DETROIT - As more public and commercial fleet managers take steps to green their operations, Ford Motor Co. has responded by making its 2011 line of F-Series Super Duty diesel pickup trucks compatible with biodiesel blends up to B-20, according to Biodiesel magazine.

"We have a fleet advisory board and we go through a very specific process of communication with our customers, and we are always asking them what they are looking for," said Ford spokesperson Anne Marie Gattari. "Biodiesel compatibility kept coming up over and over again and it speaks to fuel economy, it speaks to an environmental solution, and it allows an opportunity for us to advance our technology."

For vehicles currently on the road, Ford, like most all OEMs, has approved biodiesel blends up to B-5 so increasing the methyl ester compatibility of its models, regarding emissions compliance, engine components and other specs, required some considerable modifications. "The new 6.7L Power Stroke V-8 turbocharged diesel will employ an after treatment system to help comply with 2010 federal regulations to reduce nitrogen-oxide levels in diesel emissions by more than 80 percent compared with the previous standard," the company stated.

The Ford aftertreatment system for its new clean diesel technology involves a three-stage process. First the exhaust stream enters a diesel oxidation catalyst, which converts hydrocarbons into water and carbon dioxide. NOx is then scrubbed from the emissions after receiving an injection of diesel exhaust fluid and then passing through a selective catalytic reduction chamber, turning the gas into water and inert nitrogen. Lastly, a diesel particulate filter traps any remaining soot, periodically burned off in a process known as regeneration. "The regeneration process sees temperatures in excess of 600 degrees Celsius to burn away soot," Ford stated.