Validity
This Executive Order approved the specified parts on on September 9, 2005.
As of Monday, January 20th, 2025 this Executive Order has not been overturned or superceeded.
This Executive Order approved the specified parts on on September 9, 2005.
As of Monday, January 20th, 2025 this Executive Order has not been overturned or superceeded.
Models | Modification |
---|---|
1987 through 2004 model-year 4-stroke diesel engines used in heavy-duty on-road vehicles. This exemption excludes all engines equipped with an exhaust gas recirculation system and/or an aftertreatment emission control system such as a catalytic converter or a diesel particulate filter. | This exemption is only valid provided the engines meet the following operating conditions: (1) the engine exhaust temperature is greater than or equal to 240 degrees Celsius for 40 percent of the typical duty cycle, (2) the NOx to PM ratio is at least 8, and (3) the engine is operated using diesel fuel with a maximum sulfur content of 500 ppmw. |