Feb 1, 2009 12:00 PM

Navistar plans to use an in-cylinder exhaust gas recirculation (EGR) system to meet the U.S. EPA 2010 diesel emissions regulations rather than employing selective catalytic reduction (SCR) because it is a simpler solution, officials said during an exclusive briefing for Penton Transportation Group editors.

The in-cylinder EGR system “is transparent to the customer and essentially continues on the same path we've been on,” said Tim Shick, Navistar director of business and product strategy.

Navistar is the only U.S. engine manufacturer to use EGR.

SCR systems currently under development require a diesel exhaust fluid, a liquid chemical also known as urea.

Shick said the SCR approach does improve fuel economy, but Navistar's research showed that by volume the amount of urea added equals the amount of diesel fuel saved. Furthermore, SCR requires more sensors and diagnostics, additional hardware, “and a complex control strategy.”

Navistar's EGR solution is “a mature technology with a proven track record,” he said, and noted that EGR has no adverse economic impact over the product lifecycle.

In addition, with EGR systems, there is no additional components or weight and no concerns with urea distribution. All chassis configurations are maintained, and operational maintenance and serviceability issues are reduced.