With oil prices reaching multiyear highs due to reduced oil production in OPEC countries, Russia, and elsewhere, U.S. motorists could be facing significantly higher gas prices this summer, says Patrick DeHaan, senior petroleum analyst at GasBuddy, a website and smartphone app that helps drivers find the best deals.

Motorists in some areas are already seeing gas prices of $3 or more, and that could rise further, at least in the short term, says DeHaan.

AAA reported today that the average price for regular-grade gasoline is now $2.81 per gallon compared with $2.37 a year ago.

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Overall, DeHaan predicts that drivers could, on average, shell out an additional $100 to $200 for gasoline in 2018 compared with last year

The amount you'll pay depends, of course, on the gas station where you fill up. And the differences can be significant, says DeHaan. For instance, in Long Beach, Calif., he says there’s a Mobil station charging $3.79 per gallon for regular gas. But nearby, there’s a United Oil station charging $3.33 for the same thing. That’s a difference of 46 cents per gallon.

Fill up that minivan at the wrong station and you'll end up paying about $9 more than necessary.

And there are drivers who unnecessarily buy higher-cost premium gasoline for cars designed for regular fuel, according to a study by AAA. Based on current national average gasoline prices, mid-grade gasoline costs nearly 28 cents a gallon more than what you'd pay for regular.

Premium gas costs 52 cents more, according to the AAA, but DeHaan says that in areas like Chicago you may find premium $1.20 per gallon more than regular.

So if your car can operate on regular but you opt for mid-grade or premium gas, you could be paying $5 to $10 more to fill that same minivan's tank.

Tips to Spend Less on Gas

"If you're just looking at the price from the street, you're leaving money on the table," says DeHaan. There are things you can do to keep your gas expenses down. Among them:

Use a gas station app or website.  Smartphone apps, such as those from GasBuddy, AAA, Fuel Finder, and Gas Guru, are particularly convenient when you're traveling and away from your computer. They’re available for Android and iOS devices. Many are free. (The Android version of Fuel Finder costs $1.99.) You can filter results by fuel grade and sort by distance and price, as well as get GPS-guided directions to the station you choose.

GasBuddy and Fuel Finder also let you check stations for amenities such as ATMs, restaurants, and car washes. GasBuddy has station reviews, which might tell you, for instance, which restrooms to avoid. And Gas Guru lets you save your favorite stations, so you can remember where to stop on your way back.

The Google Maps and Waze apps, which many people use for real-time traffic alerts and driving directions, also offer gas-price info.

You'll likely find that to get a better deal at stations that are not located on major highways, says Michael Calkins, a manager at AAA. Of course, making a big detour to pay less may not make sense.

Calkins also says to make sure that when you compare prices you consider buying only top-tier detergent gasoline, which is better for your car. 

Check the prices in the different states you'll visit. Prices can vary significantly between states, often because of differences in state gas taxes. DeHaan found gas prices to be around 30 to 40 cents a gallon cheaper on Interstate 90, on the Ohio side of the border with Pennsylvania.

Think about how best to pay. Some stations offer a lower price if you pay with cash instead of a credit card. The difference between the cash and credit price usually ranges from around 10 to 15 cents a gallon, says DeHaan, though he says it can be as much as a dollar.

Another option is to pay with a cash-back credit card. While the credit card price may be higher than the cash price, the reward you receive could make using the credit card a better deal.

It's worth noting that a rewards credit card could even provide greater savings than a gas credit card from a big oil company (such as Texaco or Chevron), says DeHaan. For instance, the Bank of America Cash Rewards Visa card offers 3 percent cash back on gasoline purchases, among other things, up to $2,500. The Sunoco Rewards Credit Card, by contrast, offers only a flat 5 cents per gallon discount, though there is no limit on how much you can spend.

And if you plan to pay by debit card, don't assume that you are getting the cash price. Some stations could actually charge you the credit card rate instead. Check the posted prices at the pump. Selecting the debit option and entering a pin when you pump your gas is often a good indication your transaction will be handled as cash, says Lyle Beckwith, senior vice president of the National Association of Convenience Stores, based in Alexandria, Va.

Regular Gas vs. Premium Gas

Think expensive gas means increased power and better fuel economy? On the 'Consumer 101' TV show, Consumer Reports expert Mike Monticello reveals to host Jack Rico what to know before filling up at the pump.