How to Get More Miles Per Gallon
 

This article is written by Bob Chapman

What's the single best way to save gas ?

Drive less. Whenever possible and practical, carpooling and mass transit are great ways to conserve fuel. You should also plan ahead when you know you have several errands to run. Combine errands, and mentally plan the shortest route possible. For quick trips around the neighborhood, walk or ride a bicycle. You'll save gas, and as a bonus, get some good exercise. 
 

Will I get better mileage by using gasoline with a higher octane rating ?

Octane does not directly affect gas mileage, but it can affect your car's overall performance. The octane rating of gasoline is a measure of its ability to control conditions commonly known as "knocking" and "run-on." Allowed to persist, knocking can damage your engine. Start with the octane level recommended in your car's owner's manual. Move up to the next level if you experience knock or run-on. Then practice as many of the suggestions in this book as you can to improve your gas mileage. 

Can good maintenance save gasoline ?

Yes. A car that's in tiptop running condition is a better gas saver than a car that isn't. A tune-up for a car that's badly out of tune (even a newer car) can increase your mileage by as much as 20 percent. Also, a car with incorrect wheel alignment will have increased road resistance which wastes gas. Have your technician check your car's alignment and adjust it if necessary. Even if you're not a do-it-yourselfer, there is gas-saving maintenance you can do on your own. For example, check the air pressure of your car's tires at least once a month to be sure they're inflated to the pressures recommended in your owner's manual. Underinflated tires are a major cause of poor fuel economy, costing you up to one mile per gallon. Cars equipped with radial tires get better mileage than cars equipped with bias-ply tires. But you should never mix the two types. It's also important to have a clean air filter. Clogged, dirty filters cut off your engine's air supply. This causes a higher fuel-to-air ratio and increases gasoline consumption. Change the air filter at the interval recommended in your owner's manual or if it looks dirty. 
 

What is "high-efficiency" driving ?

You've heard of high-efficiency appliances, the kind that get the job done using less power, which in turn saves on utility bills. High-efficiency driving simply applies that concept to how you drive. Here are a few things you can do to become a high-efficiency driver and get better gas mileage: Ease up on your right foot Gentle acceleration cuts waste. Pretend there's a glass of water on the dashboard and you're trying not to spill any of it. The same applies for braking. When you know you're coming to a stop at an intersection, take your foot off an the accelerator and let your car coast in gear. That way the car's momentum, instead of extra gasoline, gets you to the intersection. Practice "steady as she goes" driving Speeding up, slowing down, and speeding again eats away at gas mileage. Whenever possible, position yourself in traffic between clusters of cars so you can keep a steady speed. In bumper-to-bumper traffic, it's much better to inch along than to stop and go all the time. Maintain a steady speed by using cruise control (if you have it) when out on the road. But not when traffic is heavy or when traveling hilly terrain; cruise control is less efficient under these two driving conditions.

Watch your speed When traveling at a steady speed, most cars get their best gas mileage somewhere between 35 and 45 miles per hour depending on the car's engine and transmission. Driving at lower or higher speeds will use more gasoline {see the chart on the second page of this booklet). In a typical car, driving at 55 mph rather than 65 mph can increase gas mileage by 3-5 miles per gallon.  

Learn proper shifting techniques The idea is to get into high gear quickly without straining your engine. If you drive a 5-speed manual transmission, depending on your vehicle, you may even be able to skip gears, shifting from first gear to third gear and then from third gear to fifth gear. In a vehicle equipped with automatic transmission, gentle acceleration helps you into high gear sooner. In some cars, so does "letting up" just a little on the accelerator. 

Lighten up A heavy load can lower gas mileage. Remove any items you're carrying around that are unnecessarily adding weight (bowling ball, unneeded tools, etc.)  

Cut down on your A/C Your air conditioner is one of the biggest drains on your engine's power. Not using it will cut your gas consumption by 5 to 20 percent depending on the car and how you drive. Driving down the highway with the windows open increases drag, which decreases your gas mileage, but not nearly as much as using the air conditioner. 
Don't worry, be happy You're in no shape to be behind the wheel if you're in a bad mood or downright angry. You're likely to take it out on the accelerator. Not only can that be wasteful, it isn't very safe. Don't go for a drive to vent your anger; go for a walk instead. 

What is the worst mileage my car could possibly get, and how can I prevent it ?

Believe it or not, the worst mileage your car can get is 0 miles per gallon. That happens when your car is idling, but not moving. In this case, it may be a good move to turn off the engine. Restarting uses about the same amount of gas as idling for 30 seconds. So if you find yourself waiting for a train to pass, or for your burger at the drive-thru window of a restaurant, try to estimate how long you'll be stopped. If it's more than 30 seconds, shut off the engine to save a little gas and pollute the air less.


Read More Automotive Articles

Can motor oil affect gas mileage ?


Yes. For better gas mileage, use a multigrade motor oil recommended by your car's manufacturer. Also, select an energy conserving (EC) oil identified by an Energy Conserving or Energy Conserving 11 imprint in the API (American Petroleum Institute) symbol on the motor oil container. An EC-rated multigrade oil can improve your gas mileage by 1.5% over a typical single grade motor oil. An EC II rating indicates an improvement of 2.7% over the single. grade oil.  Remember, it's not good to jump at one estimate just because it's the lowest. A lower price may mean shoddy work. Know what you are paying for and what the estimate includes. In short, make sure you're comparing apples to apples when comparing estimates. 

I've seen ads for fuel-saving products that attach to my car's engine or
go into the gas tank. Do they work ?

Be wary of products sold as fuel savers. According to the Federal Trade Commission, not one of the many devices tested or otherwise evaluated to date by the Environmental Protection Agency has been found to significantly increase fuel economy. 

Do I have to buy a new car to get better gas mileage ?

No. You can practice the tips in this book to get better mileage driving the vehicle you now own. But if you have new-car fever, don't overlook good mileage when deciding which car to buy. Certain equipment carries with it a greater "mileage price" - air conditioning; power steering; larger, more powerful engines; automatic transmission; and 4-wheel drive lower your fuel economy. Compare the EPA mileage estimates displayed on the price sticker of new cars. And ask your dealer for a copy of The Department of Energy's Gas Mileage Guide. 

How do I figure out how much my car uses ?

Each time you buy gas, fill the tank completely (though not to overflow) and note the number of gallons. Then write down the miles showing on your car's odometer. Divide the number of miles you drove since your last fill-up by the number of gallons you put in. For example, suppose you fill your tank with 14 gallons. You've driven 350 miles since your last fill-up. So 350 divided by 14 is 25 miles per gallon (mpg). It's a good idea to keep track of your car's gas mileage. A sudden increase in fuel consumption may signal the need for a tune-up or repairs. Of course, driving situations vary, and that can cause your mpg to vary. Ideally, you should adjust your driving to fit those different situations to improve your overall fuel economy. 

Courtesy Shell  Oil