How to Save Money on Gas — A Guest Post

by Katy on May 24, 2009 · 11 comments

The following is a guest post from Alison Wiley of diamond-cut Enjoy!

Katy Wolk-Stanley

“Use it up, wear it out, make it do or do without.”


The way we drive has a huge impact on what we spend on gas. The cool thing about saving money on gas by using less of it, from the perspective of the diamond-cut life, is that we reduce our carbon emissions at the same time. And all of us would prefer to subsidize our own bank accounts rather than the profits of oil companies.

Drive slower and smoother. A gentle right foot when driving around town can cut fuel consumption by 27-35%, according to This can mean getting 31 mpg instead of 22 mpg. Specific examples: accelerating slowly from green lights and decelerating slowly when approaching red lights. The smoother a car’s overall motion, the more gas money we save. The more herky-jerky the motion, with faster starts and stops, the more gas money we are throwing away.

Carpool. When I carpooled to work with five others, we each spent fifty cents per gallon of gas by dint of taking turns driving (based on current gas price of $2.48/gallon). Now that I’m in a vanpool, I’m also extending the life of my vehicle by driving it so little.

Streamline your vehicle. The aim is minimal wind resistance. Keep the windows and sunroof closed, especially at higher speeds. An engineer I know told me he gets 5-7 more miles per gallon when he takes the rack off the top of his Subaru Outback. “It’s the wind resistance, much more than the weight,” he reports.

Use your body for short trips: bike or walk. This is easiest and the most fun in nice weather. Treat most destinations close to you, whether groceries, social opportunities, dry-cleaning or restaurants, as your top picks. Even if they charge a bit more, using no gas to get there may make it the cheaper choice overall. To get a sense of how walkable your neighborhood is, use this “Walk-score ” website.

Use cruise control on the highway. The single, consistent speed can improve mileage by almost 14%. It’s easy to forget to use cruise control, if I am any example; I should put a post-it reminder on the dashboard.

Pick up the phone. The humble telephone is a powerful money-saving device. Does the Home Depot across town actually still have that item you want in stock, or are you just hoping it does? It takes a few minutes to call and ask them to check for you — but it takes much longer, plus several dollars in gas, to drive over and check yourself.

Try using public transit. In many cases, the fare is less than you’d pay for gas. If you like to read, work or knit while riding, you can come out ahead overall in time-use. In congested areas where parking is difficult, transit may be faster than driving alone.

Reconsider the air conditioning. Using it reduces fuel economy by 10-20%. However, that applies to in-town driving. At highway speeds it’s more cost-efficient to roll the windows up and use the a/c, due to the lowered wind resistance of being more streamlined.

Turn off the engine rather than idle for 20 seconds or more. I’m amazed by people leaving their engines on, burning precious gas, while waiting four minutes for a bridge here in Portland to let a ship through. Also, don’t “warm up” your vehicle for more than 20 seconds. It’s a myth that modern engines get any benefit from this.

Find places for privacy and solitude other than your car. Many people unknowingly use their cars for needs that have nothing to do with transportation. The needs are legitimate and human; using cars and gas to meet them is costly both to the person and our shared planet. Nature, libraries and a designated room in one’s home can be good places for privacy and solitude.

Make only right turns. Doing trips this way takes some forethought, but again, our gas-tanks literally pay us for using our brains. (I must modestly admit I had figured this trick out many years before UPS did :).

Build your collateral in things other than your car. Cars (unless they are hybrids, apparently) depreciate rapidly in value. Spending money on a car’s appearance, performance or accessories may not be in your best interest as much as if you were to invest in your relationships, education, character, spiritual life, home, garden, investing skills, etc.

Keep your tires properly inflated and your engine tuned. These practices improve your mileage by 3% and 4% respectively, according to

Declutter your vehicle. Less weight means less gas used to haul it around. I finally took our winter chains out of our trunk last Friday. (I left the first-aid kit and gallon of emergency water in, though.)

Photo courtesy of Sonny Side Up

{ 11 comments… read them below or add one }

Foosle May 24, 2009 at 12:23 pm

“make only right turns” isn’t always the less-gas answer. “free” left turns that cut out 20 blocks of travel (there are many wonky no-turn areas in my neighborhood – one wrong right turn and you’re trapped for a mile at least). Or Left turns in an area you know has good flowing traffic (ie – has good open spots so that you aren’t sitting there waiting) is also better than a right turn that would lead you around a few blocks. With a few well-chosen left turns, I can condense my 15 errands into a short drive, whereas if I did only right turns, it would turn into miles of driving.

Also, “right turns only” can force you to use side streets instead of arterials, thus screwing up traffic flow for those on side streets and putting yourself and others into more danger (maybe your right turns have you circling an elementary school at let-out time?). There’s a reason arterials have lights, multi-lanes, well-seen crosswalks etc – they’re built to handle the flow, side streets aren’t.

Along with trying to use less gas, one should consider the ramifications of ones actions on the world around you. It’s not just you out there driving.


hustler May 24, 2009 at 2:57 pm

Wow. Most of these I already knew, but a couple really hit home. Pick up the phone, and find other places for privacy and solitude to be specific. I am guilty of both of these. Thanks for the tips!


Fairy Dust May 25, 2009 at 7:36 am

I was so mad at myself yesterday. I specifically wanted to drive over to Target to drop off a Rx (to get a free $10 gc for transferring the Rx), and I got there at 1:31pm, exactly one minute after the pharmacy closed for lunch, which is something I always forget about. Complete waste of time and the gas to drive over and then drive home. I felt (a) stupid for not calling first, and (b) angry that I hadn’t thought of something else to do in that general area that could be my back-up errand so the trip wouldn’t have been a complete loss.


Kris-ND May 25, 2009 at 12:31 pm

This is a frustrating topic to me, for a few reasons. People make assumptions about my dh and I because we drive a 4wheel drive vehicle. Often, they don’t even bother to look at our license plate, and think “oh, they live in ND…they might need a 4wheel drive vehicle in the winter” it is just “You have no right to drive that vehicle” NOT all of course, but the times we have been in Minneapolis for example, we have run into “looks”…sigh

I live in the Badlands. I cannot, and I mean it is impossible, to get up my driveway in the winter w/o having a 4 wheel drive vehicle. Our 17 yo daughter drives a smaller car, but in the winter, she must borrow our other 4 wheel drive vehicle(that is only driven when one of my other drivers must go to town in the winter)if she needs to go into town. We cannot afford to buy a hybrid SUV or convert our current SUV to a hybrid…it is just out of the range for most people out here.

People often times forget that somebody has to grow that wheat, etc that we use to make bread. You cannot plop a 600 acre wheat field in the middle of a city so you can take public transportation, and those vehicles don’t run on fairy dust, so they require much gasoline. Rural states that are farming/ranching states, have, just by the nature of the acreage used for crops, long drives between towns/cities, BUT, I will tell you, that those of us who live rural, are very good at combining trips, much better than those that live in cities sometimes :). If you live in a city and you forget something at the grocery store, well, you just pop over. I have a 18 mile each way trip to get into town, and there is nothing between my home and town, so we don’t just pop over to a store because we forgot Our routine is to take care of as many things as possible with as few trips as possible. My dh works in town, so if there is something I need at say Walmart, I give him the list to pick up on his way home, so I do not make a special trip. I am able to go to my library’s catalog online, and mark down the books I want and reserve them, so all he has to do is walk in and check them out.

I believe in supporting the local community, but again, I try and do as much as I can in one visit. I schedule all our dental appts and other appts on the same day and then run the other errands I need in town after or before those appts.

I have epilepsy, and it is a minimum of a 2hour drive to get to the closest neurologist, so when I have to go, we make a list of the things to get that are not easy to get here, and make the trip as short as possible, planning the quickest route from place to place.

All this to say, that nobody loves the land more than the people who depend on the land for their livelihood and to pass down through the generations. Our air and water is wonderful, in fact, I think we have the cleanest air in the entire country(or up in the top 5), so I just ask for some understanding when you see an SUV with a Montana or a Wyoming, North Dakota, South Dakota plate, that there might be a reason they are driving an SUV 🙂


Rachel May 25, 2009 at 12:37 pm

They had an episode on Mythbusters a while back about using ac vs. rolling down the windows. It was neat.


Manuel May 25, 2009 at 12:57 pm

Using the cruise control can actually be detrimental, especially when you are driving in an area with many smaller hills and valleys.

What happens is that your cruise control will overcompensate for going up a small hill by shifting down, increasing engine RPM and thus fuel consumption. Instead, when you drive in “manual” mode, you’d just go up the hill by reducing gas pedal pressure, loosing a bit of speed, but maintaining the gear, thus not burning gas at a higher rate.

Of course, curse control is great when you are on a mostly flat highway, but if you are going up and down a lot of 100-300 feet hills, your gas mileage will suffer if using cruise control.


Canadian Kate May 25, 2009 at 2:16 pm

We are now two in our family so I’ve taken one of the two middle row seats out of the van to cut weight. This leaves one middle seat for our son when he is riding with us. And since my rear bench seat is fixed in the car, I still have a 6 seatbelts if I’m unexpectedly need to give a rid to others. If I’m driving 7, I usually know well in advance so can put the 7th seat back in. (We even leave that seat out on vacations when we are 5 in the car since my dd and dsil are happy to sit together in the back.)

As for a/c vs. windows, I have a ScanGauge in my car that gives me exact fuel burning stats in real-time. On a recent highway trip I was using it to test the a/c vs. Windows mileage. They were basically equal. BUT with no windows open or a/c and just fresh air blowing in through the vents, cut my gas mileage by over 10%. I was very impressed (and cycled the a/c on and off as a result, only using it when I was getting too hot.)

As for using cruise-control, that is a given with me. I have a very heavy foot (spotted by my driving instructor and seconded by my driving tester) and I’ve used my cruise control to counter-act that. As a result, I’ve never had a moving violation. So cruise control has saved me both gas money and ticket money over the years!

I have a 2003 Honda Odyssey and on the highway I get better than 26 mpg which is better than the EPA rating for the car when it was new.


Sierra May 25, 2009 at 10:14 pm

My personal, crazy, gas-saving technique was to move out of the suburbs into an urban neighborhood a short walk from my husband’s office, and to change my own career so I can work at home. We’ve gone from spending about $600/month to $60/month on gas for our van.


Chuck May 27, 2009 at 6:14 am

Good guest post (and good blog, been reading since JD linked you a few weeks ago).

From the perspective of an engineer with a pretty automotive-heavy background, I can add to and expand upon the information above a bit. While commuting in my old Mustang for years (currently parked), a car the EPA now estimates at 15mpg city, 22 highway, I was consistently able to average 21 to 22mpg commuting to work through a tunnel with a 20 minute delay both ways, and often averaged 25 to 27 mpg on the highway. My current commuter, a late model Miata, sees 30/32 despite an EPA estimate of 20/26. I am by no means a slow driver.

The first and most important paragraph is the advice to drive slower and smoother. However, many people misinterpret and misapply this advice into driving as if they had an egg under the gas pedal – I’ve actually heard this exact rotten (pardon the pun) advice given. This can be beneficial at times, but can just as easily reduce your gas mileage at other times.

It all comes down to basic physics. There is a certain amount of energy associated with your vehicle at a given speed, depending on its mass. In order to get to that speed from a stop, we have to generate that energy using the engine – and with normal efficiencies, you burn two tablespoons of extra gas for every tablespoon that actually gets turned into usable energy. In order to stop, we have to get rid of that same amount of energy, usually by burning it off into heat using the brakes. Brakes, unlike engines, are perfectly efficient at what they do. The first lesson to learn is to avoid using the brakes (or engine braking by downshifting, which is just as detrimental to mileage) whenever it’s possible to do so safely – every watt-hour of energy you burn braking represents three watt-hours of energy coming out of your gas tank. Instead, coast early when you know you’re approaching a stop, letting the wind and rolling friction slow you down – this is energy you’d have to spend anyway, and when coasting to a stop, you can basically consider it “free” energy, as opposed to burning gas to generate this energy and then hitting the brakes to burn it up and stop.

The second place you lose energy (and gas), beyond braking, is in friction. This comes in the form of rolling friction from your tires, and air drag. At cruising speeds, particularly on the highway at around 45mph and up, drag is far more important than rolling friction. Drag increases with the square of your speed. In other words, accelerating from a 60mph highway speed to 65, despite being only 8% faster, can cost you up to 17% more per mile (it will fall between 8% and 17%, largely depending on how much of your energy burn is rolling friction and how much is drag). This equation holds true no matter how aerodynamic your car is – you always lose energy disproportionately quickly as your speed goes up. Lesson two, therefore, is to slow down a bit on the highway. Even a few miles per hour, if consistent, will make a difference.

As for the egg-under-the-gas-pedal driving style, your engine is actually normally most efficient at around two thirds power, somewhere right around the middle of its operating speed. This is efficiency in producing energy to accelerate, not efficiency in terms of cruising, where other things come into effect. In reality, you have to produce the same mount of energy to get to a certain speed, whether you do it quickly or slowly. All other things being equal, it’s better to produce that energy as efficiently as possible, which means letting your engine work it its efficiency band. In other words, go.

In summary, when you start off from a stop, look ahead. If there’s another traffic light or stop sign right in front of you, take off easy, and don’t bother trying to get to maximum speed – the faster you go, the more you’ll use your brakes at the stop, and the more energy you’ll waste. If there’s nothing ahead of you but miles of open road, put your foot in it and get up to cruising speed – your wallet and car will thank you. If you want to save, lower your cruise speed, since this is what determines your highway mileage, not how grandmother-slow you can get up to that speed. It’s really that simple.

Happy motoring!


kimberly drives May 31, 2009 at 6:19 pm

I am teaching my little brother how to drive. But I also emphasize on how to drive efficiently without running your fuel tank empty.


Ursala @ Diamond-Cut Life March 24, 2014 at 7:12 pm

I love the comments about avoiding using the brakes, keeping the windows up and just blowing air to stay cool until it gets too hot, and not going too fast on the freeway. These are great examples of how it can make a big difference just do not do something, rather than focusing only on what can be done. Thanks for sharing ways to make a difference with small choices.


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