As a car owner, you’re probably well aware of how expensive it can be to own a car. Maintenance, insurance, and gas costs can all add up, so it’s no wonder people are looking for ways to cut back their expenses. With the average person spending around $150 to $200 on gas each month, people have begun to question if sticking to slower speeds could be the answer to saving money on gas.
Well, it depends on how you define “slower.” If you’re driving slower than 60 mph, then yes, your engine will most likely burn less fuel. There’s greater drag or wind resistance when you drive at fast speeds. To keep moving forward, your engine has to burn more fuel to push against the air.
However, if you’re driving slower than the speed limit, then the answer is no. Driving too slowly can be counterproductive because when your vehicle’s RPM level is below the low limit, your transmission will automatically shift to a lower gear. This allows the engine to turn faster under the same power.
Of course, speed isn’t the only thing that affects your vehicle’s fuel consumption. There are still other factors to consider.
Trivia: One Ford TSB released in the 1990s about fuel economy issues stated that a vehicle has 40% more wind drag at 65 mph than at 55 mph, which is one reason that, after the gas crunch of the early 1970s, nationwide speed limits were reduced to 55 mph from 1974 to 1995, when the national 55 mph speed limit rule was lifted. The “Turn Right On Red After Full Stop” at many intersections was instituted for the same reason to prevent extended idle time.
Heavier vehicles have greater inertia and rolling resistance, which means they need more energy to move. Smaller vehicles can also burn more fuel if they’re filled with several passengers and heavy cargo.
Some tires have more rolling resistance than others, and underinflated tires or misaligned wheels can also affect fuel mileage. Smaller tires than the OEM will reduce fuel economy, but tires that are overly large and heavy can affect fuel consumption too.
Roof racks, oversized mirrors, brush guards, and anything else that adds wind resistance will cause the drivetrain to work harder while pushing the extra air.
The shape and surface area of your vehicle’s frontal part can also affect fuel consumption. Aerodynamic cars with smooth lines tend to burn less fuel compared to boxy cars with sharp edges.
The faster you drive your car, the harder your engine has to work to overcome wind resistance. This means your engine burns more fuel than necessary. At 60 mph, your engine burns up to 15% more fuel. If you speed up to 70 mph, you’ll burn 25% more fuel.
The most fuel-efficient speed is different for each vehicle, but in general, maintaining a constant speed between 30 and 50 mph is the best for most vehicles. If you drive any slower, your engine will drop to a lower gear and use more fuel. Likewise, going faster than 60 mph also burns more gas.
Driving at a certain speed isn’t the only way you can reduce gasoline costs. Here are other tips on how to save gas:
Hauling bulky cargo on a roof rack increases wind resistance, which can significantly lower fuel economy. Instead, consider switching to a cargo box mounted on the rear instead. For example, a large rooftop cargo box can reduce fuel economy anywhere from 6% to 17% on the highway. In contrast, hitch-mounted cargo boxes only reduce fuel economy by around 1% to 5%.
As much as possible, avoid carrying heavy items in your vehicle. For every 100 pounds you carry in your vehicle, you reduce your fuel economy by around 1%. Get rid of any clutter, and keep only the essentials with you.
Just because your car isn’t moving doesn’t mean you aren’t burning fuel. While idling for a few minutes should be fine, idling for too long can greatly reduce your fuel economy. Idling can burn a quarter to half a gallon of fuel per hour, but this can still vary depending on the size of your engine and air conditioner (A/C). Instead of idling, park at a safe location where you can turn off your engine as you wait.
As much as possible, avoid slamming the brakes. Slamming the brakes means you’ll have to accelerate again, which consumes more fuel than necessary. Conserve fuel and keep yourself safe by observing the correct braking distance.
Nobody’s saying you can’t speed up when necessary, but accelerating too aggressively is bad for you and your fuel economy. Not only is it dangerous, it also causes your engine to burn more gas. Every time you step on the pedal, the accelerator pump funnels more fuel into the engine. If you can, drop a gear to pick up speed instead of hitting the gas pedal. Aggressive driving will consume a lot more fuel, even if you only do it part of the time.
Take advantage of your vehicle’s cruise control feature. It’ll help you maintain a constant speed, allowing your engine to go through less RPM and burn less fuel if you’re not on hilly roads that will cause the transmission to downshift a lot.
Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.