Tonneau Covers and MPG

[Ventilator]

Has anyone noticed any significant increase in MPG after installing a Tonneau Cover on their truck? Lots of conflicting information when searching for proof, so I thought I would ask the guys with the 2014's here.

 

Conventional wisdom says that there has to be air flowing into the open bed and hitting the tailgate, thus decreasing it's efficiency? It does allow at least some air to flow around it between the tailgate sides and the body sides, but no real flow of air.

 

Have never had a Tonneau Cover on a truck, just toppers.

 

If you feel you have any increase in MPG with your cover, can you please let me know what brand and what the increase is, if any?

 

If this is just a myth, or illogical thinking on my part, please let me know that as well. Let me have it!

[dodgehemi0]

There is very little impact on these new trucks. I had one and I did not notice an increase. It is nice however to have a very large trunk for long trips.

 

 

Sent from my iPhone using Tapatalk -

[CAtaylor]

There is very little impact on these new trucks. I had one and I did not notice an increase. It is nice however to have a very large trunk for long trips.

 

 

Sent from my iPhone using Tapatalk -

This^^. I have the Diamond Back and got nothing from it but a good trunk and a bed cover I can haul stuff on.

[TJay74]

Nothing significant at all, I've had my Extang on my 2010 and then put it on my 2014 and noticed nothing at all.

[Ventilator]

Thanks guys! Of course the Manufacturers disagree with you all, but they sell covers for a living.

[gilles81]

The way the trucks are made now the wind creates a boil in the bed and then new air coming over the cab hits the boil of air and flows over the bed....so I would say no increase... now on a 15 year old truck... I did notice a mpg more on my 97 Silverado on the hwy but still not a reason to buy one.

[bills]

I installed an Xtang roll up on my new Sierra and saw no difference at all, but I do have a really big trunk now as others have stated. Was it a good move - YEP!

[14'SilveradoLT]

GM posted in an article a while back that a cover would "decrease" drag and a soft cover that "conforms" to the air, even more so.

 

I'd imagine you might go from 22.1 to 22.2 on hwy and 15 to 14.99 in the city (due to added weight, lol).

[Imcrazy]

no diff here

[j13smiley]

The way the trucks are made now the wind creates a boil in the bed and then new air coming over the cab hits the boil of air and flows over the bed....so I would say no increase... now on a 15 year old truck... I did notice a mpg more on my 97 Silverado on the hwy but still not a reason to buy one.

This...

 

Covers add nothing... Neither does leaving the tailgate open.

[Mike1220]

I'm surprised y'all aren't seeing much difference. I drove my truck home from dealer when I got it, 2 hours, 140 miles. Averaged 16 MPG at between 70-75 MPH. Truck was already leveled with magnaflow catback and AFE air intake. I drove it back about a month later for an event that I had near the dealer, and on the way there and back, I was going, once again, between 70-75. And I averaged between 20-22 MPG. That's on a CCSB Sierra SLT. By the time that I went back I had time to purchase and install my BAK Roll-X tonneau. It helped my mileage a lot!

 

Other myths like leaving the tailgate open are just BS, leaving the tailgate open, or even removing it all together (which is surprisingly the worst thing to do) disrupt the airflow over the truck that flows down to the bed, causing far more drag becuase the air flow can not become uniform like it can with the tailgate up. The tailgate up keeps the air flowing in a circular movement which basically repels some of the air that comes over the cab. Therefore keeping the drag less.

 

 

 

Sent from my iPhone using Tapatalk

[gilles81]

I honestly don't think you gained 6 mpg from a cover maybe your 16 mpg had a lot of idle an city miles on it and hit reset for your trip back when you got on the hwy. hell 22 mpg is hard to get

[Mike1220]

I honestly don't think you gained 6 mpg from a cover maybe your 16 mpg had a lot of idle an city miles on it and hit reset for your trip back when you got on the hwy. hell 22 mpg is hard to get

It's only on highway that I gained so much. And 16 was from the dealer to home. I reset it when I got on the highway. But it may have been different if the truck had a bit of time to be broken in first. Keep in mind when I left the dealer it only had about 21 miles on it

 

 

Sent from my iPhone using Tapatalk

[gilles81]

You got it from a dealer with 21 miles on it and a leveling kit magnaflow exhaust and a cold air intake .... What dealer does that

[Mike1220]

You got it from a dealer with 21 miles on it and a leveling kit magnaflow exhaust and a cold air intake .... What dealer does that

Not cold air intake. Just a modified intake with less restriction. And the dealer is Courtesy Buick GMC in Lafayette LA. They are a HUGE dealer! They had around 120 2014s Sierras alone sitting on the lot!! Some slightly modified and others bone stock. All the way from the lowest WT to a fully decked out denali. They have their main location + a huge warehouse down the street about a mile that houses abunch of other cars for them. They sell abunch of stuff. I saw their shop when I picked up my truck and met the shop foreman that worked on mine. I got lost just looking at the damn shop! It had to of had atleast 50-75 bays for working on vehicles, and that's no exaggeration my friend. Also the staff over there was very kind and enjoyable to work with.

 

Btw, I have no affiliation with the dealer other than the fact that I purchased my truck there and get it serviced there as well when I'm in the area, I just had a great experience there and enjoy sharing with others.

 

 

Sent from my iPhone using Tapatalk