.
Ever hear of Newton's laws? Objects in Motion stay in motion, unless an outside force is applied (Drag). Another Law, F=MxA means that the amount of force required (horsepower) is determined by the mass of the vehicle times the acceleration. Therefore, a lighter vehicle needs less power to accelerate, and less resistance to slow down.
Weight adds another factor into the mix, and that is friction. By adding weight, you increase the coefficient of friction and therefore have more than just the drag affecting the MPG. FORD Engineers take all this into account to achieve the best efficiency which is why they spend as much as they do to design these trucks.
Now, that being said, I like numbers and it is fun to run the numbers. That is why I did my little calculation for the break even point. IF, and that is a big IF, you are achieving 2MPG increase with a tonneu cover in your driving situation, then great, buy one! If you drive a lot on the highway, it will probably pay for itself and help you reduce the use of evil gasoline (that is for the people that think that the only reason I post numbers is for money).

Most new cars do not have spares, they have inflation kits. My mustang came with fords fix a flat. I put a spare in it anyway. Its all about meeting CAFE standards. I dont care about their standards.

 

[raymaines]

[

very true. For the most part

Hood length
Cab height/length
Drop distance from top of cab to bed/tonneau cover
Bed length
Tail gate up/down

all combination for mpg negligible with a Mav

But with all this said I wouldn’t drive a pickup with the tailgate down unless cargo dictates.
Your mileage may vary.

Well, honest to F*****g God. If you're totally into MPG you wouldn't be driving a pick-up.

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