Like a comfortable pair of shoes, sedans are a good fit

2009 BMW 335d

BMW, not content to let rival Mercedes-Benz bask in the diesel spotlight, is bringing a twin-turbo, diesel-powered 3 Series sedan to all 50 of these United States late in 2008. Like its Teutonic rival, BMW uses urea injection to turn nitric oxides into nitrogen and water vapor, and thereby meeting emissions regulations. The system also doesn't need to be refilled any more often than when owners have the engine oil changed, a move by both automakers to lessen any inconvenience. BMW's diesel is a 3.0-liter, inline-six cylinder, twin-turbo engine that is already sold in other parts of the world. The 335d goes on sale in the fall.

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