Toyota PriusClick to enlarge picture

One of the first hybrids available in America, the Toyota Prius tops the list of most fuel-efficient vehicles of the 2008 model year.

Each year the U.S. Environmental Protection Agency (EPA) publishes fuel economy estimates for most new passenger vehicles sold in the U.S. Vehicles that have a gross vehicle weight above 8,500 lbs. are excluded.

This annual ranking of new model lines—according to EPA fuel economy data for combined city and highway driving—shows five gasoline-electric hybrid vehicles at the top of the 2008 model year list—more than ever before.

For consumers comparing fuel economy numbers, it will quickly become evident that the ratings for the 2008 models seem considerably lower than 2007. This is because the EPA has updated its methods of computing fuel economy based on faster driving, stronger acceleration, air-conditioning use and operation in colder temperatures. Read more about how the EPA is changing its fuel economy ratings

There have been many complaints—especially from hybrid owners—that in real-world driving situations, their vehicles could never achieve the lofty numbers reported by the EPA. The adjustment for 2008 should help to make the numbers more realistic.

Photo Gallery: Top 10 Fuel Misers

Not surprisingly, the new ratings seem to have affected the hybrids the most, but they still remain at the top of the fuel economy ladder.

The Toyota Prius continues to lead the pack, followed by the Honda Civic Hybrid, Toyota Camry Hybrid and the Nissan Altima Hybrid.

The five-seat Toyota Prius, which was redesigned as a midsize sedan for the 2004 model year, is now rated at 48 mpg in the city and 45 mpg on the highway, putting it in the top position on the list. Prius combines the power of a 1.5-liter 4-cylinder gas engine and an electric motor to produce a total of 110 horsepower. A continuously variable transmission (CVT) is standard—a manual is not offered.

Most of the vehicles with the ten best fuel economy ratings are small cars, but there are some larger car options. The Camry Hybrid is a midsize sedan with a roomy interior and a gas-electric hybrid system that produces a V6-like 187 horsepower while rated at a combined 35 mpg by the EPA.

The other exception to the small car trend is the Ford Escape Hybrid and its Mercury Mariner Hybrid and Mazda Tribute Hybrid siblings. This trio of SUVs each achieves an impressive combined 32 mpg, while the AWD versions still do well at 28 mpg combined.

While hybrids do achieve impressive fuel economy, there is a premium to be paid in order to purchase one. For example, the Honda Civic, rated at a combined 29 mpg cannot match the 42 mpg that the Civic Hybrid should achieve; however, it is also priced about $7,000 less.

The top-ranked non-hybrid vehicle for 2008 is the Toyota Yaris. Rated at a combined 32 mpg, the Yaris provides a roomy, versatile interior in a rather inexpensive package. The Honda Fit provides a similar offering while rated just slightly lower at 31 mpg combined.

No pickup trucks, vans, luxury cars or large sedans rank in the top ten, and the Ford Escape Hybrid and Mercury Mariner Hybrid are the only vehicles from U.S.-based automakers in the top ten.

Unlike previous years, there are no models with diesel engines on the list of top ten fuel misers for 2008. The reason: diesel fuel has changed in the U.S. to an Ultra-Low Sulfur Diesel (ULSD). Most of the diesel vehicles that had been on this list (Volkswagen Jetta TDI, New Beetle TDI, and Golf TDI) are being re-engineered to work with this new fuel, and are on a sales hiatus stateside.

The new Volkswagen diesels are due early next year, with fuel economy numbers expected above 50 mpg. In the coming year, a number of new diesel models should arrive that can run cleaner and more efficiently thanks to this new fuel.

Here are the top 10 fuel-efficient vehicles for 2008, based on EPA fuel economy data for combined city and highway driving:

1.Toyota Prius 48/45/46 mpg
2.Honda Civic Hybrid 40/45/42 mpg
3.Nissan Altima Hybrid 35/33/34 mpg
4.Toyota Camry Hybrid 33/34/34 mpg
5.Ford Escape Hybrid 2WD (tie)
Mercury Mariner Hybrid 2WD (tie)
Mazda Tribute Hybrid 2WD
34/30/32 mpg
6.Toyota Yaris (manual) 29/36/32 mpg
7.Toyota Corolla 28/37/31 mpg
8.Honda Fit 28/34/31 mpg
9.Nissan Versa (tie)
Scion xD (tie)
27/33/29 mpg
10.Hyundai Accent 27/32/29 mpg

Source: U.S. Environmental Protection Agency

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