Many truck owners have been told that adding a tonneau cover to their truck can save on gas. But is it true or just a rumor? The Mythbusters show took a crack at this question, but it’s still a topic of debate. To really figure out if a tonneau cover can help reduce fuel consumption, it helps to understand what they do and how they impact a truck’s aerodynamics.
Can a Tonneau Cover Improve Gas Mileage?
A tonneau cover covers your truck bed, smoothing out the airflow over it. In theory, this helps to reduce drag, which can improve gas mileage, especially at higher speeds. The Mythbusters crew actually ran tests to see if covering a truck bed made any difference to fuel efficiency. They found some impact, but it wasn’t huge. The results showed that, yes, a cover can help, but how much it helps depends on different factors.
Different Types of Tonneau Covers and Their Impact on Fuel Economy
Not all tonneau covers work the same way. The type of cover you choose can play a role in whether you actually see any gas savings.
Hard Folding Tonneau Covers
These covers are made from durable materials like aluminum or fiberglass and are designed to fold up. They’re heavier than soft covers, but they also create a flatter surface, which can help with aerodynamics. For long trips or highway driving, hard folding covers can offer some fuel savings because they cut down the air resistance.
Still, the extra weight from these covers can eat into any gas savings. In some cases, people see better gas mileage, while in others, the difference is too small to notice.
Soft Roll-Up Tonneau Covers
Soft covers, often made from vinyl or other lightweight materials, are cheaper and easier to install. These don’t offer as much resistance to the wind as hard covers do, which makes them less effective in improving fuel efficiency. They’re more useful for keeping cargo safe and dry than for saving on gas.
Retractable Tonneau Covers
Retractable covers slide back into a storage canister when not in use, giving flexibility. These covers, usually made from metal slats or hard plastic, provide a smooth, flush finish over the bed. This kind of cover can help with gas mileage a little more effectively than soft roll-ups because of how snugly they fit.
Retractable covers are pricier, though, so unless you’re really focused on fuel economy, you might not save enough gas to offset the cost of the cover.
One-Piece Hinged Tonneau Covers
These covers lift up as one big piece and are usually made from heavy-duty materials like fiberglass. One-piece covers provide the best aerodynamic advantage by forming a solid, flat surface, which minimizes drag significantly. They’re probably the best choice if you’re specifically aiming to improve gas mileage.
However, these covers are heavy and not cheap. Plus, you won’t be able to carry larger items in the bed without removing the cover first.
How Much Gas Mileage Can a Tonneau Cover Actually Save?
According to various sources, the fuel savings from a tonneau cover range anywhere from 5% to 10%. But that’s mostly under ideal conditions—like driving at steady, high speeds on highways. For most truck owners who do a lot of city driving or short trips, the improvement might not be as noticeable.
If you drive mostly on the highway, you could save around 1 to 2 miles per gallon with a tonneau cover. But if you’re driving in stop-and-go city traffic, the savings might barely register.
Factors That Impact How Much Gas You Can Save
Several things affect whether you’ll see any gas savings with a tonneau cover, from your driving habits to weather and your truck model.
Speed and Driving Style
Driving at high speeds creates more drag on your truck, and a tonneau cover helps reduce that drag. So, if you’re mostly doing highway driving, the cover may give you a fuel boost. In city traffic, though, where you’re stopping and starting all the time, the cover won’t have as big an impact.
Weight of the Cover
Adding a tonneau cover does add some weight to your truck. Heavier covers, like hard folding or one-piece covers, may counteract any potential fuel savings by making your truck slightly heavier.
Weather Conditions
When driving in windy conditions, a tonneau cover may actually help stabilize the truck and reduce wind resistance. But in calm weather, the difference is small. In rainy conditions, tonneau covers also help keep the cargo dry and prevent water from pooling in the bed, which could increase drag.
Type of Truck
Larger trucks, like full-size models, experience more drag than compact trucks, so the cover’s effect might be more noticeable on a larger truck. Smaller trucks may see less improvement simply because they already have lower drag.
Myth or Reality? Do Tonneau Covers Really Save Gas?
After examining various sources and studies, it seems that the idea of tonneau covers saving gas is partially true. If your goal is to improve fuel efficiency and you do a lot of highway driving, then a tonneau cover, especially a one-piece or hard folding cover, could help. However, don’t expect a tonneau cover to drastically cut your fuel costs, particularly if most of your driving is done in city traffic.
