Experts offer ways to keep gas costs from eating your budget

Deirdre Diaz typically drives home each year to California to visit her mother.<br><br>But this year, the Dallas stay-at-home mom and her family will spring for a plane ticket to bring her mother to Dallas.<br><br>The

Monday, July 10th 2000, 12:00 am

By: News On 6

Deirdre Diaz typically drives home each year to California to visit her mother.

But this year, the Dallas stay-at-home mom and her family will spring for a plane ticket to bring her mother to Dallas.

The reason: It would cost the Diaz family a fortune to fill up their sport-utility vehicle for the drive out West.

"It's like $60 now" to fill up her Chevy Suburban, Mrs. Diaz said. "That is just too much money to fill that vehicle up and head back. I'm just going to buy my mom a ticket."

Something economists call "user cost" is at the heart of consumers' efforts to beat soaring gas prices, said Kenneth B. Medlock III, an energy expert at the James A. Baker III Institute for Public Policy at Rice University in Houston.

"At low prices, we are less concerned about the cost of fuel because it is a smaller portion of our total auto expense," Mr. Medlock said. "However, when prices increase, we find ways to economize."

You can rant and rave and shake your fist at high gasoline prices, but that won't change the numbers. You would be better off taking some concrete action that really would save you money in fuel costs.

For instance, consolidate your trips and errands to cut down on driving time.

"Plan a schedule," said Matt Deas of Dallas, filling up his vehicle at a North Dallas gas station.

Mrs. Diaz, who pumped $20 worth of gas into her husband's BMW, does just that. She buys stamps and fills her prescriptions at the Albertson's supermarket where she buys groceries, "which really helps," she said.

"I'm so short on time, and I can't afford to really waste money," Mrs. Diaz said.

She also carpools with another mom.

"Carpooling is a simple way to cut your bill in half and make a few friends in the process," said Allen Mesch, director of the Maguire Energy Institute at Southern Methodist University in Dallas.

Buy smarter

Another way to save money is to change your buying habits when it comes to gasoline.

"Fill it up at three-quarters, if possible," Mr. Deas said. "I don't let it get under a half."

That trick will save money per visit, but it won't save money overall. The best way to save once you're at the pump is to purchase the lowest grade of gasoline.

"Many consumers buy premium gasoline with the assumption that higher costs translate into better performance and improved fuel economy," Mr. Mesch said. "For most motorists, buying a higher-grade gasoline is simply throwing money down the drain."

Buying premium gas to avoid knocking or pinging in a vehicle's engine is "largely unwarranted unless you have a high-performance sports car," he said.

You also can hunt for a better price.

"The cut-rate stations can offer savings ranging from 10 to 15 cents per gallon," Mr. Mesch said. "All gasoline sold must meet federal quality specifications, and the gasoline you buy at RaceTrac was probably produced at an Exxon refinery anyway. The major difference between gasoline brands is the additive packages, but there is very little difference between them."

But it's more than buying the right type of gasoline at the best price. You won't save money if you don't keep your vehicle in good condition. Let's start with the tires. Don't let them get underinflated, because that will cause the vehicle to eat more gas.

"The majority of the cars on the road today have underinflated tires, and if they would inflate them to the recommended pressure, they will improve their fuel economy significantly," said Bob Woods, professor of mechanical engineering at the University of Texas at Arlington.

"That's the biggest thing you can do," he said. "If they're underinflated, it causes more rolling resistance and takes more power to run your car."

"Studies have shown that it's not uncommon for vehicles to have 6 percent increased fuel consumption because of underinflated tires," said Chris Horn, vice president of consumer affairs at the Specialty Equipment Market Association in Diamond Bar, Calif., which represents the specialty automotive aftermarket industry. "Maintaining proper tire pressure can get you up to 20 more miles from a tank of gas."

There are several places you can look to find out the maximum recommended tire pressure for your car. Car manufacturers must place a label in the car stating the correct tire pressure. This label may be found on the edge of the door, the doorjamb, in the glove compartment or on the inside of the gas-cap cover. If the label lists a pounds-per-square-inch or psi range, go by the higher number in order to maximize your fuel efficiency.

Radial tires can be underinflated and still look normal, according to www.fueleconomy.gov, a Web site put together by the U.S. Department of Energy and the Environmental Protection Agency.

What could also make tires appear underinflated is too much weight on the vehicle. Got those golf clubs in the trunk? Get them out of there. Ridding your car or truck of unnecessary excess weight will reduce your fuel costs.

"The more mass, the more force it takes to accelerate, and force costs gas mileage," said Frank Markus, technical director of Car and Driver magazine.

Also, be sure your wheels are properly aligned and your brakes are properly adjusted to minimize rolling resistance. Brakes play a key role in your driving style, which you must change if you want to use less gasoline.

"Nobody wants to hear it, but accelerate slowly and try not to use your brakes" too much when stopping, Mr. Markus said. "If you see a traffic light coming up, let your foot off easy and coast down."

"Don't drive up to it and then use the brakes," Mr. Woods said. "It's driving the car 40 miles an hour longer than it needs to be driven."

Change your driving habits

Also, you can avoid jackrabbit starts.

"Smooth acceleration reduces gasoline consumption and lowers pollution," Mr. Mesch said.

On hot days, after you reach speeds of 45 mph and beyond, it's more fuel-efficient to run the air conditioner and shut your windows than it is to have your air conditioner off and your windows rolled down, Mr. Markus said. At higher speeds, open windows create wind resistance that's more of a drag on your engine than the air conditioner is. Or if you can tolerate it, just open the vent.

In highway driving, more than 50 percent of the energy required to move your car down the road goes to overcoming aerodynamic drag, or pushing air out of the way, experts said.

If you own a pickup, you can reduce drag by putting the tailgate down and covering the bed, automotive experts said.

Use your overdrive gears, which improve fuel economy during highway driving. When you use overdrive, your car's engine speed decreases, which reduces fuel consumption and engine wear.

Pamela Yip covers personal finance for The Dallas Morning News. If you have a story idea, e-mail her at pyip@dallasnews.com.

Stretch your fuel dollar

Here are some ways to get the biggest bang from your gasoline dollar:

Bunch up errands so you won't have to make as many trips.

Keep tires properly inflated.

Avoid unnecessary idling of your engine.

Coast up to red lights rather than accelerating and then stopping quickly.

Get rid of excess weight in the car.

Check and replace air filters regularly.

Change your motor oil regularly. Some oils contain additives that reduce friction and may increase a vehicle's fuel economy by 3 percent or more.

Keep your engine tuned.

SOURCE: Dallas Morning News research.