All three U.S. auto manufacturers have been praised by the U.S. Department of Energy for their hard work on the new vehicles which have great fuel economy.

Chrysler famous for huge gas guzzling autos has received $14.5 million for the flexible combustion system which will be installed in minivans and vehicles alike. The company has brought several interesting projects to the 2010 Detroit Auto Show which took place a few days ago. One of them was a V6 engine which improves fuel economy of big vehicles by 8 percent. The 2011 Jeep Cherokee will be the fist auto equipped with this motor.

The Department of Energy gave $15 million to Ford for the idea which uses several engine technologies to improve fuel efficiency by 25% in medium and large sedans. The automaker is planning to introduce 9 new and upgraded engines along with 6 new transmissions. Among them there is the V6 motor for the 2011 Ford Mustang which outputs 305 horsepower and gets 30 mpg on the highway.

General Motors also worked on the efficiency of the vehicles. It received $7.7 million for the technology which improved the use of gasoline in Chevrolet Malibu by 25%. In general the company is concerned about fuel use in all of its autos, even full-sized trucks.