http://www.dieselplace.com/forum/smileys/Confused.gifAt times the amount of information on a particular topic can be overwhelming. There has been much discussion about the pros and cons on using fuel additives, but how does the fact that the fuel might be "low sulphur" or not, come into play? What exactly does the sulphur do, or doesn't do? I've been hearing that eventually the government will mandate that all fuel will be "low sulphur", and that the refineries already have the capacity to manufacture it, but due to the expense, are waiting to be forced to. How will it's use affect maintenance and the life of the motors? Just curious.

We currently have "low sulphur" diesel fuel in California. Around the corner in 2006 is "ultra low sulphur" diesel for everyone (all 50 states). The government is mandating the sulphur be removed due to tightning emissions standards on diesel engines around the corner in 2007. It is envisioned that some sort of exhaust after-treatment will be required to meet these standards (similar to todays catalytic converter on gasoline engine cars).


In the "process" of refining ultra low sulphur diesel, the lubricity of the diesel fuel is lowered (by lowering the aromatics in the fuel). Refineries will have to raise the lubricity of the fuel by including addititives. My personal opinion based upon researching this topic (and I am not a petro chemical engineer) is that as long as the lubricity is kept to acceptable levels the average diesel engine will be better off with this cleaner burning new fuel. Our California Air Resources Board (CARB) has had several industry meetings to debate the new diesel fuel - the two sides debating the issues were engine/component manufactures (wanting more lubricity) and the refiners (of course wanting to do less). By the way, our California "low sulphur" diesel fuel sold today typically has a cetane number in excess of 50. My measured results were 52. The nation average is probably around 45.

Beat me to it...oh well....


Low-sulfur diesel is already here.


Ultra low-sulfur diesel is just around the corner for most of us and is already at the pumps in parts of <st1:State><st1:place><st1:State><st1:place>California</st1:place></st1:State></st1:place></st1:State>.


North American low-sulfur fuel on average has less than desirable lubricity.


Of the characteristics that make "premium diesel" premium, increased lubricity is officially not one of them.


The primary point of contention regarding additives is emulsifying versus demulsifying, while GM has been unambiguous as to what is "permissible," read acceptable when it comes warranty time. Generally both demulsifying and emulsifying additives claim to increase lubrication.


Perhaps the today's "lower quality" North American fuel coupled with the higher operating pressures of common rail injection will lead to disappointing fuel system component failures. This is why some folks run secondary fuel filtration and/or additives.


An interesting thing is that all diesel vehicles may not necessarily be "grandfathered" for 2007. Yes, it looks like retrofitting might be around the corner for at least some. I expect the hot-rodders amongst us--those who pour out all of that black smoke--will start to face more penalties, as one of the larger arguments against diesel motoring is the soot or particulate pollution, as the body of evidence indicating that it is a serious health hazard continues to mount. As an aside, I know many diesel owners who are also outdoorsmen and yet they will not hesitate to modify their vehicles in ways that lead to more toxic emissions and thus further pollute the environment...hypocrites or merely shortsighted...dumb, IMO.


Lots of info out there.... Take a look at this:http://www.arb.ca.gov/fuels/gasoline/meeting/2003/022003bosch.pdf

Ultra low sulfur fuel is suppose to have additives to make up for the lost lubricity. My biodiesel supplier claims the new Ultra low sulfur lacks the needed lubricity. No specifics given.


Does the state of California test the fuel on a regular basis to ensure the specifications for the fuel are being met?


Probably not.


I do not trust this fuel as it applies to our trucks because there is IMHO a lack of data showing it will have at least the lubricity of the past. And that is an issue also--California fuel had lower sulfur than the rest of the country.


I believe Bosch had reliability versus lubricity of the fuel for the injectors and pump.


What is really needed is some testing showing how the new Ultra low sulfur fuel measures up--that way we can see whether or not we should use additives.


Two local refineries in Southern California have been producing the ULSD for some time.

EMA 1999


" All diesel fuels which do not contain detergents have a tendency to form carbon deposits on fuel injectors. It has generally been found that low sulfur fuels and thermally unstable fuels have a greater tendency to form theses deposits. Detergent additves will prevent carbon deposits, which interfere with fueling and fuel spray patterns, from forming.


Dirty injectors will invariably give rise to higher smoke levels in all equipment and, in some equipment, can limit power by restricing flow."


Engine Manufacturer's Assc. and the National Conference on Weights and Measures are our watch dogs for fuel quality or lack there of.