Found this on another Diesel Site... ... ... ... ... .....
While out on our trip a few weeks ago, I started runnng into the new ultra-low sulfer fuels and in one case was forced to use it due to the "regular" fuel wasn't available at that particular fuel station. I didn't see any ill effects and was actually quite impressed at the slight improvment in fuel mileage I experienced.
I've heard rumors that running the new fuel in the older engines can cause trouble, so I took the libery of contacting Cummins directly. The following is my question and what they had to say... .
Details:
Comments:
I own a 2003 Dodge Ram with your 305hp HPCR 5. 9L engine. I am starting to see the new ultra-low sulfer (ULS) fuel showing up at the pumps. What do I need to know regarding this fuel and it's use in my engine?
Solution:
Thanks for your Email message.
There are many rumors circulating about the effects of sulfur being in diesel fuel or sulfur being taken out of diesel fuel. Diesel fuel without sulfur is just as good, in all respects except one, when compared with today's fuels with sulfur.
Diesel fuel, in the United States, must meet a lubricity standard. The producers adjust the lubricity before they distribute the fuel. No further additives are needed to ensure proper fuel system lubrication.
The only negative effect of taking sulfur out of fuel is that the fuel becomes more expensive, somewhat negating the inherent cost advantage of running diesel engines when compared to other fuels. As we are certain you know, sulfur doesn't jump out of the fuel on command. It has to be removed using specialized equipment and chemical processes that add to the expense of producing the fuel.
There is an effect on diesel engines from the use of low or no sulfur fuel which we expect to be positive. The blowby gasses that normally pass through the engine crankcase will contain less or none of the chemically reactive sulfur and its compounds. This will tend to keep the engine oil cleaner during operation and allow important engine components like bushings, bearings and piston rings to live longer.
Diesel fuels containing sulfur or no sulfur each have the same specific heat, about 20,000 BTUs per pound. For that reason they give the same amounts of work for the same amount of fuel. That means the fuel economy per gallon will not be affected.
Over the years we have seen fuel economy decrease, somewhat, as diesel engine designs have been modified to meet the lower NOX limits imposed by government. This has been totally unrelated to sulfur in the fuel.
With lower sulfur fuels it is possible that some exhaust after treatment devices (catalytic converters) may be used to better effect, making it possible to further decrease harmful exhaust emissions.
If you use diesel fuel that does not meet the new federal low sulfur requirements that are going into effect for 2007, in a 2007 vehicle that requires the new fuel, it will produce particulate matter that will cause rapid plugging of the exhaust particulate trap. We don't anticipate producing engines for such vehicles until 2007.
We thank you for your interest in Cummins products. Please let us know if you need assistance in locating the nearest Cummins-authorized Dealer or Distributor Service Provider. For assistance in locating a Service Provider, feel free to use Cummins Dealer Locator, which can be found on Cummins website:
http://wsl.cummins.com/ServiceLocator/jsp/controller.jsp?action=showworldmap
Please let us know if you have other questions and if away from your computer or have a time-critical request that needs more urgent attention, feel free to call us toll-free (from North America) at 1-800-DIESELS (343-7357). Customers may also call Cummins switchboard 1-812-377-5000 (worldwide toll call) and ask for the 800-DIESELS Call Center for assistance.
Cummins Email (via webpage):
http://www.cummins.com/cmi/content.jsp?siteId=1&langId=1033&menuId=6&overviewId=33&menuIndex=7
Customer Assistance Center
Cummins, Inc.
Columbus, Indiana, USA
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