Remember the predictions about summer gas prices? Prices were going to be low – the lowest in years! – experts said. Supply would be plentiful. Refineries would churn fuel without the plague of problems.

You, the consumer, thought it was the perfect time to plan that cross-country road trip, maybe rent an RV for a week or two, and not break the bank on the fuel costs.

That was three short months ago. 

Today, gas prices have soared an average of 18 cents per gallon over the past nine days. Gas prices have spiked at their fastest rate since February. Our national average of $3.61 per gallon is actually 22 cents higher than it was on the same day last summer, according to AAA, whose experts spent Wednesday on Capitol Hill, testifying about $3 per gallon as being a "thing of the past."

You, the consumer, have a few choices. You could cancel your summer road trip, but that's demoralizing. Range anxiety might scuttle your idea of a long road trip with a pure electric car. So here’s what we propose:

Check out our list of the most fuel-efficient cars you could bring on your summer road trip. We'll also show you the cars you should avoid. It's our summer road-trip edition of fuel sippers versus gas guzzlers.

Sticker Price: $92,000
Invoice Price: $85,470
Fuel Economy: 12 mpg City, 17 mpg Highway

You'll pay a premium at the dealership for this exquisite vehicle, and then you'll pay a premium at the pump to actually drive it anywhere.

Research the BMW X6 M
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Sticker Price: $63,745 - $83,070
Invoice Price: $59,602 - $77,670
Fuel Economy: 14 mpg City, 18 mpg Highway

Scrutinize which trim level you're buying. Some of the higher-priced Escalade trim levels actually get even worse gas mileage.

Research the Cadillac Escalade
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Sticker Price: $45,480 - $52,065
Invoice Price: $42,296 - $48,420
Fuel Economy: 10 mpg City, 16 mpg Highway

The Suburban is a terrific vehicle for hauling people and towing stuff. It fits eight and has a towing capacity of 9,600 pounds. You're just going to pay a high price at the pump for all that cargo.

Research the Chevrolet Suburban 2500
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Sticker Price: $22,395 - $30,895
Invoice Price: $21,828 - $29,115
Fuel Economy: 17 mpg City, 21 mpg Highway

The Wrangler is a terrific summer car, in that you can take the top off, go off-roading. But you might want to take an extra gas can along.

Research the Jeep Wrangler
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Sticker Price: $36,890 - $52,360
Invoice Price: $33,588 - $47,653
Fuel Economy: 13 mpg City, 19 mpg Highway

The Armada has power and size, and it takes a lot of fuel to keep its curb weight of 5,561 pounds rolling down the highway.

Research the Nissan Armada
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Sticker Price: $39,145
Invoice Price: $37,579
Fuel Economy: 101 mpg City, 93 mpg Highway

The Volt is one of our favorite cars here at AOL Autos. Road-trippers will enjoy the miles provided by the electric charge, and the conventional gasoline engine that can continue the journey.

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Sticker price: $24,885
Invoice Price: $23,890
Fuel Economy: 27 mpg City, 46 mpg Highway

We've experienced diesels from European carmakers. Now comes one from a full-blooded American company targeted at mainstream consumers. Bottom line: You'll pay a little more at the pump for diesel fuel, but it will last you a whole lot longer. Ultimately, a terrific value.  

Research the Chevrolet Cruze Diesel
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Sticker Price: $24,200 - $30,005
Invoice Price: $22,748 - $27,930
Fuel Economy: 51 mpg City, 48 mpg Highway

The granddaddy of the hybrid car, Toyota has been a green-technology leader in the auto industry. The hybrid tech has been proven reliable over a decade on the road. It’s hard to think you’d go wrong purchasing this car.

Research the Toyota Prius
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Sticker Price: $25,200
Invoice Price: $24,192
Fuel Economy: 30 mpg City, 42 mpg Highway

Want to drive a fuel-sipping vehicle that has some sporty features and is actually fun to drive? The Golf TDI is for you. Diesel fuel packs more power, giving this car some punch and the ability to stretch a tank of gas.

Research the Volkswagen Golf TDI
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Sticker Price: $32,950
Invoice Price: $30,726
Fuel Economy: 108 mpg City, 92 mpg Highway

This plug-in hybrid uses Ford’s powersplit technology to significantly improve fuel economy over similarly sized vehicles using conventional powertrains.

Research the Ford C-Max Energi
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