Check Your Tire Pressure
This is often over looked or put often since it is inconvenient. Under inflated tires are not only a driving hazard, but they burn more gas. Keeping your tires properly inflated is an easy way to improve your gas mileage. Look in your owners' manual and see what the recommended tire pressures are. Add two pounds to that number. This will keep the tires properly inflated when the tires are operating in cooler weather and road conditions.
Higher Speeds Burn More Gasoline
Exceeding 40 mph forces your auto to overcome tremendous wind resistance. Traveling at 55 mph gives you up to 21% better mileage when compared to speeds of 65 mph and 70 mph. The 55 mile per hour speed limit set a few years back is still the most efficient speed for most vehicles. Driving 65 mph instead of 75 mph will increase your gasoline economy by about 10 percent.
Clean Out Your Trunk and Back Seat
Remove excess weight from trunk and inside of the car. The extra weight you are carrying for various reasons is just reducing your gas mileage, especially when driving up inclines. Cleaning out will come back to you as extra miles per tank full. An extra 100 pounds in your trunk reduces gasoline economy by about 1 percent.
Turn Off The Air Conditioner
A/C takes about 8 horsepower to run and that uses more gas. At low speeds and stop and go traffic, it costs less to drive with the windows down, but on the highway, using an air conditioner is cheaper. On a long trip on the open highway, it is better to use the A/C than to drive with the windows open. The extra drag of open windows on a vehicle can eat up more gasoline than the A/C. Air conditioning is a super drain on your engine's efficiency, so turn it off when you can. If you're within few minutes of your destination, turn off the air conditioner but let the fan continue to circulate the cold air in the car.
Anticipate Stops and Start Back Up Slowly.
Think ahead to anticipate stops so your vehicle can coast down. Utilize your cars forward coasting motion to your benefit. Accelerating hard and braking hard wastes gas, increases pollution, and wears out your brakes. Take off slowly from a full stop. Do not accelerate fast from a stop light! Accelerate easy to your cruising speed and maintain it. Use your cruise control if you have it to maintain a steady speed. Slow down a bit when you drive, the faster you go, the more gasoline you use. When you go somewhere, leave 10 or 15 minutes earlier so you can go easy and save some gasoline.
Avoid Idling Your Car
If you are going to be stopped for more than one minute, you will save gas by turning your vehicle off and restarting it when you are ready to go. Stuck in traffic? Don't sit and idle. Avoid the drive thru when you go to the bank, park your car and go inside instead of wasting gasoline waiting in line. Do the same when you go to Burger King and McDonalds.
Keep Your Engine Tuned Up
If you keep your engine well tuned, it is good way to stretch your gas dollar. An engine that grinds for ten seconds before firing up wastes gas. New spark plugs and a new air filter are very important for complete combustion. Replacing clogged filters can increase gas mileage up to ten percent. Tuning your engine according to your owner's manual can increase gas mileage by an average of four percent. Increases vary depending on a car's condition.
Consolidate Your Errands to Make One Trip
Try to combine your errands so that you can get everything you need during one trip. Park in the first spot you find. If you wander all over the parking lot looking for that really close parking space, you'll use more gas.
Don't Fill Your Tank Until Near Empty
If you do this, it can extend your gasoline mileage because you are hauling a lighter load as the tank nears empty. You will be going more miles with less weight. Do not run out of gas if you take this to the extreme.
Check For Good Aerodynamics
Loaded car racks increase wind resistance and reduce mileage so use them sparingly or at a last resort. Install a bed cover on your truck to make it more aerodynamic. Air rushes over the cover and off the back of the truck, instead of into the bed, where it pushes on the tailgate and creates drag.
Try To Drive Less
Give your car a rest by car pooling, taking public transportation, riding a bike or walking. The exercise will do you good if you can work it in. It's not always possible, but carpooling saves you a lot of dollars in fuel bills when shared with the participants.
Change Your Oil
Change your oil. According to the U.S. Department of Energy (DOE) and Environmental Protection Agency (EPA), you can improve your gas mileage by using the manufacturer's recommended grade of motor oil. Motor oil that says "Energy Conserving" on the performance symbol of the American Petroleum Institute contains friction-reducing additives that can improve fuel economy.
Check and replace air filters regularly. Replacing clogged filters can increase gas mileage up to ten percent.
Check Out Claims About "Gas-Saving" Gadgets
Be skeptical of claims for devices that will "boost your mileage by an extra 6 miles per gallon," "improve your fuel economy up to 26 percent," or the like. EPA has tested over 100 supposed gas-saving devices ? including mixture "enhancers" and fuel line magnets ? and found that very few provide any fuel economy benefits. The devices that work provide only marginal improvements. Some "gas-saving" devices may damage a car's engine or increase exhaust emissions. For more information and a full list of tested products, check www.epa.gov/otaq/consumer.htm
Consider the Alternative Fuel Vehicles
Alternative Fuel Vehicles (AFVs) operate on alternative fuels, such as methanol, ethanol, compressed natural gas, liquefied petroleum gas, electricity, and others designated by the DOE. Using these alternative fuels in vehicles may reduce harmful pollutants and exhaust emissions. FTC Rules require labels on all new AFVs to give the vehicle's estimated cruising range and general descriptive information. Find out how many miles a new AFV travels on a tank or supply of fuel because, gallon for gallon, some don't travel as far as gasoline - powered vehicles.

Hybrid Electric Vehicles offer another option for car buyers. According to DOE and EPA, these vehicles combine the benefits of gasoline engines and electric motors and can be configured to achieve different objectives, such as improved fuel economy and increased power.

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