Toneau covers help MPG???

I traded from a Dodge Ram and had an Under Cover put on my Ram after a couple of years. We all hear that they help MPG's. Not in my case. I averaged 15 mpg with the Ram before and people think I'm crazy but after I only average 14.5 mpg. What do you think? Improve, no difference or loss of mpg?

 

Myth Busters did a pretty in-depth study of this: They found that the best mpg's are to be had by tailgate up and nothing in/on the bed because the wind coming over the top of the cab and down into the bed creates a kind of "vacuum." I've tested it myself. Even driving the highway with the tailgate completely off the truck was much worse than just leaving the tailgate up.

 

I saw one where they did about the tailgate up/down, nothing about the toneau as far as I remember.

I kinda want to get a toneau, but dont want to hurt the mpg's since that is the reason for trading in the first place.

 

The Myth Buster did a fiberglass bed cover and not a canvas one. They said the fiberglass one showed no change in MPG's. But what about all the extra weight of the fiberglass? I had a canvas one on my silverado and it added about 3 MPG's.

 

When I had my truck I also had a tonneau. 18mpg mixed and 21/22 highway.

 

I have had a cover for over a year now and NO change... Highway, Interstate, short and long trips... Makes the truck look good though ;-)

 

since adding a cover, it increased my mpg only in the highway.

 

No change for me, but I didn't buy it for that. I bought it to keep my shit dry and "safer"? Outta sight, outta mind.

 

+1

btw it's a soft Extang cover so minimal weight gain. Also I had the same results (no mpg's gained or lost) with the same type of cover on my last truck, a Dakota.

 

^^ This, right behind the back window and front of bed the air kind of circles and that inturn pushes the air over the tailgate. So no drag with tailgate up or down. A cover will not change MPG's either way unless its heavy and then it can lower the MPG's.

 

0 mpg gain or loss for me. I've got a soft cover so there is hardly any extra weight added to the truck. I had this setup since I bought this truck 2 years ago and as I already said, no difference at all for me. Also mpg savings were not the reason I purchased mine for.

 

I have a hard cover on mine since about May and I haven't noticed a difference at all.

 

You can't make a blanket statement whether it helps, hurts or does nothing to MPG's since it depends on the vehicle 100%. Different vehicles, different shapes, different air flow characteristics. Even a long bed and a short bed model of the same truck would react differently to a tonneau. On my DCSB, I got a slight increase, an other trucks I've owned I've had it make absolutely no difference at all.

 

To get an appreciable drag reduction, you'd need a tonneau cover and a tapered tailcone piece that extends 5-6 feet behind the tailgate, like this:



Big rigs that spend most of their time on the highway have a device available that works in the same principle, but is restricted in length by regulation:

 

My mileage improved a little after the access cover was put on

 

No gain no loss, bought to keep my bed dry when sleeping outside and hauling stuff that needs to be dry.

 

I only started getting more than 20mpg after I installed my toneau cover.

 

No change. I was getting around 21mpg before Ethanol was added to gas. Now I get about 18mpg. Ethanol is the mpg killer. Toneau doesn't make a difference. Toneau is great when traveling & you have lots of stuff to carry.

 

They don't add MPG, but they are good for at least 10 horsepower!