Update Regarding Diesel Fuel in Mexico - September 27, 2017
The Mexico Snowbird Season for 2017/18 is fast approaching, so here is an update regarding sulfur levels in Mexican diesel fuel and the potential for negative impacts on late model diesels. Please note that I am not a Pemex employee, so I can not guarantee that information provided by Pemex about the availability of ULSD is completely reliable, but lab testing of some random fuel samples, and data from diesel owners driving in Mexico, does appear to confirm the latest Pemex information.
Several things have become abundantly clear over the 10+ years since I first began researching this topic and started collecting data from owners of a wide range of diesel powered vehicles:
1.
All diesels up to and including the 2010 model year, irrespective of manufacturer or vehicle type, have no significant problems from the use of higher sulfur Mexican diesel fuel (LSD). The most noticeable โsymptomโ, only apparent on 2007.5 through 2010 model years, MIGHT be occasional blue smokey exhaust during regeneration cycles. (Regeneration cycles burn soot out of the Diesel Particulate Filter (DPF) from time to time, and blue smoke can occur when sulfur deposits are mixed with the soot). The majority of owners though will not even see blue smokey regenerations, so will be unaware whether or not their vehicles are burning Mexican diesel.
IN SUMMARY: If you own a diesel vehicle of any model year prior to 2011 you can use Mexican diesel fuel without taking any special precautions.
2.
There is a POTENTIAL for 2011 and later diesel vehicles, the ones that use Diesel Exhaust Fluid (DEF), to experience problems while using Mexican LSD. (Dodge RAMs of 2013 and later model years fall into this category.
Within this group:
(a)
CLASS A MOTORHOMES:
I have never received a report of any Class A diesel pusher motorhome having any type of sulfur-in-fuel related problem. This is probably because these vehicles are very heavy, which keeps exhaust gas temperatures elevated, discouraging sulfur compounds from settling out in the exhaust/emissions system. In addition, their exhaust systems are relatively short, so they heat up quickly and stay hot, again discouraging the deposit of sulfur compounds that could interfere with the functioning of the emissions system.
IN SUMMARY: Based on all of the data available at this time, Class A diesel pushers have no negative reactions to the use of Mexican LSD
(b)
SPRINTERS:
Sprinters are a very large sub-group of motorhomes that are commonly seen in Mexico. They are relatively heavy for their size, so their exhaust/emissions systems stay hot, which discourages sulfur deposits. However, I have two verified reports of post-2010 Sprinters going in to modes where the number of starts is being restricted, with warnings of a shutdown after those starts have been used. In both cases though the vehicles โhealedโ themselves, presumably after a regeneration cycle burned soot and sulfur out of the exhaust/emissions system.
Based on discussions with the owners of those Sprinters, the evidence suggests that Sprinters will not typically have any issues using Mexican LSD unless the vehicle is used for numerous short trips for shopping, restaurant visits, etc after reaching a winter destination. These short trips do not fully heat the exhaust system, which allows sulfur compounds to collect in the Selective Catalytic Reducer (SCR).
IN SUMMARY: Sprinters very rarely experience serious issues with Mexican LSD, and probably only when the vehicle is used for frequent short trips that do not fully heat the exhaust system. Owners planning to use their Sprinters for local transport once they reach their final destination should try to carry extra ULSD and use a 50/50 mixture with Mexican LSD after reaching the final destination. A 50/50 mixture of ULSD with Mexican LSD has been shown to cause no sulfur related issues across a wide range of vehicle types.
(c)
DODGE RAM PICKUPS:
Dodge RAM pickups have been the least likely diesel pickups to experience any issues with Mexican diesel fuel (LSD). The most frequently reported issue has been excessive consumption of DEF in 2013 and later models as the emissions system injects more and more DEF to compensate for the sulfur contamination of the Selective Catalytic Reducer (SCR) between regenerations.
There is, however, some uncertainty going forward because Dodge has apparently recently negotiated a settlement with the EPA over allegations of improper reporting/monitoring of emissions. It is my understanding that Dodge has agreed to correct the โproblemโ by reprogramming trucks during normal service visits to dealerships. What is not yet known is how the reprogrammed trucks will react to the presence of sulfur in the fuel, so Dodge owners need to be aware that there is a potential for new fuel-related problems.
IN SUMMARY: Dodge RAMS have generally been symptom free while using Mexican LSD but there is a new potential for issues because of emissions programming updates by Dodge. It may be wise for 2013 and later Dodge owners to obtain a tuner, such as the one made by Edge Products, that can force a regeneration cycle to burn sulfur out of the system. A regeneration should then be triggered if any emissions related warnings are displayed.
(d)
FORD PICKUPS:
Ford diesels generally have not exhibited any issues while using Mexican LSD, but I have three verified cases of emissions related COMPLETE SHUT DOWNS after the vehicles were used locally in Mexico for extended periods on Mexican LSD after arriving at a winter destination.
IN SUMMARY: Ford diesels are usually symptom free while using Mexican LSD but there is a potential for issues if the vehicle is driven on short trips on Mexican LSD once the winter destination has been reached. It would be wise for 2011 and later Ford owners to obtain a tuner, such as the one made by Edge Products, that can force a regeneration cycle to burn sulfur out of the system. A regeneration should then be triggered if any emissions related warnings are displayed.
(e)
DURAMAX POWERED PICKUPS (GMC and CHEVROLET):
Duramax powered diesels are the most sensitive vehicles to sulfur in Mexican fuel. They often enter speed limitation modes, and can end up in limp mode (5mph) if special precautions are not taken. (Almost as if Duramax is OVER-reporting emissions compared to other diesels). Owners of 2011 and later Duramax diesels should contact me at whitetmp@aol.com if they are planning to travel in to Mexico so that I can make them aware of special precautions that need to be taken. Unfortunately, as of the time of writing, I have not become aware of any tuners available at the retail level that can trigger regenerations on Duramax diesels.
3.
HERE IS THE LATEST INFORMATION REGARDING THE AVAILABILITY OF ULSD IN MEXICO:
(a)
It is NOT POSSIBLE to determine whether fuel is ULSD or LSD by looking at it or sniffing it. The ONLY way to make a reliable determination is with a laboratory test. I have personally collected and run lab tests on samples of fuel from Mexico so I know this is true. If someone says he or she can identify the fuel type without a lab test you need to be skeptical.
(b)
The Mexican Government has set the end of 2018 as the cutoff date for Pemex to supply ULSD at every station in Mexico. If Pemex can not upgrade it's own refineries by then, it has to export the fuel produced by those refineries and import ULSD for domestic use. At this stage it appears that 3 of Pemex's refineries have already been upgraded or the upgrades are close to completion, and more are currently being worked on. As a result of the already completed upgrades, ULSD is becoming more readily available and there are now large areas and corridors where ULSD is standard.
NOTE: It is commonly the case that a station will be pumping ULSD without the knowledge of the attendants, and there will not be any label to indicate that the fuel is ULSD (UBA). Do NOT trust any claims by station attendants that they have, or have not, got ULSD (UBA) at the pumps unless they can show you the fuel manifestโ they typically have NO IDEA where their fuel originates.
(c)
A contact at Pemex recently sent me a copy of the official Pemex list of stations already carrying ULSD. The list is arranged by state and then city or town within the state. I can provide that list to owners of vehicles which may be sensitive to sulfur in the fuel, specifically Duramax owners.
(d)
There is reliable evidence that there is presently ULSD at every Pemex in the Northern Baja, down to and including Jesus Maria, about 38 kms north of the border with the Southern Baja. In additon, all stations in the Yucatan are listed as having ULSD, and the main corridors running from the US Border to Mexico City are mostly stocked with ULSD.
(e)
I have received recent reports from travellers who say they have seen Gulf and Esso stations now open in Mexico, so the marketplace is presently undergoing a major transformation. As a result of these changes, I am convinced that Mexico will indeed fully convert to ULSD by the end of 2018.
Ted (Ed) White
whitetmp@aol.com
September 2017
