In 1976 it was the Dodge Aspen.

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Of American automakers, though, Chrysler is the worst offender, with six vehicles on last year's "dirtiest" list (the Jeep Commander, Jeep Grand Cherokee, Dodge Durango, Chrysler Aspen, Dodge Ram 1500 and Dodge Dakota), and five this year.

FORBES: Vehicles

Some examples: the Jeep Patriot and Jeep Compass compact SUVs, or the Dodge Durango and Chrysler Aspen SUVs.

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With a workforce of 2, 100, this makes the firm's slow-selling Dodge Durango and Chrysler Aspen sports utility vehicle (SUV) models.

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Chrysler has plenty of gas-guzzling SUVs on the way, too, including two- and four-door versions of the iconic Jeep Wrangler, an all-new Dodge Nitro sport utility and the even larger Chrysler Aspen.

FORBES: Magazine Article

Chrysler has a handful of smaller-volume hopefuls, like a redesigned Chrysler Sebring sedan, a new Chrysler Aspen SUV, a small SUV for Dodge called the Nitro and a Jeep crossover called the Patriot.

FORBES: Detroit, Downsizing