*This post may contain affiliate links. As an Amazon Associate we earn from qualifying purchases.
Trucks are not known for having the best gas mileage.
Virtually all of them have poor gas mileage, but are capable of powerful pulling and weight carrying capacity. However, due to their low mileage, everyone tries to find ways to increase their gas mileage.
One of the popular things that people consider is trying truck bed covers or toppers to make the truck more aerodynamic, thereby reducing drag and increasing mileage but will that work?
Do truck toppers or bed covers actually help increase the fuel mileage?
Truck toppers or truck bed covers will increase your fuel mileage on average but only by a tiny percent (1-2%). So buying a topper or truck bed cover is not worth doing unless you need it for another reason.
Having slightly better gas mileage is a nice perk but doesn’t make buying either a topper or cover worthwhile just for the slight increase in fuel mileage.
If you need a topper or bed cover to give you much more storage room in your truck then awesome, but buying one just for slightly better MPG will cost you more than it saves.
In the rest of this article, I will go a little bit deeper into this subject about truck bed covers/toppers and even cover the Mythbusters!
To see the most popular truck accessories currently on the market just click here.
Why Does A Truck Bed Cover Save You Gas?
Trucks are not the most aerodynamic vehicle and when a truck is moving at a high speed, the air comes from the front and after crossing the middle of the truck, it plunges down.
Now if there was no tailgate or truck bed, the air would simply be gone after flowing over the truck cab, but the tailgate and bed creates some resistance, which translates into drag.
To compensate for the drag, the trucks burn more fuel than usual leading to lower fuel mileage. The truck bed also creates an air pocket that increases the drag thereby lessening the mileage.
The obvious solution to this problem would be to simply put down the tailgate, but in reality, this actually creates more pressure on the bed, thereby increasing turbulence and decreasing fuel mileage even more.
A truck bed cover saves fuel because it helps to decrease the drag on your truck by keeping the air flowing better after it passes over the cab.
One of the only solutions that actually works to decrease the drag and increase the fuel mileage of a truck is a truck bed cover/topper.
How Much Better Gas Mileage Do You Get With A Truck Bed Cover?
A lot of scientific experiments were done to prove what kind of gas savings a truck bed cover can result in. A recent experiment used 4 trucks for a full sized wind tunnel study, with and without truck bed covers.
The wind tunnel study found that using bed covers or Tonneau covers decreased the drag on the truck. The difference was not very big, but could be measured.
On average the drag of a truck decreased by 5.7% when a bed cover was used thereby increasing the gas mileage by 1.8%. So if the truck was getting 20mpg with a truck bed cover it got 20.36mpg.
Although a 1.8% increase in gas mileage seems negligible, it does add up over time.
However there have been other studies done as well, which concluded that there is no noticeable mileage increase due to installation of a truck bed cover.
Hence , as far as we understand, it was proven that there is some aerodynamic benefit due to truck bed toppers, but the amount of the increase in gas mileage was never really proven objectively in a real world road condition as the first study was conducted in a wind tunnel not on the road.
Does The Gas Mileage Depend On The Type Of Truck Bed Cover?
As we have established, having a truck bed cover has a slightly positive impact on the gas mileage of your truck. However, you should always opt for a truck bed cover, not only for their mileage benefits, but also for a number of other benefits, which we will discuss later in this article.
Now what type of truck bed cover you choose to get has a direct effect on the gas mileage of your truck.
If you go with a vinyl bed cover, it is easy to install and can also be uninstalled and packed away easily if needed. However, this will only give you a slightly better mileage than no cover.
If you go for the hard fiberglass bed cover, its weight could even nullify the increased gas mileage you get from covering the truck bed.
All truck bed covers will save you about the same amount of gas. In general you are better off getting a bed cover with the best reviews that fits all of your other needs the best.
If you need something that can easily be installed or removed then go with a vinyl bed cover. If you constantly find yourself needing a workspace then getting a hard truck bed cover that you can write or work on is likely best for you.
Mythbusters Study On Truck Bed Covers
In one episode of Mythbusters, the effect of tonneau covers or truck bed covers on mileage was studied. They experimented with 4 different scenarios: tailgate down, mesh tailgate, no tailgate and hard Tonneau cover.
With this experiment it was found that only a mesh tailgate increased the fuel mileage of the truck and nothing else worked. The mesh tailgate helped in passing through the wind without creating any pressure difference and reduced the drag significantly.
So, this proved to be the most successful modification among all truck bed and tailgate alterations at increasing gas mileage.
However, Mythbusters was criticized for using only one truck with critics suggesting that different types of truck can yield different results in real world road and weather conditions.
They also only tested one specific style of cover and not all of them so some could prove better than the specific one that they tested.
Do Tonneau Covers Keep Water Out?
People buy Tonneau truck bed covers not only to increase mileage but for various other purposes as well. One of the major reasons people buy this bed cover is for keeping water out of the truck bed.
The truck bed may have your belongings or tools in it and you would want to keep water off of them.
The truck bed covers prove beneficial in this regard. They are mostly able to keep water and rain water out of the truck bed area so it keeps the things inside nice and dry.
While a hard fiberglass cover can keep the water out more efficiently, the weight that is added due to the fiberglass material decreases the truck’s gas mileage.
What Truck Bed Cover Doesn’t Leak?
If your purpose of a truck bed cover is to protect your belongings kept in the bed, you need to choose a bed cover which gives you maximum protection from the weather conditions.
Hard bed covers give you the best protection from rain, snow, and ice. They not only repel water, but also block out and help drain any excess water. Vinyl covers are very popular, but they are water resistant and not really waterproof.
The hard bed covers are made of fiberglass material and they are the best option for you to avoid any chance of a leakage.
Is A Truck Bed Cover Worth It?
A truck bed cover is always worth the investment if you are trying to do more than just save on fuel costs.
Truck bed covers not only protect your belongings from the harsh weather conditions, but a hard bed cover also protects your valuables from thieves.
If the road is full of dust and debris, the bed cover helps you keep your truck bed clean and even slightly improves your gas mileage.
Buying a truck bed cover is worth it if you ever haul tools or equipment in your truck bed or if you find yourself needing a flat workspace often.
Truck bed covers are not very expensive, and installing them will greatly improve your truck’s looks, prevent any rusting on the bed and could even help you get a better resale value since your truck is in better shape.
As the benefits outweigh the cons by far, for most people a truck bed cover is worth buying .