Tonneau Covers and Fuel mileage

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McBroom

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Do tonneau covers really improve your fuel efficiency??
Not interested in what the brochure says!!
I'm wanting to know real world experience.
Do tonneau covers really help with fuel mileage??

Blue Mule
 

BOWERSFJ

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I believe Myth Busters, or Motor Trend, did a pretty extensive test on this one ... If I remember correct, it wasn’t a huge diff either way ... Bottom line is really the issues of cargo security and element protection, and convenience of access ... In other words, do you wanna protect your ****, do you wanna lock up your ****, and would a cover get in the way of puttin your **** in there ...


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S1kRR.Cid

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Had one in the GMC . And not. Noticeable difference if u ask me . Especially if u get the fiber glass one the extra weight .
 

BOWERSFJ

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Had one in the GMC . And not. Noticeable difference if u ask me . Especially if u get the fiber glass one the extra weight .

So you think the fiberglass cover COST you mileage ?


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McBroom

McBroom

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I've got a trip fold on the Blye Mule now and can't tell a difference yet. It's the first one I've ever had. I do like that when I lock the truck it locks the cover.

Blue Mule
 

S1kRR.Cid

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So you think the fiberglass cover COST you mileage ?


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Can't say 100% but I was able to tell difference on 1500 .. but if u want stuff covered that shud be the priority to buying on not the milage IMO
 

16Ram4x4

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They claim over time that a tonneau cover will save you money and boost your fuel economy. I have a Extang Trifecta Emax and I like it for the weather protection and security to what I may be hauling. Plus it keeps the inept idiots from using your pickup bed as there personal trash can on the way by
 

MarineBSP

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Limited data on my truck before/after tonneau cover suggested I gained about 0.5 mpg adding it. BUT I expect every truck differs a little, AND I soon added wheel-to-wheel side steps to a truck that started with molded mudflaps - so the sidesteps might have smoothed mud flap turbulence, or the truck might have just been breaking in (all this under 3K miles).

I recall reading back-to-back testing that indicated the open bed with a tailgate has less drag than lowering or deleting the tailgate, at highway speeds. The 'air bubble' trapped by the tailgate makes the truck behave more like some of the Kamm tail designs on cars and reduces drag.

Personally, I have a tonneau entirely for protecting cargo from weather, theft, and blowing out of the bed. I am interested in mileage, but practicality wins, or I wouldn't have a truck =).
 

BWL

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Great for securing and keeping stuff dry, but no fuel economy gain. No loss either though.
 

JayLeonard

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I have one now and had one on my ex for 10 years. I like the soft tri-folds as they are easy to remove/install as needed.
I know whenever I had the cover off I was hauling something, so I couldn't even think about comparing mileage.
 

1stindoor

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Since we're on the topic...I've been looking at them lately. I've had open bed trucks since 1980, and I like the rails I have on the bed. But I'm starting to look at the "high-dollar" metal rolling type that lock. Since I have a 2500 I'm not expecting any fuel savings, but if anyone has any experience with that type of cover I would appreciate your thoughts.
 

RamInfo

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When I had my Dakota I read a wind tunnel evaluation that had been done, focusing on reducing drag and, by extension, increasing mileage on that truck. IIRC, the rankings were:

1. Truck with topper shell (most drag)
2. Bare bed, tailgate closed
3. Bare bed, tailgate open (very little difference with #2)
4. Tonneau cover (least drag)

When those runs were completed, they put a stock open-bed truck back into the tunnel but with mirrors removed. Removing the mirrors had more effect on drag than any change on the bed except for adding a topper shell, which still had the highest drag.

I run a tonneau cover but mainly for convenience in hauling and hiding stuff, and to keep the bed and contents dry.

Best,
DG
 

crazykid1994

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I noticed about .25-.5 mpg gain when I had put my tonneau cover on. Lost that plus some when I switched to my all terrains. Now I’m down to around 15.5 mpg with this weather plus other stuff I’ve done to the truck. Picked some mpg back up with the efan swap but I’ve lost most of that with my heavy foot now that the truck feels more responsive
 

indept

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I saw no noticeable change in mpg after putting mine on. I have read articles that claim they have aerodynamics such that the air flows over the cab and over the tailgate and never enters the bed. So that would explain those of us that see no difference.

That still won't prevent the dealer service from claiming that your tonneau was the reason your transmission failed prematurely and voided your warranty though...:rolleyes:
 

Jessica Smith

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They claim over time that a tonneau cover will save you money and boost your fuel economy. I have a Extang Trifecta Emax and I like it for the weather protection and security to what I may be hauling. Plus it keeps the inept idiots from using your pickup bed as there personal trash can on the way by
The opposite is more likely.

The primary reason that trucks these days are going on diets with aluminum body panels and the like is because a lot of fuel is used in stop and go, and more weight = more work = more fuel.

On the highway, there are many tests that show that tailgate up or down makes no difference, as it becomes a rather static low pressure area anyway with a bubble of rather still air, which makes sense as I see people toss garbage in their bed and more often than not it can stay in there for weeks without being blown out.

So if tailgate doesn't matter, than tonneau isn't likely doing anything aerodynamically either.

Really practical though IMO, keeps stuff dry and safe.
 

avantiguy

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Realistically, if there was a measurable difference all pickup trucks would come from the factory with a tonneau cover. The manufactures are spending really big money to gain any improvement in fuel economy and they could probably add a tonneau for $50/truck and just add it to the price.
 
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