Smart SpendingSmart Spending

4 gas-saving 'tips' that don't work

Advice such as buying gasoline in the cool of the morning or leaving the tailgate down has been tried -- with disappointing results.

By MSN Money Partner Mar 12, 2012 3:26PM

This post comes from Matt Brownell at partner site MainStreet.


MainStreet on MSN MoneyThere are a lot of smart ways to save on gas. For instance, you can use a website such as GasBuddy to find cheaper gas stations in your area, buy a more fuel-efficient vehicle or drive less aggressively so your car uses less gas.


These are all proven methods for reducing how much you need to budget for gas, but there are other widely used methods that don't pass the smell test. Here are a few.  (Post continues below.)

Buy gas early in the morning.

Gasoline is denser at colder temperatures, so the theory here is that if you fill up early in the morning while it's still cool out, you'll get more bang for your buck -- a gallon of gas bought cold will expand to be a little more than a gallon when it gets warmer. But as we explained in our look at common car myths, gas at gas stations is stored in underground tanks, where the temperature varies a lot less than it does on the surface. As such, there's going to be little to no perceptible difference in the density of the gasoline whether you buy it in the morning or at night.


With that said, it still might be worth it to fill up in the morning because, given how quickly gas prices have been rising, you might find that the price has gone up by a few cents by the time you get back to the station that evening.


Overinflate your tires.

Yes, it's true underinflated tires lead to decreased mileage, so you should make sure your tires are properly inflated for fuel efficiency and safety reasons. But some people have taken that to the logical extreme by inflating their tires beyond the recommended pressure, the theory being that an overinflated tire will have a smaller contact patch with the pavement and thus less resistance. Alas, it turns out that's not really the case: Popular Mechanics tested this one out and found almost no difference in gas mileage between 32 psi inflation and 45 psi.

Turn off the air conditioning and lower the windows.

The theory here is that air conditioning draws energy from the engine, and that lowering the windows reduces drag. Thus, on a warm day you should turn off the air conditioning and lower the windows to boost your gas mileage. Unfortunately, there appears to be little truth to this method: Edmunds tested it back in 2005 and found that the mileage was the same no matter which method they used to cool themselves. If it's hot out, don't hesitate to blast the A/C.


Leave your tailgate down.

Many pickup truck drivers will leave the tailgate down, the idea being that having it up will "catch" the air flowing over the truck, acting as a sail that increases drag and makes you burn more gas. But the Discovery Channel's hit show "MythBusters" tested this one and then retested it and found that fuel efficiency was actually a little better with the tailgate up. That's right, keeping your tailgate open actually made things worse, and putting a cover on the pickup truck's bed had no real impact on fuel efficiency.


More on MainStreet and MSN Money:

Mar 23, 2012 7:58AM
Having followed politics for over 40 years, I can state unequivocally that there is more gas to be found in Washington DC than any other place in the entire world.
Mar 23, 2012 3:43AM

So true. The wind resistance over 60MPH starts to really suck the gas, that doesn't stop them from doing 80. I have to disagree with starting off slow, not that I think you should gun it. You need to know the torque curve of your engine and accelerate at the proper rpm range. If 20% of us would drive motorcycles we would eliminate traffic, at least thats what the computerized study showed. Most of us waste too much gas in traffic. I wish they could save us some money by timing the lights better, and not let them turn red when NOBODY else is even around.

Mar 23, 2012 7:08AM
What difference will it make?  All of our efforts to save gas are in vain if the gas merchants keep gouging the price.
Mar 23, 2012 9:32AM
I've found that getting out of the car and running along side it saves gas.  That's because my fat **** isn't in it.
Mar 23, 2012 8:28AM
The A/C can make a difference depending on what kind of vehicle you drive.  If you are driving a full size SUV with a V8, you have a lot of extra power not being used, so the A/C will not make a difference.  But if you drive a compact with a 2.0 4cyl, the A/C will use a noticeable percentage of the power.
Mar 23, 2012 7:05AM
I like how they reference mythbusters for one test and a different lab for another. Mythbusters did the A/C mileage test and found that below 55mph it is more fuel efficient to roll down the windows and above 55mph to use the A/C and AT 55mph the efficiency curves meet so it wouldn't matter.
Mar 23, 2012 9:34AM
mrsgin, Did you say you change your oil every 1000 miles??? While you "save" at the pump,
I hope you enjoy "wasting" your money with your oil change. Every 1,000 miles is beyond overkill.
Heck for those who know, every 3, 000 miles is overkill as well. I have religiously changed my oil 
every 7,500 miles, and have well over 160K miles on my car, without issue.
Mar 23, 2012 11:44AM
If you really want the price of oil to drop, push for a law that would make the traders take delivery and hold for 30 days before they could sell, unless it was an oil refiner buying directly, and he could only sell the refined product. That would stop all the speculation in the market and drop oil by 50%
Mar 23, 2012 8:44AM

Keeping tire pressure at the manufacturer's recommended setting is a big deal.  Over inflated tires can be just as hazardous as under inflated tires, degrading the handling characteristics of the vehicle.  It can make the difference between successfully negotiating an emergency situation and losing control of the car.


Everybody loves a good conspiracy theory, and would like to think that auto manufacturers are somehow in cahoots with big oil companies to get consumers to burn more fuel.  Even if car makers were conspiring, they would still have to build cars that satisfied their customers' needs, or they'd lose market share to their competitors.  Conspiracies never work because there is always somebody that sees the opportunity to gain by not following the pack.  Even OPEC can't keep all its members in line to fix prices.


So, keep your tires at the recommended pressure setting and enjoy the optimum handling and most comfortable ride characteristics for your car.  Quit worrying whether or not you could be getting 1/100th MPG better economy.

Mar 23, 2012 8:48AM
Buying a vehicle at the right time will save real money. If a person is in the market for a 4 wheel drive truck, wait until gas prices are high. If you're in the market for a fuel miser, buy it when gas is cheap. With a little luck and good timing you might save enough money to pay for a year or two of gas.   
Mar 23, 2012 8:43AM
I bought my F-150 new in 2006, it got about 18 mpg on the hiway. A guy was hired on our job who had one also, he had a toneau cover on it, and when he opened his tailgate his tools were dry, mine weren't. (I'm a bricklayer) So I bought one, and not only did my tools keep dry, I immediatly picked up 2 mpg's. That has been the best $300 I've ever spent, and adds to the looks of the truck.
Mar 23, 2012 6:31AM

In the article the writer writes that "Turn off the air conditioning and lower the windows" makes no difference in gas mileage.

Here again, the writer should refer to "mythbusters", who did a test on their show that showed that running your vehicle with the AC off did indeed make a 'noticeable' difference in fuel consumption. This writer really should investigate more thoroughly before posting such articles. (Or maybe they "want" us to use more fuel. to deepen our dependence.

Mar 23, 2012 10:42AM

Our Government is the biggest waste of gas that we have, no I’m not kidding around. Ethanol is the one biggest waste of gas mileage; on my Honda CRV it cost me in mileage. When I can find gas without Ethanol I average 27 miles per gallon but the rest of the time with Ethanol in my gas I only get 17 miles per gallon. Of course it does affect my 2010 Toyota Tundra 4 wheel drive but it is not as measureable because of the fact it only gets 15 per gallon with Ethanol as compared to 16.75 without. Ethanol other than creating a huge increase in food prices I don’t see any benefits! This was removed from our tanks back in the 80’s because of the fact that it had absolutely no benefit other than increasing food prices and reducing fuel efficiency.

Mar 23, 2012 10:30AM


I have two vehicle that have 5.7L Hemi engines with MDS in them. I get 20% to 25% BETTER GAS MILEAGE using NON-ETHANOL FUEL. My '09 Challenger has gotten as much as 31mpg highway not running the ac. The best it ever did with ethanol fules was 23-24mpg. Not many gas stations have it. Look for it and see the DIFFERENCE! Then write your congressman to ban ethanol fuels that are making your grocery bill skyrocket. I have read article that say it takes a gallon of diesel fuel to grow enough corn to produce a gallon of ehtanol. Where is that benefiting our dependence on foreign oil.



Mar 23, 2012 9:34AM



Gas prices are controlled by the price of oil, day traders at the stock market control the price of oil, as they do with McDonalds stock, etc. No President has the power to tell you or anyone else what commodity or stock you can buy or sell in the stock market. Thats like blaming the sales clerk for the price of your new shoes. Maybe you should learn how the commodity market works??

Mar 23, 2012 12:11PM
Eliminate congress & the senate! They're ALL thieves and liars!
Mar 23, 2012 9:46AM
Yes real gas savings could be earned if townships set the traffic lights up to allow as much continued travel without un-necessary stoping for lights. If you are on a divided road, the lights should be timed that as long as you do the speed limit, +/- 5mph, all the lights should stay green for you to minimize idle time. Also lights should be motion sensitive. Why make motorists stop for a light when there is no traffic the other way. It makes no sense at all. These functions are available, after all fire trucks can remotely change light signals so why can't townships figure this out. My only guess is either they don't care about energy loss or else there is some other hidden agenda to earn ticket money for people pushing light signals to bypassing having to stop.
Mar 23, 2012 6:10AM
mythbusters actually found that gas mileage is best if the tailgate is removed. please be a little more thorough.
Mar 23, 2012 4:31AM

I can not say what works for people on gas saving driving but do know for a fact several things that do for me. Keeping my tires at a certain pressure does and regularly check them to see their at that pressure. Shell gas and I have no idea why gets me more miles out of a gallon. I experimented with Irving,Mobil,Exxon,Texaco,Gulf and Citco. A can of dry gas every month or two in the winter months since I drive less then most and keeping my car regularly checked twice a year at a good garage what used to be a tune-up and now they do not call it that,where the oil and filter are changed,air filter if needed and what ever is needed including fluid and grease wise. A complete car check. One at inspection time and the other six months later. During winter keeping my car full or close to full  helps my car run better as well as water out of the gas tank, filters and line.

 As I said I do not know what works for other autos or what wive's tales they claim work or not. But I feel it has to do with a lot of things,from what type of auto,where in the country one lives and the type of driving long or short distances etc..

Mar 23, 2012 9:43AM
sr you are not real bright it has been proven over and over a clogged air filter also causes a loss of horse power besides a loss of mpg it doent not matter how old the car it is still a internal combustion engine!
Please help us to maintain a healthy and vibrant community by reporting any illegal or inappropriate behavior. If you believe a message violates theCode of Conductplease use this form to notify the moderators. They will investigate your report and take appropriate action. If necessary, they report all illegal activity to the proper authorities.
100 character limit
Are you sure you want to delete this comment?


Copyright © 2014 Microsoft. All rights reserved.

Fundamental company data and historical chart data provided by Morningstar Inc. Real-time index quotes and delayed quotes supplied by Morningstar Inc. Quotes delayed by up to 15 minutes, except where indicated otherwise. Fund summary, fund performance and dividend data provided by Morningstar Inc. Analyst recommendations provided by Zacks Investment Research. StockScouter data provided by Verus Analytics. IPO data provided by Hoover's Inc. Index membership data provided by Morningstar Inc.


Smart Spending brings you the best money-saving tips from MSN Money and the rest of the Web. Join the conversation on Facebook and follow us on Twitter.