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Are you strapped for cash and looking for ways to save money? A quick way to start saving money now is cutting down on your vehicle’s fuel consumption. One common question related to saving on gas (and money) is, “Does driving slower save gas?”. Let’s talk about how the speed at which you drive effects your gas mileage and a few other tips for improving your vehicle’s fuel economy.
Table of Contents
Why Driving Faster Increases Fuel Consumption
All things being equal, driving faster is worse on your fuel economy because of the drag created on your vehicle.
Drag is the resistance force created by air (in the case of vehicles) on your vehicle as you drive.
The faster you drive and the more force (speed x mass) you create, the greater the resistance force (force acting in the opposite direction).
How Driving Too Slowly Can Also Increase Fuel Consumption
This depends on your engine, but if you drive too slowly, you can potentially be running your engine inefficiently.
As a general rule of thumb, the best operating range for fuel efficiency is in the 50 – 60 mile per hour range, but if you must drive slower, try to drive in the low rpm range of whatever gear you need to be in to maintain your speed.
Being higher in a gear typically uses more rpms. The more rpms, the more potential for fuel consumption. Also, higher rpms are correlated with friction losses as well (although minor in nature).
Why Consistency is More Important for Fuel Consumption
A factor in fuel consumption that is more important than how fast you drive is how consistently you drive.
As most of us know, you get better fuel economy on the highway than in the city. Why is this? It’s primarily due to the stop and go traffic generated in the city by traffic, stop signs, traffic lights, pedestrians, etc.
Each time you stop, you lose all of your momentum. When you start to accelerate to get back to the speed limit, you are now starting from scratch. This means you have massive friction forces (friction between tires and pavement) to overcome to start rolling.
When you drive at a consistent speed for long stretches, the only fuel needed is to maintain that speed. In other words, you only need enough fuel to overcome the drag forces caused by air and friction forces caused by the pavement at that speed (friction should be minimal compared to starting from a stopped position).
Other Quick Tips for Great Fuel Economy
Avoid Tailgating
For many reasons, tailgating is a terrible a driving habit. First and foremost, it leads to more accidents, road rage incidents, and can even lead to a ticket. From a fuel consumption standpoint, tailgating leads to more frequent use of the brakes and less consistent driving. This all adds up to wasted fuel and less cash in your pocket. Don’t tailgate.
Try to Coast to a Stop at Lights and Even Practice Signal Timing
If you do a lot of driving in the city, practice the art of coasting to a stop at traffic signals.
Safety is of the utmost importance, but if you can coast to a stop and possibly time the light, you’ll save on fuel consumption and get much better mpg in the long run.
Accelerate Quickly
When accelerating, try to accelerate quickly to get to the ideal speed. The longer your engine needs to accelerate to achieve the desired speed, the more fuel your vehicle consumes.
Cruise Control is Your Friend on Long, Flat Highway
Cruise control helps you get great gas mileage over long, flat stretches of highway, especially if you’re able to stay in the 50 – 60 mph range. People, in general, are more likely to allow the speed to fluctuate more, which requires more acceleration (and more fuel consumption).
Abandon the Cruise Control on Steep Inclines
Unfortunately, cruise control is not as effective at navigating mountains or other steep inclines. Again, safety is highest priority, but to save the most fuel, you should try to drive slower when going up an incline and lay off the brakes as much as possible when going down a decline.
Conclusion
Driving slower doesn’t necessarily correlate with better fuel economy. Driving faster does lead to more drag forces acting on your vehicle, but there are so many other factors that contribute to your gas mileage.
More important than how fast you drive is how consistently you drive. As a general rule of thumb, if you consistently drive the speed limit and follow the handful of tips above, you’ll greatly decrease you fuel consumption and save money on gas for your vehicle.
If you’re interested in learning more, please read how to save money on gas for your car.
Do you practice any of these tips for saving on gas while driving? What do you do to get better fuel economy?