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What Is the Best Driving Speed To Save on Fuel and Still Have Some Fun?

Before dismissing this article as being another one of those “drive as slowly as possible to save a few bucks” pieces of advice, note that we believe you can save money while also maintaining a good driving pace. It only takes a while to find the sweet spot in driving speed that can offer both enjoyment behind the wheel and economy at the pump.
Every vehicle has a specific economical speed 7 photos
Photo: Image by <a href="https://pixabay.com/users/maxxgirr-3565425/?utm_source=link-attribution&amp;utm_medium=referral&amp;utm_campaign=image&amp;utm_content=2679490">Maxx Girr</a> from
Every vehicle has a specific economical speedGasoline prices in the U.S. hit a record high of $4.33 this weekVarious Fuels USThese hypermiling techniques will save you a lot of money on fuel, despite the sky-high pricesThese hypermiling techniques will save you a lot of money on fuel, despite the sky-high pricesThese hypermiling techniques will save you a lot of money on fuel, despite the sky-high prices
We know all sorts of tips and tricks to make our cars sip as little fuel as possible, but in the face of the $4-$5 per gallon of fuel, nothing seems to help. That’s because, unlike transportation companies, which are geared toward efficiency and making money, our minds are wired for pleasure. Even as we complain about high fuel prices, we step hard on the gas pedal only to push hard on the brake pedal 500 feet down the road. We can’t help it, even though we know for sure that more speed equals more fuel.

So, at least in theory, we’re more than willing to pay more (even though bitching about high fuel prices) just to keep the same level of enjoyment while driving a car. We do the same when we want to keep the same level of misery, too, like during a road rage episode, which is really strange. Aggressive driving spends a lot of fuel because this implies a lot of accelerating and braking, sometimes unnecessarily. And yet we do it so often.

So, you guessed it, the best way to save fuel is to keep going at a constant speed for as long as possible. This is obvious, as accelerating means burning more fuel while braking means losing the energy that you spent fuel on to build up. So, we want to cruise at a constant speed to save fuel, but what would be the optimum speed that allows us to save the most fuel? All while avoiding crawling on the road, which can be both unsafe and inefficient.

Every vehicle has a specific economical speed
Photo: Image by Peter H from Pixabay
You might be tempted to think that you save the most fuel by going as slow as possible, but a car does not function like that. In fact, it’s the opposite. A vehicle’s engine still burns fuel at 0 mph because it needs to drive all those equipment like air conditioning and alternator to charge the battery and power everything, from lights to the radio. This is why modern vehicles feature start&stop systems to cut the fuel while standing still at redlight or in a traffic jam.

As you imagine, at 0 mph, your fuel efficiency would be bad, really bad, like 0 mpg. Just by moving a little, you will significantly improve your mileage, even from 0 to 1 mpg. But that’s not the point, as the engine still uses more gas for powering ancillary equipment than for moving the car. So you get the idea: the faster you move, the more efficient your vehicle becomes. After all, you want to offset all those losses not related to moving.

Unfortunately, this goes only a short way, as, by the time you gain enough speed, other things will start ruining your fuel economy. The tires rolling and compressing is one of them. That’s why one of the greatest tips for more fuel economy is making sure the tires are properly inflated. Keeping your vehicle as light as possible by getting all the unnecessary stuff out of the trunk also helps.

By the time you get really fast and start to enjoy driving, another problem called wind drag is becoming prevalent. That’s because your car will need to push against the air surrounding it. The faster you go, the more will the air oppose moving. Stick your hand out the window at speed, and you’ll get the idea. At this stage, more speed does equal more fuel. The drag rises exponentially with speed, so a small gain in speed will burn quite a lot of fuel above a certain speed.

These hypermiling techniques will save you a lot of money on fuel, despite the sky\-high prices
Photo: Pixabay.com
This is why we need to find the sweet spot in driving speed where we can still drive fast while not spending that much on overcoming air drag. This is not easy, as this depends on a lot of factors, including your vehicle’s fuel economy and how aerodynamical its shape is. For passenger cars, this optimal speed tends to be significantly higher. A pickup truck would burn more fuel starting at a lower speed because the drag resistance is significant.

For most light-duty vehicles, the optimum speed is somewhere between 40 mph (64 kph) and 60 mph (97 kph). Passenger cars would be more efficient at higher speeds, probably above 50 mph (80 kph), while pickup trucks and SUVs will have a lower economical speed. But either way, bear in mind that this only goes for driving at a constant speed.

Driving slower might save money on fuel, but some will argue that the time is also money. It’s true, but the evidence shows your commute will only get a couple of minutes longer, too few to make any difference. Let’s run the numbers for a 40-mile commute, which should take 34 minutes at a constant speed of 70 mph (113 kph). Lower the speed to 60 mph, and you’ll spend on the road 40 minutes, or six minutes more. How much money would that be?
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About the author: Cristian Agatie
Cristian Agatie profile photo

After his childhood dream of becoming a "tractor operator" didn't pan out, Cristian turned to journalism, first in print and later moving to online media. His top interests are electric vehicles and new energy solutions.
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