Fabio, this was the latest contact with Dave, I am still researching on this one to see what more I can find out.
I have a friend that works for cummins in the R and D dept. That may shed more light on this.
I have done a little more research on the issue of running a vehicle built for ULSD on low sulfur diesel fuel. Probably the best answer I could find is in EPA's regulatory impact analysis for the 2007 and later model year vehicles. In the regulation documents implementing both the emission standards and the ULSD fuel requirements, the EPA responded to the State of Alaska's request for a temporary exemption in rural areas from the ULSD requirement:
The use of high-sulfur (>500 ppm) diesel fuel may cause plugging or increased particulate
sulfate emissions in diesel vehicles equipped with trap systems or oxidation catalysts, and could
impair the ability of oxidation catalysts to reduce hydrocarbons (HC) and CO exhaust emissions.
However, any increase in sulfate particulate emissions would likely have only a minor effect on
ambient PM10 levels in Alaska since current diesel motor vehicle contributions to PM10 emissions
The bottom line is that high sulfur fuel would cause higher emissions and might clog the emission control system. That's all I can find. The contact at EPA for more detailed information is:
Charles Schenk 734-214-4700, schenk. Charles@epa. Gov
I hope this helps.
Puget Sound Clean Air Agency
Wednesday, October 21st, 2009 AT 5:11 AM