8 Ways to Maximize Gas Mileage

Kelli B. Grant describes 8 Ways to Maximize Gas Mileage on the site http://www.smartmoney.com.


Americans drive more during the summer than during the rest of the year because of summer vacations and road trips during the three seasonal holiday weekends, says Christie Hyde, a spokeswoman for AAA. More people than usual are hitting the road this year, according to AAA. Memorial Day traffic was up 5.8%, and Fourth of July traffic 17.7%, for a total of 28 million and 31.4 million people on the road, respectively.

Gas prices have held steady this summer, with national averages in the neighborhood of $2.70 per gallon. But driving a vehicle that isn’t at its most fuel efficient can cost the driver the equivalent of an extra $2 or more per gallon, according to FuelEconomy.gov.
There’s no single automotive fix to dramatically improve fuel efficiency, says Jim Kliesch, a senior engineer at the Union of Concerned Scientists. But a few tricks used collectively can lower the cost of filling a gas tank by as much as 50%, he says.

Pack light

Clearing out the junk from a trunk can offer some quick savings. Every 100 pounds of added weight in the back of a car can reduce its fuel economy by as much as 2%, according to the U.S. Department of Energy. Hauling a cargo carrier, skis, kayaks or other gear atop the car is more taxing and can lower a car’s fuel economy by about 5%. “There’s going to be air resistance,” says Karl Brauer, a senior analyst for Edmunds.com.

Swap vehicles
Consumers with multiple vehicles should drive the more fuel-efficient one whenever possible. The difference in miles per gallon is especially obvious on long trips.

Keep up with maintenance

Following the car’s recommended maintenance schedule can help keep it operating at maximum efficiency. An engine in need of a tune-up operates about 4% less efficiently, according to the DOE. Drivers who have followed the schedule and don’t see the phrase “service required” or “check engine” on their dashboard are probably in good shape, Brauer says.

Check the tires

A spring tire pressure survey from the Rubber Manufacturers Association found that only 17% of vehicles had all four of their tires properly inflated. Under- or over-inflated tires change the way the car handles, adding drag and speeding wear, which can reduce fuel efficiency by about 3%. When inflating, don’t go by the figure stamped on the tire -- that’s the maximum it can handle, Hyde says. Look to the driver's side door panel or owner's manual for information on proper inflation levels.

Use the right motor oil

Check the driver’s manual for the proper grade, Kliesch says. Using the wrong one can lower fuel efficiency by 1% to 2%.

Create a fuel-efficient route

Plot out errands for the shortest route possible around town, Brauer says. On longer trips, try to factor in weather, construction and traffic to avoid periods when the car is idling -- which gets you zero miles per gallon. Many GPS units offer alternate route plotting; Google Maps also shows traffic conditions.

Drive responsibly

The government estimates that the most fuel efficient driving speed is between 40 and 60 miles per hour for most vehicles. Drivers who begin following the speed limit should see dramatic improvements in fuel economy, Kliesch says. Speeding and rapid acceleration and braking can collectively reduce fuel efficiency by up to 33% at highway speeds and by about 5% at slower, local speed limits, according to the Alliance to Save Energy. When possible, set the cruise control for steadier speeds.

Skip premium fuel

Aside from high-end sports cars that list premium fuel as a requirement in their owner's manuals, most cars will do fine on regular unleaded. The national average price for a gallon of unleaded is currently $2.72; a gallon of premium, $2.99, according to AAA. The difference amounts to roughly $5 per average tank.