Gas Saving Tips

1. Use the right oil. You can improve your car's gas mileage by 1 percent to 2 percent by using the manufacturer's recommended grade of motor oil. Go for the motor oil with the words "energy conserving" on the API performance label. This oil contains friction-reducing additives.

2. Accelerate slowly when starting from dead stop. Don't push pedal down more than 1/4 of the total foot travel.

3. Don't start and stop engine needlessly. Idling your engine for one minute consumes the gas amount equivalent to when you start the engine.

4. Avoid prolonged warming up of engine, even on cold mornings - 30 to 45 seconds is plenty of time.

5. Traveling at 55 mph will give you up to 21% better mileage when compared to speed limits of 65 mph and 70 mph.

6. Traveling at fast rates in low gears can consume up to 45% more fuel than is needed.

7. Keep windows closed when traveling at highway speeds. Open windows cause air drag, reducing your mileage by 10%.

8. Drive steadily. Slowing down or speeding up wastes fuel.

9. Think ahead when approaching hills. If you accelerate, do it before you reach the hill, not while you're on it.

10. Stoplights are usually timed for your motoring advantage. By traveling steadily at the legal speed limit you boost your chances of having the "green light" all the way.

11. Regular tune-ups ensure best economy; check owner's manual for recommended maintenance intervals. Special attention should be given to maintaining clean air filters... diminished air flow increases gas waste.

12. Inflate all tires to maximum limit. Each tire should be periodically spun, balanced and checked for out-of-round. Radial designs are the recognized fuel-savers; check manufacturer's specifications for maximum tire pressures.

13. Remove excess weight from trunk or inside of car - extra tires, back seats, unnecessary heavy parts. Extra weight reduces mileage, especially when driving up inclines.

Note: Cost savings are based on an assumed fuel price of $3.22/gallon.

Drive Sensibly

Aggressive driving (speeding, rapid acceleration and braking) wastes gas. It can lower your gas mileage by 33 percent at highway speeds and by 5 percent around town. Sensible driving is also safer for you and others, so you may save more than gas money.

Observe the Speed Limit

While each vehicle reaches its optimal fuel economy at a different speed (or range of speeds), gas mileage usually decreases rapidly at speeds above 60 mph.

As a rule of thumb, you can assume that each 5 mph you drive over 60 mph is like paying an additional $0.20 per gallon for gas.

Observing the speed limit is also safer.

Remove Excess Weight

Avoid keeping unnecessary items in your vehicle, especially heavy ones. An extra 100 pounds in your vehicle could reduce your MPG by up to 2%. The reduction is based on the percentage of extra weight relative to the vehicle's weight and affects smaller vehicles more than larger ones.

Avoid Excessive Idling

Idling gets 0 miles per gallon. Cars with larger engines typically waste more gas at idle than do cars with smaller engines.

Use Cruise Control

Using cruise control on the highway helps you maintain a constant speed and, in most cases, will save gas.

Use Overdrive Gears

When you use overdrive gearing, your car's engine speed goes down. This saves gas and reduces engine wear.

Test Performed By Edmunds.com

Test #1 Aggressive Driving vs. Moderate Driving

Result: Major savings potential

The Cold Hard Facts: Up to 37 percent savings, average savings of 31 percent

Recommendation: Stop driving like a maniac.




Test #2 Lower Speeds Saves Gas

Result: Substantial savings on a long trip

Cold Hard Facts: Up to 14 percent savings, average savings of 12 percent

Recommendation: Drive the speed limit.




Test #3 Use Cruise Control

Result: Surprisingly effective way to save gas

Cold Hard Facts: Up to 14-percent savings, average savings of 7 percent

Recommendation: If you've got it, use it.




Test #4 A/C On, Windows Up vs. A/C Off, Windows Down

Result: Nice in theory; not true in practice

Cold Hard Facts: No measurable difference (unless you open the sunroof, too!)

Recommendation: Please, make yourself comfortable.




Test #5 Check Your Tire Pressure

Result: Important for safety and to reduce tire wear

Cold Hard Facts: No measurable effect on the vehicles we tested

Recommendation: Check your tire pressure often but don't expect a big savings.




Test #6 Avoid Excessive Idling

Result: More important than we assumed

Cold Hard Facts: Avoiding excessive idling can save up to 19 percent

Recommendation: Stopping longer than a minute? Shut 'er down.




The Tests

Our results are based on two separate fuel testing sessions. On each occasion we took two cars from the Edmunds.com long-term fleet and drove on a 56-mile test loop. Our route circled Owens Lake near Lone Pine, California, at the foot of Mount Whitney, the tallest mountain in the lower 48 states. We chose the route because it was so deserted we could vary our speed and driving style without interfering with the flow of traffic. The only other cars we saw on the route were a caravan of test vehicles from Mercedes-Benz. We drove the loops back-to-back to ensure that we were comparing similar wind and temperatures. We logged our results and later put them on a spreadsheet where the results were averaged.


Test #1: Aggressive vs. Moderate Driving

This is gonna hurt. Our tests showed that the most significant way to save gas is: you. And we're talking massive fuel economy gains. Think you need a hybrid? Chances are you've got hybrid-style mileage in your gas pedal foot. Don't mash the gas when you start up. Take the long view of the road and brake easy. This tip alone can save you unbelievable amounts of gas. If you slowed your 0-to-60-mph acceleration time down from your current 10 seconds to a more normal city pace of 15 seconds, you'll feel the savings immediately.

Method: We conducted this test four times. The first time we did the full 55-mile loop once by accelerating aggressively 15 times at 3/4-throttle from zero to a cruising speed of 75 mph. We also applied the brakes hard to come to a full stop. Then, we drove the second loop by accelerating moderately 15 times at 1/4-throttle to a cruising speed of 70 mph. We braked lightly to a full stop. In the second set of tests we drove 25 miles making 25 rapid accelerations to 65 mph at 3/4-throttle. After 1 minute of cruising we braked hard and repeated the cycle up to 65 mph. We then drove the same distance making 25 moderation accelerations to 60 mph at 1/4-throttle. After 1 minute of cruising we applied the brakes easily and came to a full stop.


Test #2 Lower Speeds Saves Gas

Remember a thing called the speed limit? On most highways it is either 65 or 70 mph. How fast are the cars and trucks around you going? From 75 mph to 90 mph. These people are wasting a lot of gas for the chance to get there a little earlier. Factor in safety concerns and a speeding ticket once or twice a year and going fast is a costly proposition.

Method: This test was simple. For 50 miles we drove with the cruise control set at 65 mph. Then, for another 50-mile stretch we drove with cruise set at 75 mph. We repeated this test going in the opposite direction. It is amazing how obvious the difference in gas mileage was. Just think what would have happened if we had slowed down to 60 mph. The only problem is with impatient drivers behind you. One driver became so irate that he tried to run our editor off the road. Still, if you are pinched by gas prices. Leave a little early and drive the speed limit (in the slow lane).


Test #3 Use Cruise Control

Using cruise control is a bit of gas-saving advice frequently on tips lists. We have always agreed with this tip in theory but we hadn't expected such significant results. First, it smoothes out the driver's accelerator input by preventing nervous "surging." Second, it makes the driver take the long view of the road rather than reacting to every change in the traffic around them.

Method: We did this test twice with four different cars each time driving the 55-mile loop. The first time we set cruise control to 70 mph. The second time, with the cruise control off, we varied our speed between 65 mph and 75 mph. We tried to mimic the driving style of a person who is in moderate freeway traffic.

One thing that's important to note: if you are in a mountainous area you should turn off cruise. It will try to keep you up to the speed you've set and will use a lot of extra gas downshifting to lower gears to accomplish this.


Test #4 A/C On, Windows Up vs. A/C Off, Windows Down

This has got to take you back to the days with the family on vacation. Dad says, "Turn the A/C off! It wastes gas!" And Mom says, "We can't roll the windows down or everyone on the highway will think we can't afford A/C." And you're in the back roasting, hoping someone will win the argument so you can cool off.

Well, family psychology aside, if dads are still saying this, they aren't necessarily right. While the A/C compressor does pull power from the engine wasting some gas, the effect appears to be fairly minimal in modern cars. And putting the windows down tends to increase drag on most cars, canceling out any measurable gain from turning the A/C off. But this one depends on the model you're driving. When we opened the sunroof in our SUV, the mileage did decrease even with the A/C off. Still, in our experience, it's not worth the argument because you won't save a lot of gas either way. So just do what's comfortable.

Method: We drove the full 55 mile-loop in two cars at equal speeds both times — 65 mph. The first loop we drove with the A/C on and the windows up. The second loop we drove with the A/C off and windows down. In the second test we drove 20-mile loops. This was far enough to see our gas mileage level off and remain steady on the computer trip meter.


Test #5: Check Your Tire Pressure

No matter how many times drivers hear about the importance of tire pressure, most of them don't do anything about it. They probably don't like squatting beside their car in a busy gas station with fumes swirling around them. But is it important? The answer is yes, for a number of reasons. Properly inflated tires are less likely to fail at high speeds. They wear more evenly and, yes, they deliver better gas mileage. How much? In this test we saw a modest difference in two of the cars. It might have been more dramatic with different tires on different cars. Experts swear by it; we couldn't really document it. And we wound up wondering if tire technology, like the design in other areas of the car, had improved.

Eventually, we concluded that each set of tires is different and every vehicle is different. We recommend that you do your own tests to see what inflation setting gives you the best fuel economy.

Method: We drove the 55-mile test loop four times at 60 mph — twice with tires at or above proper inflation. Once, we did the test with the tires 5 psi below the pressure recommended by the manufacturer. Since this produced very little difference we enlarged the gap and under inflated the tires by 8 psi. We felt that it was important to make sure the tires were inflated to the recommended level or above.


Test #6 Avoid Excessive Idling

If you turn off a light bulb as you leave the room you'll save electricity. If you turn off your car you will save gas. Obviously. But related questions are more difficult to answer. If you're only stopping for only a minute, is it better to shut off the engine or keep it idling? Should I shut off the engine in traffic? How much gas will this save? What rule of thumb do I use when trying to save gas this way?

Method: We took two cars and drove a 10-mile route stopping 10 times for two minutes. We shut down the car each time. Then we drove the same route at the same speed and let the car idle for two minutes.

Conclusions

The good news is that you can drastically improve your gas mileage. The caveat is that you have to change your driving habits. If you are willing to change, you'll find many related benefits too: no speeding tickets, greater safety, reduced stress and lower repair bills for tires and brake pads. In the long run this will save you money. And who knows? You might like the new you.

1. Check your air filter

A clean air filter is the key to good fuel economy. A dirty air filter restricts the flow of air into the engine, which harms performance and economy. Air filters are easy to check and change; remove the filter and hold it up to the sun. If you can't see light coming through it, you need a new one. Consider a K&N or similar "permanent" filter which is cleaned rather than changed; they are much less restrictive than throw-away paper filters, plus they're better for the environment.

2. Check your tire pressure

Next to the air filter, under-inflated tires are one of the most commonly ignored causes of crummy MPG. Buy a reliable tire gauge, check your tires when they are cold (driving the car warms up the tires and the air inside them, increasing the pressure), and keep them properly inflated. Use the inflation pressures shown in the owner's manual or on the data plate in the driver's door jamb.

3. Slow down

As speed increases, fuel economy decreases exponentially. If you one of the "ten-over on the freeway" set, try driving the speed limit for a few days. You'll save a lot of fuel and your journey won't take much longer. Just be sure you keep to the right, so you won't impede the less-enlightened.

4. Hang with the trucks

Ever notice how, in bad traffic jams, cars seem to constantly speed up and slow down, while trucks tend to roll along at the same leisurely pace? A constant speed keeps shifting to a minimum -- important to those who have to wrangle with those ten-speed truck transmissions -- but it also aids economy, as it takes much more fuel to get a vehicle moving than it does to keep it moving. Rolling with the big rigs saves fuel (and aggravation).

5. Accelerate with care

Jack-rabbit starts are an obvious fuel-waster - but that doesn't mean you should crawl away from every light. If you drive an automatic, accelerate moderately so the transmission can shift up into the higher gears. Stick-shifters should shift early to keep the revs down, but don't lug the engine -- downshift if you need to accelerate. Keep an eye well down the road for potential slowdowns. If you accelerate to speed then have to brake right away, that's wasted fuel.

6. Get back to nature

Consider shutting off the air conditioner, opening the windows and enjoying the breeze. It may be a tad warmer, but at lower speeds you'll save fuel. That said, at higher speeds the A/C may be more efficient than the wind resistance from open windows and sunroof. If I'm going someplace where arriving sweaty and smelly could be a problem, I bring an extra shirt and leave early so I'll have time for a quick change.

7. Back off the bling

New wheels and tires may look cool, and they can certainly improve handling. But if they are wider than the stock tires, chances are they'll create more rolling resistance and decrease fuel economy. If you upgrade your wheels and tires, keep the old ones. I have fancy sport rims and aggressive tires on my own car, but I keep the stock wheels with a good narrower-tread performance tire in the garage. For long road trips, the stock wheels give a smoother ride and better economy.

8. Clean out your car

The more weight your car has to haul, the more gas it needs to do the work. If you're the type who takes a leisurely attitude towards car cleanliness -- and I definitely fall into that group -- periodically go through your car and see what can be tossed out or brought into the house. It doesn't take much to acquire an extra 40 or 50 lbs. of stuff.

9. Out with the new, in with the old

Many people keep their old cars around even after they buy a new one. A spare car, especially if it's an econobox, can be good insurance against temporary spikes in gas prices due to world events. The costs of keeping the car may or may not be less then the fuel saved, but it does allow for more predictability in your budget. My old beater doesn't look like much, but it goes 10 miles further on a gallon of gas than our regular car. For that, I can afford to look bad!

10. Don't drive

Not a popular thing to say on a car site, I know, but the fact is that if you can avoid driving, you'll save gas. Take the train, carpool, and consolidate your shopping trips. Walking or biking is good for your wallet and your health. And before you get in your car, always ask yourself: "Is this trip really necessary?"

Some other good fuel saving links

http://www.ftc.gov/bcp/edu/pubs/consumer/autos/aut10.shtm

http://www.epa.gov/otaq/consumer/17-tips.pdf