Cummins aims to boost heavy-duty diesel efficiency to 55%

The big-rig tractor-trailer trucks that we see on the highway get only about 5.8 mpg of diesel fuel. In tests, the Cummins-Peterbilt SuperTruck-a U.S. Department of Energy-supported advanced technology demonstrator unveiled last year-achieved nearly double that number: 10.7 mpg. If all the heavy-duty trucks in the U.S. were as efficient as the SuperTruck, domestic consumption of oil would fall almost 300 million barrels, a potential $15-billion savings that would reduce the annual fuel outlay of the average Class 8 operator by perhaps $10,000.

And although semitrailer trucks comprise only 4% of the vehicles on America roads, they consume about 20% of the fuel, so improved fuel economy would also cut emissions of CO₂ significantly.