A handful of Arco's throughout CA sell ULSD which is 15ppm or less and we have been using it for the most part the past year...a lot less soot under full throttle!
Juicy tidbit for you VW diesel engine owners
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Off road diesel as is used in construction equipment has a sulphur limit of 0.5%. While the Cummins, CAT and other industrial engines are heavy duty, I doubt that sulphur at that level deteriorates an engine unless it is neglected.
I have an old Mercedes 5 cylinder turbodiesel, and a more modern GMC Duramax diesel pick-up, both of which have no catalyst. From the other discussion groups I get on, the general advice is that higher sulphur such as up to 0.5% can be preferable as it provides more lubricity to the fuel injection system components. Also, I note that using off-road diesel is highly illegal as it is untaxed, and also causes more emissions than the more modern engines are certified for, as they are certified on lower sulphur fuel. Nevertheless, using off-road diesel does not void the GM warranty on the Duramax diesel.
Also, after Katrina, there were fuel shortages and distribution problems. For a couple of months, the EPA suspended the sulphur limits so as to allow the higher sulphur off-road diesel to be burned as on road fuel.
I have an old Mercedes 5 cylinder turbodiesel, and a more modern GMC Duramax diesel pick-up, both of which have no catalyst. From the other discussion groups I get on, the general advice is that higher sulphur such as up to 0.5% can be preferable as it provides more lubricity to the fuel injection system components. Also, I note that using off-road diesel is highly illegal as it is untaxed, and also causes more emissions than the more modern engines are certified for, as they are certified on lower sulphur fuel. Nevertheless, using off-road diesel does not void the GM warranty on the Duramax diesel.
Also, after Katrina, there were fuel shortages and distribution problems. For a couple of months, the EPA suspended the sulphur limits so as to allow the higher sulphur off-road diesel to be burned as on road fuel.
well the wear also increases with the percentage of sulphur...very low sulphur fuel is actuelly better for your engine.
for a while there all of the local diesel pumps were selling red dye offroad as a taxed fuel because of the shortages. the feds also suspended dipping for a while.
Not all off-road diesel in the USA is higher-sulfur than the on-road. In many areas of the non-CA West at least, off-road diesel as used in agriculture is identical in all respects to on-road, excepting for the addition of red dye to distinguish it for ease of fining by the DOT.
The higher, 0.5% sulfur fuel is 'better' for the engines because at that sulfur level it does NOT shorten engine life in the ring area, but it does EXTEND fuel pump life. So in actual fact, higher-sulfur (up to 0.5% at least) fuel is 'better' for your engine. I use quotes around the term 'better' because, like in most things, there are alternative methods of achieving the same objective so long as financial considerations are ignored.
The higher, 0.5% sulfur fuel is 'better' for the engines because at that sulfur level it does NOT shorten engine life in the ring area, but it does EXTEND fuel pump life. So in actual fact, higher-sulfur (up to 0.5% at least) fuel is 'better' for your engine. I use quotes around the term 'better' because, like in most things, there are alternative methods of achieving the same objective so long as financial considerations are ignored.
actually since the sulfer levels have dropped in the fuel, fuel milege in the big OTR trucks has dropped. All the long haul drives that come to my shop swear by fuel additives for milege gains, namely lucas. a gallon of lucas is expensive, but they say itll get them 1 to 2 mpg on the long haul, so its well worth it.
I remember reading a research paper about sulphur having nothing to do with lubrication. It was actually the amount of oil in the fuel(I can't really remember it at all)the sulphur was just a mask for it. It involved ULSD and regular diesel and bunch of test and comparisons either way. H E L L I think Biodiesel might have been thrown in there too.
It was signed off by a couple of chemist and professors for what it's worth.
Bottom line they said was sulphur has nothing to do with lubricity.
It was signed off by a couple of chemist and professors for what it's worth.
Bottom line they said was sulphur has nothing to do with lubricity.
Sulfur does not provide lubricity. The process that removes sulfur removes the components that do provide hte lubricity, and the refinery adds back lubricity additives.
The engine can work with whatever sulfur level it was built for. I've run diesels on heavy fuel with 3.5% sulfur (yes, 3-1/2%!), with TBN 70 cylinder lube oil, and running 24 hours daily about 20 days a month showed liner wear good for about 20 year liner life.
Ken
The engine can work with whatever sulfur level it was built for. I've run diesels on heavy fuel with 3.5% sulfur (yes, 3-1/2%!), with TBN 70 cylinder lube oil, and running 24 hours daily about 20 days a month showed liner wear good for about 20 year liner life.
Ken
With all of the "hit or miss" information about VW/Audi oil change intervals, anyone with one of these vehicles, whether it be gas or diesel, should just change the oil and filter every 5,000 miles and be done with it.
Why? Most PD TDI's (millions of them!) in Europe are run for at least 10,000 miles, and there are no horror stories except when the wrong oil is used. In NA, with ULSD, you're on the same level. None of the UOA show a problem with 10,000 OCIs do they?
It is not "hit or miss", they are clearly defined and followed by most. The OP just went by on what he saw for a different brand, in a different country, on another continent.
It in no way relates to the US.
It has always been 5k first change 10k thereafter for TDI's. The only change has been oil requirements so lets stop perpetuating this lie.
While we're talking about diesel fuel differences, another manner in which US fuel is inferior to Western European fuel is cetane rating. Over there ~ 50 cetane is common, while here 40 is the norm almost everywhere diesel is sold, and only a few stations sell "premium" diesel with 47 or higher. In Europe I doubt that our 40 cetane stuff could even be legally sold as diesel fuel. So I wonder how our lower cetane ratings affect the VW TDI long-term?
JHZR2
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It does and it doesnt. The thing is this - many large polyaromatics have a sulfur bound to them, compounds like dibenzothiophene. Those large double rings with pi-bonds and substituted methyl groups, etc. provide lubricity by virtue of (essentially) their aromatic ring makeup.
In doing conventional refinery processes, hydrodesulfurization was performed. It was done at mild conditions, because Henry's law, coupled with low selectivity catalysts caused a need for high pressure hydrogen ($$$) that had to be balanced with not putting too much in.
HDS produces H2S and some hydrocarbon fragments from a big molecule and H2. The problem is that especially with aromatic mlecules, hydrogen will go in and remove double bonds in the ring structure, effectively destroying the while thing. The refineries dont like that because they want the hydrocarbons to stay what they are - they dont want to waste hydrogen 'hydrogenating' the regular HCs.
Fast forward to ULSD... Same problems exist, same inefficiencies of HDS processes, only now we need to get more or less every sulfur compound out. That includes the 2,3,7 trimethylbenzothiophene and 4,6 dimethyldibenzothiophene, highly refractory, sterically hindered compounds that would remain as-is in finished product of old, but now need to be processed.
So, what do we do to obtain this? Higher hydrogen pressure (remember Henry's law and forcing a gas into a liquid), which then hydrogenates more polyaromatics, even the non sulfur-bound ones, in the name of getting the organically bound sulfur. THese severe processing conditons cost more hydrogen due to its cleaving of double bonds (every mole of double bonds cleaved, you use a mole of H2), removal of many large polyaromatics, and thus overall higher cost due to the extra used hydrogen (not cheap), and less lubricity due to the byproduct of severe HDS, which is very few aromatics.
The good news is that cetane is essentially th einverse of octane, so a higher volatility fuel yields a higher cetane... well, get rid of those pi bonded heavies for the most extent, and youve got more smaller, more volatle rings and chains in there, and thus you get a cetane boost.
I wouldnt doubt that our ULSD is 45-47...
JMH
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