Do Tonneau's actually improve MPG's?

I use a roll up tonneau cover. Moto fits in back when rolled up, otherwise my skis are covered when I stop at the bar. 25k miles with a 2016 MT, 22.5mpg overall. Probably mostly because no interstates and higher elevations.

 

I noticed an uptick in MPGs after I put a set of Bed Bars in my truck, I would assume they are disrupting the bubble of turbulence that would normally be back there.

 

No they dont,its been proven many times

 

I doubt it. With the the Toyota tonneau you probably lose MPG if anything. That thing is so heavy, weighs 60-70lbs probably.

 

I drive 65mph regularly. With coasting downhill and use of engine braking you can easily get 25mpg or more in the manual if you try. This is with a stock truck of course.

 

No difference in material. They are not interesting responses, the fact, as proven time again and readily available at multiple websites, is they make no difference. If anything the data point towards a slight decrease.
Stuff like this is not opinion. It's tested science and physics.

 

yeah Downhill takes a good load of the engine. I went downhill 30 miles at 45MPG once and I got 35MPG according to the dash meter.

 

https://www.consumerreports.org/cro/news/2013/08/pickup-truck-tailgates-and-fuel-economy/index.htm

 

Ford engineers don't agree. I'll take the word of scientists and engineers in private industry over a Journalist at Consumer Reports.

https://www.youtube.com/watch?v=oEkiDsVGr9c

 

Why does everybody keep posting links to consumer reports. This is the same magazine that said the Tacoma is shit and ranked it at the bottom of the class . Yet we all bought one. So why are we listening to them on this topic

 

Nope. But my undercover allows me to keep things locked back there

 

I have a much younger friend who drives like you. I almost grandma, only the sliders holding me back. My younger friends rolls his eyes when I explain that I'm saving my truck. Tells me to use the thing!
Duane

 

This has been scientifically tested.


No.

Caps and covers decrease gas mileage from weight and decreased aerodynamics.

 

I have a Lund Genesis Elite, trifold, soft cover. I am very happy with it.

No change in mpg with install. I calculate every fill-up. Avg. 23/24 mpg, with 27 mpg on extended interstate trips. 2017 SR, MT, AC, 4 banger with approximately 14,000 miles.

 

I didn’t read beyond this post but I’ll add to the above quote:

The red “bubble” is a high pressure zone which effectively becomes part of the truck as far as the wind is concerned, thus making the truck more aerodynamic.

The blue line is air getting sucked down and against the back of the cab by a low pressure zone which exists in the absence of a tailgate or possibly after a tonneau has been installed. This creates a lot of drag against the back of the cab.

 

My tri-fold soft tonneau is like a parachute. It's a bit old so the material is loose and catches the wind. I fold it to the cab for highway driving.

My fiberglass canopy is cab height, has no racks and sits tight up to the cab. Can still feel the extra weight and surface area. I only put it on the truck when I need it, no point in lugging it around all the time.