Find Cheaper Gas Faster

As gas prices dip more than 60 cents below their August highs, drivers looking for bargain gasoline may notice that prices are falling faster at some stations than at others. In past years, cross-town prices often rose and fell in lockstep -- differing only by only a penny or two. But today, the shaky international oil market is shaking up prices in many neighborhoods, widening the spread between the highest and lowest prices. In your metro area now, you might save between 10 and 50 cents a gallon by visiting a new gas station. What's more, during this unusual period of market uncertainty, one gasoline station may have the lowest price today, while another station may have the lowest price tomorrow. To find stations with cheap gas, visit one of a few free Web sites that let you search prices by your zip code or state: Gasbuddy.com, GasPriceWatch.com and MSN Autos Local Gas Prices page.

For example, within a one mile stretch of Miami Beach, Fla., regular gas was recently as low as $2.53 a gallon and as high as $2.99 a gallon, according to GasPriceWatch.com. That's a savings of $9 for a minivan fill-up.

Prices are wild in other cities, too. During a recent 12-hour period, San Francisco had a 54-cent city-wide gas price difference, while Seattle had a 23-cent difference and Chicago had a 14-cent difference. So checking prices online may have a lasting payoff. Says Edgar Dworsky, founder of the advocacy Web site ConsumerWorld.org: "It's foolish -- or 'fuel-ish', if you will -- to drive around looking for the lowest price when you can use online sites to check fuel prices at area stations instead."

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This fall, the best time to check these Web sites is on weekdays -- when gas station attendants frequently get out their extension poles and change the prices on their marquees. "Gas prices are today reacting to changes in the gasoline futures market," says Brad Proctor, founder of GasPriceWatch.com. "During the week, prices jump up and down with the market. But the markets are closed on the weekends, so Friday's prices usually stay steady or drop slightly during the weekend."

We know you probably won't want to check prices online before each and every pit stop you make for the rest of your life. But during this unusual time for gas prices, you may find it profitable to pump these Web sites for information regularly. These sites even allow you to plot on a map where the cheapest gas prices are.

Top Web sites for gas prices

GasPriceWatch.com. Type in any zip code at this site and get current prices from all the gas stations within a 20-mile radius. The Dayton, Ohio, company says price-monitoring volunteers offer about 410,000 updates on prices each week. Our favorite feature is the electronic tickertape on the site's home page that lists price changes in the gasoline and crude oil futures markets. If prices for these indexes have dropped on a particular day, consider delaying your next pit stop for a day or two until that price drop has trickled down to local pump prices. But if futures market prices have spiked, fill your car up soon before pump prices likely follow suit.

GasBuddy.com. This site is the granddaddy of 178 Web sites, such as OrlandoGasPrices.com, that allow consumers to share reports on local gas prices. Find your neighborhood's gas-price information by going to GasBuddy and keying in your zip code. You'll be directed to the appropriate Web site that lists current prices. Jason Toews, a co-founder of this Brooklyn Park, Minn., company, says that volunteers add fresh prices on about 80,000 stations daily. The site even lists historical price data by state.

MSN Autos Local Gas Prices. This site reports gas prices in 252 markets offered by 90,000 or more gas stations a day, depending on the day. The data comes from credit-card transactions, data feeds on price changes from some gas station chains and surveys of gas station owners, and is supplied by the Oil Price Information Service (OPIS). This data is more thorough and reliable than the data provided by volunteer spotters at the other two sites, but the data tends to be 24 hours out of date, while the other sites refresh constantly as volunteer spotters supply information.

Three more tips to save on gas

Get carded. Apply for a credit card that refunds 5% of all gas purchases. Kiplinger's Personal Finance magazine's pick for the best gasoline reward credit card is BP Visa (877-278-4729), which gives you a 5% rebate on all BP purchases, including car washes and items at BP convenience stores. In addition, you get 2% back on most travel and dining purchases and 1% on the rest of your spending. To find other gas rewards cards, go to Credit Card Guide.

Budget your road trip online. Before you take your next long drive, consider estimating your trip's fuel costs by using AAA's Fuel Cost Calculator. Estimate how much fuel your next road trip will slurp up, given today's average prices. Then you'll have a better sense of judging whether driving is the best transportation option for reaching your destination -- particularly handy for long-distance moves.

Choose "regular" gas. Regular gas is recommended for two out of three cars. Check your car's manual to see if premium gasoline is recommended instead. If the manual says regular gas will do fine, you're wasting your money if you continue to use high-octane fuel. In fact, because it's harder to ignite, the higher-octane gas could make your car harder to start and cause it to run less smoothly, especially in cold weather.