Truckload carrier Western Express of Nashville has ordered 900 Freightliner Cascadia tractors powered by Detroit Diesel Corp. DD15 engines meeting the 2010 federal emissions standards. The order is the first installment of a three-year agreement to purchase 2,800 trucks from Freightliner, according to Wayne Wise, the fleet’s president and CEO.

The EPA 2010 DD15 diesel engines use selective catalytic reduction (SCR) to meet the stricter emissions rules while improving fuel economy by up to 5%, according to Daimler Trucks North America, the parent of both Freightliner and DDC.

“This continues our commitment to going green, reducing our carbon footprint, and the EPA SmartWay program.,” said Wise. “We delayed our purchase of new tractors in anticipation of this new technology.”