Ed White
Kelowna, BC, Canada
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Needed to add one additional piece of information after reading some of the posts about diesel fuel around the world. Use the following link to see sulfur levels in diesel around the world:
http://en.wikipedia.org/wiki/Ultra-low_sulfur_diesel
As can be seen by reading the paragraph about Sweden, the 0% sulfur fuel there is NOT generally available for public use. It is made available for use in special applications where pollution control is important.
Most of the rest of Europe is presently on 10 ppm and North America is on 15 ppm (parts per million). From a "pollution" perspective, the difference between 10 ppm and 15 ppm is insignificant.
It is true that the Smart Car diesel engine, amongst others, did not meet US emissions standards in 2008. It does not automatically follow that just because the fuel being used is only 10 ppm sulfur that the emissions produced by a European engine are acceptable. If the diesel exhaust is not properly treated, pollutants are still high, even though there is not much sulfur present
* This post was
edited 02/04/12 11:00pm by Ed White *
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moisheh
North America
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ED: Very good information. I had heard that the Duramax's were sensitive to the wrong fuel. I was in a 2012 Monaco product this week and it actually had a switch for forcing a regen! I wonder if that Duramax records the fault after using the bad fuel. If so the warranty on any fuel related problems are not covered. Same for driveability issues. GM issued a directive that when a Tech hooks up the shop computer and it shows that fault they have to take a digital photo of the screen and record the VIN # on the GM computer. That truck will then be flagged anytime it needs service. If you are selling that truck and a dealer does a service history report that info will show up.
Moisheh
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Ed White
Kelowna, BC, Canada
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Good question Moisheh whether or not the GM trucks register the fault after using LSD fuel in Mexico. The answer is yes and no.
When the NOX monitor notices excessive levels of NOX in the exhaust, even though DEF is being injected into the exhaust stream, it triggers the driver warnings and "latches" the code in the engine computer. This means that a record of the fault remains, at least initially, even if a code reader is used to erase the readable fault codes.
However, if the NOX monitor successfully goes through more than 3 cycles of normal NOX levels, it is my understanding that the memory is cleared. In any case, even if the memory was NOT cleared, the code does not indicate bad fuel, it indicates a problem with NOX levels and attributes it to bad DEF. There is no code, at least to my knowledge, that registers sulfur levels in the fuel.
So, the bottom line is, once the vehicle returns to using ULSD in the USA, it quickly returns to normal with no ongoing codes present. The NOX monitor runs from time to time during normal driving so 3 cycles can be achieved fairly quickly.
It would be great to have a switch to force a regeneration, but I doubt that it will ever come for pickups.
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moisheh
North America
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Ed: I wasn't thinking of the new vehicles with DEF but rather the ones that just have a DPF.
Moisheh
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Ed White
Kelowna, BC, Canada
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All of the pickups with just a DPF, that is, 2007.5 through 2010 model years, have NO issues with Mexican fuel and do not register any codes which would cause problems later at a dealership.
EPA and manufacturer testing as far back as 1999 showed that DPFs exposed to high sulfur fuels recovered close to 100% of their effectiveness after returning to Ultra Low Sulfur Diesel.
The only exception is DPFs exposed to high sulfur fuels for more than 40,000 miles, after which there is permanent degradation which reduces the effectiveness of the DPF. Even then though, there is no way to identify the reduced efficiency as being a result of using higher sulfur fuels.
Mexican fuel has proven to be a non-issue for 2007.5 through 2010 model years. I have been monitoring the situation on diesel forums since early 2007 and have yet to find a single case of problems proven to have been caused by using Mexican fuel.
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moisheh
North America
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Ed: At the risk of reapeating myself Your info is always relevant to pickup trucks. Motorhomes with large diesel engines are quite different( ISL,ISM and ISX) Our ISL is very sensitive to the Mexican fuel. We do add a slight amount of this fuel as a safety factor( never know when you will be stuck somewhere and have to run the gennie. Maybe 75 litres to 65 gallons. This does not affect anything. But twice I tried 150 litres to about 50 gallons ( call it 50/50) and within 150 miles it went into a full active regen. In 35,000 mils those 2 regens were the only full ones we have ever had. A few times we had the quicky version. The full regen is scary. There is so much heat you can smell it from the front of the MH. The rear "hatch" is extremely hot and when I opened it anything metal is too hot too touch! The good thing about Mexican diesel is that it has a higher cetane rating. Our Bluebird runs like a charm on this fuel. Others with older MH's have also reported better performance. If I had a PU or MH that required DEF I would make sure I had lots before crossing the border. You might wait forever for a delivery from the USA! You mentioned NAPA but I have yet to see a NAPA store in Sonora. Lots of Autozones.
Moisheh
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Ed White
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1.
Yes, the best way to avoid emergencies over DEF supplies is to take with you into Mexico much more than you are likely to need.
2.
I've seen the evidence that NAPA on the Baja is excellent for delivery of special orders. They have a shipment from the USA once a week and seem to be able to order most things that appear on the napaonline website. Delivery time is typically 7 to 10 days depending on when the order is placed relative to a shipment date.
I am not aware of anyone trying to order DEF or other items from the USA through AutoZone, but they should be able to do it, if they want to. USA products should be able to come in without problems under NAFTA.
3.
I'm not an expert on the large diesel engines in motorhomes, but I have significant knowledge about the emissions systems used on all diesels post 2007. Based on this knowledge, there is no reason to believe that higher sulfur fuel will itself trigger a regeneration, because regenerations are triggered by soot load in the DPF measured as pressure drop across the DPF.
Sulfur in the fuel forms compounds which can temporarily reduce the capacity of the DPF, but are in extremely tiny amounts compared to the overall soot mass, and are not enough to be noticed by a driver.
Much, or even most, of the sulfur actually flows straight through the DPF and exits the tailpipe as sulfur compounds like sulfuric acid (H2SO4) and oxides of sulfur. Keep in mind, the maximum sulfur content of Mexican fuel is 300 parts per MILLION, which is very tiny compared to the carbon content of the balance of the fuel.
I can't explain why you experienced unusually hot regenerations Moisheh, but I suspect it was unrelated to sulfur in the fuel.
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moisheh
North America
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Thanks Ed: I think your figure for the Mexican fuel may be incorrect. It is more like 500 PPM. Same as 5 years ago.
Moisheh
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Ed White
Kelowna, BC, Canada
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Yes, 500ppm is correct. Thanks for catching that. Somehow hit the wrong key while typing. Doesn't alter the discussion as far as the DPF is concerned.
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RobertRyan
Australia
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Ed White wrote:t is true that the Smart Car diesel engine, amongst others, did not meet US emissions standards in 2008. It does not automatically follow that just because the fuel being used is only 10 ppm sulfur that the emissions produced by a European engine are acceptable. If the diesel exhaust is not properly treated, pollutants are still high, even though there is not much sulfur present
Correct the diference is minimal but try and run these engines on 500ppm, then if it is Euro V, electronic controls will shut the engine down.
A Tier compliant US diesel on the other hand as I have posted a few times on these forums cannot be used under Euro V regs, as the C0 2 levels breach the regulations.
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