For the fifth time in a row, the Ford F-150 has ranked as the most-American vehicle on the Cars.com American-Made Index.

The index, which the auto Web site releases on a semi-annual basis, ranks the vehicles based on a percentage by cost of parts made domestically, location of vehicle assembly and how popular each car is with U.S. buyers.

"In today's global economy, decisions about buying 'American-made' products can be easily clouded," said Patrick Olsen, editor-in-chief of Cars.com. "Most cars built in the U.S., for example, are assembled using at least some parts that come from somewhere else. Cars.com's American-Made Index helps consumers identify the most-American vehicles based on production location, percentage of domestic parts content, and American sales volume for each vehicle."

Ford was also chosen by consumers as the most-American automaker, according to a recent survey conducted by Cars.com. In the survey, 49 percent of respondents perceived Ford to be the most-American manufacturer. Chevrolet ranked a distant second, with 29 percent of participants calling it the most-American automaker.

Consumer attitudes about domestic versus foreign cars made their choices vary greatly, according to the survey. While most say their buying habits aren't influenced by where a car is made, 27 percent of consumers said they would only consider buying American-made vehicles, and 9 percent would only consider foreign-made cars.

Of those who only consider American-made cars, most are motivated by a desire to support the economy or loyalty to an American-made brand. Those who only buy foreign makes do so primarily because they perceive them to be of higher quality. These buyers said higher-quality cars and better fuel economy from American automakers would make these brands more appealing.

Newcomers to the July 2008 American-Made Index are the Honda Odyssey and Chrysler Sebring. According to Cars.com, the 2008 Odyssey's domestic-parts content rating went up to 75 percent from 70 percent in 2007, which combined with strong sales figures to raise the vehicle to No. 7 on the list.

Chrysler's strongest sellers, the Dodge Ram and Grand Caravan, have never appeared on the index due to low domestic content or assembly in Canada, but its Michigan-built Sebring sedan and convertible made it to ninth place.

Only those vehicles with a domestic-parts content rating of 75 percent or higher are eligible for the American-Made Index.

In keeping with consumer perception, vehicles from Ford and Chevrolet's parent, General Motors, comprised more than half of this year's American-Made Index.

Cars.com American-Made Index
RANK	MAKE/MODEL	ASSEMBLY LOCATION	DEC. 2007 RANK
1	Ford F-150	Claycomo, Mo.; Dearborn, Mich.	1
2	Chevrolet Cobalt	Lordstown, Ohio	2
3	Chevrolet Malibu	Kansas City, Kan.	9
4	Pontiac G6	Orion, Mich.	5
5	Toyota Tundra	Princeton, Ind.; San Antonio	4
6	Toyota Sienna	Princeton, Ind.	6
7	Honda Odyssey	Lincoln, Ala.	N/A
8	Chevrolet Silverado 1500	Ft. Wayne, Ind.; Pontiac, Mich.	3
9	Chrysler Sebring	Sterling Heights, Mich.	N/A
10	Ford Explorer/Sport Trac	Louisville, Ky.	10
Source: Cars.com, Automaker data, Automotive News