Does Driving Slow Save Gas?
One of the most common questions about fuel efficiency and factors that contribute to reducing fuel economy (or how to best save fuel) is related to speed: Does driving slower actually save gas? Or is it just folklore?
Let’s take a closer look.
Does Driving Slower Save Fuel
Yes—sometimes—but also no.
The truth is that every automobile has a sweet spot at which the car’s gas mileage peaks; for most vehicles, that’s between 50 and 60 miles per hour, depending on other external conditions such as proper tire inflation, wind resistance, and more. Finding the optimal fuel economy doesn’t mean driving too slow, but nor does it mean you should drive fast.
Let’s look at the factors that contribute to driving costs if you’re looking to save money on gas and get optimal fuel efficiency:
- Drag efficiency: this includes wind resistance (which increases at higher speeds), rolling resistance (the friction of your tires on the road surface, which generally increases with larger and/or grippier tires and decrease with proper inflation), and even the shape of your vehicle (boxy SUVs, for instance, will have more drag than a sleek sportscar) and its weight (a heavily-loaded vehicle will have more drag).
- Engine efficiency: As a general rule, car engines are most efficient when in top gear but low revs; you can find that speed by checking the lowest speed at which your vehicle will constantly sit in its highest gear before it shifts down, ideally just below 1500 rpm (and in eco mode, if your car has one). For most vehicles, this is a highway speed of 50-60 miles per hour.
- Braking and accelerating: Hard braking and accelerating are far less efficient than gently transitioning; as a general rule, safe driving tips at the speed limit result in fuel savings. You shouldn’t be mashing on the gas pedal or brake if you want to stretch your gas stations fuel costs.
- Time spent idling or with a cold engine: Idling is great for reducing fuel economy, as is driving with a cold engine (so bundling errands rather than making lots of small trips can save money on gas).
Let’s look at what those principles mean in practice, starting with 7 fuel efficient driving techniques or driving tips that can help you get the best fuel costs.
7 Fuel Efficient Driving Techniques
Check out these driving tips that can help you save money on gas as a result of striving to provide optimal fuel efficiency:
- Brake and accelerate gently and smoothly. Mashing on the gas pedal or slamming on the brakes, while all too common in city driving and heavy traffic, are hard on your fuel economy and engine. Instead, work on letting up on the gas to more gently decrease speed, for instance.
- Understand your transmission’s optimal fuel efficiency. If you drive manual transmissions, take the time to educate yourself (perhaps with the help of the owners manual) as to the best way to shift efficiently.
- Spend time with your owners manual to ensure you understand which functions might inadvertently be reducing fuel economy. For example, if your vehicle has an eco mode or you drive hybrid vehicles, make sure you understand what affects fuel consumption. Different factors affect different vehicles differently; though driving slower actually save wind resistance for boxier vehicles, that will affect more streamlined vehicles less, for instance.
- Look into cylinder deactivation. Cylinder deactivation, run by on-board computer systems to limit unnecessary drains on your gas tank, works to essentially freeze valves that allow fuel and air into selected cylinders so that your engine uses fewer cylinders when it doesn’t need as much power, effectively making it a smaller engine so that you aren’t unnecessarily reducing fuel economy by using more engine than you need.
- Use apps like AAA’s TripTik Travel Planner to drive the most efficient routes. The TripTik Travel Planner can also help you identify gas stations along your route with the best gas price per gallon, as well as gas stations that offer premium fuel. Planning ahead of time in this way can help increase your fuel savings and help you save money on gas.
- Drive the speed limit and in the right lane when driving highway speed. Not only should this limit unnecessary acceleration and braking, but can save your engine unnecessary work. This doesn’t mean driving slow, but rather striving to provide the most efficient use of your engine when traveling at highway speed to limit driving costs; driving too slow is unsafe and can get you a ticket.
- Plan your trips ahead of time. In addition to using apps like TripTik Travel Planner, planning ahead of time can limit unnecessary trips. Your engine draws fuel from the gas tank when idling, warming up, running the air conditioner in hot weather, and so forth—not just in the act of driving. So instead of making lots of short trips, running a bunch of errands at once can actually contribute to lower fuel costs and limit unnecessary fuel consumption, thus helping you save money on gas.
Let’s look a little more at how proactive and safe driving can save fuel and help stretch your cars gas tank, limiting your fuel costs.
How Much Fuel Can You Save With Smooth Proactive Driving
The best part about trying to chase ways to save fuel costs is that most of the time it also means driving more safely. It is less about choosing to drive fast or driving slow and more about driving a safe highway speed and driving the speed limit. The best way to save money on gas and increase your cars gas mileage is by limiting actions that result in unnecessary fuel consumption. The same driving tips that you might see for a plug-in hybrid or hybrid vehicles can also help limit your driving costs; striving to provide a smooth, safe experience is generally going to save fuel costs!
But just how much can you save money on gas by embracing proactive driving tips?
Depending on where you look, it may be as much as 40% of your fuel costs. So let’s recap those principles:
- While it’s generally true that driving slower actually save wind resistance, it’s not necessarily true that driving slower actually save gas. Driving too slow can cost you by reducing fuel economy.
- More important is how you use the gas pedal and brake; even acceleration is important, but even more so, letting off the accelerator rather than braking is one of the top driving tips for those looking to save fuel. Practice coasting to a slower speed as able as long as you can still drive safely doing so.
- To get the best gas mileage and most efficient fuel consumption, drive at times when you’ll deal with less traffic; that may require more planning ahead of time, but being able to drive a more consistent highway speed improves fuel efficiency.
Those are the big principles for increased fuel efficiency. Of course, in many cases, looking at a vehicle that gets better gas mileage (such as hybrid vehicles) may be the best way to get optimal fuel efficiency.
Matthew is a freelance writer who is passionate about technology, music, photography, and decentralized finance.