Earlier this month, we told you about the prospects of gasoline reaching $4 a gallon this summer, and perhaps even as high as $4.60 in major metropolitan areas. A couple weeks ago, the AAA Daily Fuel Gauge Report listed the national average price for a gallon of regular gasoline at $3.48. The average price today is $3.64 a gallon. While no analyst is certain how high the price will climb, the $4 threshold is quickly approaching.

In Michigan, for example, some experts say the $4 threshold could come much sooner. “For Michigan, we could see $4 in a matter of just a month,” said Patrick DeHaan, senior petroleum analyst for GasBuddy.com, in an interview with the Detroit Free Press. DeHaan said that he has seen quick spikes in the price of gas, and believes that Michigan may be within 20 cents of the $4 mark as early as next week.

If you’re in the market for a new car and are concerned with rising gas prices, shopping for a hybrid, like the Toyota Prius, is the obvious choice. Extended-range and electric vehicles, like the Nissan Leaf and Chevrolet Volt, are also good at minimizing, if not eliminating the need altogether, to stop at a gas station. But you’re not limited to those choices. Many cars have trims specifically designed to enhance fuel economy.

The 2012 Buick LaCrosse now comes standard with a fuel economy-enhancing technology called eAssist, which adds a small battery and electric motor. With this mild hybrid powertrain, the LaCrosse eAssist achieves EPA fuel economy estimates of 25/36 mpg city/highway, and costs about $30,200. In comparison, the V6 LaCrosse gets 17/27 mpg and costs about $500 more than the eAssist model.

Another good option is the 2012 Lincoln MKZ Hybrid, which is the same price as the gas-only MKZ. The MKZ Hybrid, which gets an EPA estimated 41/36 mpg city/highway, will save you more than $1,100 in annual fuel costs over the gas-only variant, and since you’re not paying extra for the hybrid version, you’ll realize money savings immediately. The MKZ gets 18/27 mpg city/highway, while the hybrid model gets 41/36.

Diesel models are also a good fuel-efficient alternative. The 2012 Volkswagen Jetta TDI starts at $22,775. Its diesel engine helps it achieve 30/42 mpg city/highway, and it will save you about $200 a year in fuel costs compared with the base gasoline version.

Another option is the 2012 Chevrolet Cruze Eco. Starting at $19,325, the Cruze Eco gets up to 28/42 mpg city/highway. The Eco model costs about $2,500 more than the base model, but will save you $225 in annual fuel costs.

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