Last Updated Mar 8, 2011 2:28 PM EST
Experts caution, however, that while high-mileage hybrids and diesels will reduce the amount you pay at the pump, they may not really save you money. "Consumers often make long-term decisions, like buying a vehicle, based on short-term information, like today's fuel prices," says Jack Nerad, executive editorial director and market analyst for kbb.com.
Rival automotive site Edmunds.com points out that with a few exceptions, hybrids and diesels remain much more costly than comparable gas-only models. "Hybrid technology hasn't been streamlined in a way that can bring costs down," says Ronald Montoya, consumer advice associate at Edmunds. "And the hybrid or diesel version of a car is often positioned as the high-tech model and thus is loaded with options not found in the gasoline equivalent." He notes further that federal tax credits for buying hybrids and diesels expired at the end of last year (although they still apply to plug-in electrics such as the Nissan Leaf and Chevrolet Volt).
While you may be motivated to buy a hybrid by more than just the bottom line, it's worth calculating the "payback time," the point at which your savings on gas will exceed the extra bucks you fork over for a more fuel-efficient car. Examples of hybrid and diesel models that don't make pure economic sense: Edmunds says the Nissan Altima Hybrid, with a list price of $26,800 has a payback time from extra mileage over the gas Altima of 10.3 years, longer than most people would own the car. And the $51,800 diesel BMW X5 xDrive35d has a payback time even longer than its name -- 25.2 years.
Whatever your motivations, here are two hybrids and two diesels that boast favorable cost comparisons with their gasoline alternatives.
Toyota Prius This iconic hybrid and EPA mileage champ (51 mpg in city driving, 48 highway), starting at an MSRP of $23,050, costs just $620 more than a gasoline Toyota Camry. Thus the payback time is only about eight months. Reviewers note that while Prius is no star at acceleration or sporty handling, it has an unmatched combination of passenger and cargo space, high mileage and affordability.
Lincoln MKZ Hybrid Ford Motor Co. took the surprising step of pricing this Lincoln hybrid sedan the same as the gasoline version at $34,605. So instead of worrying about payback periods, Lincoln buyers have to choose power or mileage. The 3.5-liter 263-horsepower gasoline V-6 is rated at 18 mpg in city driving, 27 highway. But the gas-electric hybrid power plant, with 191 horsepower, is rated at 41 mpg city, 36 highway. Of course if you are a hybrid buyer who doesn't care about the Lincoln name and some of its luxury touches, you can get essentially the same vehicle in the Ford Fusion Hybrid starting at $28,340 with less standard equipment.
Cost comparisons with diesels have an added complication: diesel fuel is often more expensive than gasoline. In the most recent AAA report, diesel cost 37 cents more than regular gas but only 11 cents more than premium, which is recommended for the gas versions of the two diesels below.
Mercedes-Benz GL-Class Diesel Mercedes-Benz priced this diesel GL 350 Blue Tec starting at $61,950 or about $1,000 lower than the gas version, the GL 450 4Matic. Reviewers say this car-based utility (rated at 17 mpg city, 23 highway vs. 13/17 for the gas model) has among the most comfortable rides and best maneuverability in this luxury class. But start adding options typical in luxury SUVs like leather seats, navigation and satellite radio and the sticker soon tops $70,000. If you are in this price league, you won't worry too much about the extra cost of diesel fuel.
Audi A3 Diesel This stylish hatchback wagon, at $29,950, costs $1,432 more than its gas version. But with its rating of 30 mpg in city driving, 42 mpg on the highway, Edmunds calculates it will pay back the difference in 2.3 years. The A3 is praised by reviewers for its fun performance, top safety rating and sporty exterior styling. In a recent listing of greenest cars, the diesel A3 got an honorable mention. (Diesels rarely top this list, from the American Council for an Energy Efficient Economy, because of their emissions of smog-causing nitrogen oxides. But the A3 diesel is rated the most efficient small wagon by the EPA).
Of course, no matter how painful those filling station stops are, you still might just keep your old car if it is in good running order. To do a cost/benefit analysis of keeping your old car vs. getting a new one, check out Edmunds' gas guzzler calculator.
Photos courtesy of the manufacturers
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