Manufacturers now certified by the EPA to meet the most stringent diesel emissions standards in the world include Caterpillar, Cummins, Detroit Diesel Corp., International, Mack and Volvo. With 94 percent of goods shipped via diesel trucks, the life-cycle emissions of any products will fall as new trucks replace aging rigs on the road. Once new trucks fully replace the existing fleet, EPA predictions put the reduction in emissions of smog-forming gases at 2.6 million tons each year, and soot emissions at 110,000 tons annually.
Analysis: With clean(er) diesel technology now on the market via new 2007 truck models, governments need to look at incentives to get old trucks off the road. All the hard work by the truck and engine manufacturers to meet the EPA rules won't amount to much if it takes thirty years to turn over the fleet.