Mercedes plans to give the C-Class and GLK SUV a new 2.2-liter diesel engine in North America by 2010. Because of emissions regulations, Mercedes needs to re-engineer the engine to accept BlueTEC technology. A company spokesman said, "The 2.2-liter in the GLK already averages 34 miles per gallon U.S. With BlueTec that will improve to just under 40."

The decision has been made first because of the rising fuel prices and also because of the weak dollar.

You can read all about BlueTEC technology from when Mercedes gave TopSpeed an exclusive look.

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