Meeting the challenge

| January 23, 2007

If you have a 2007 engine, you are required by law to fuel with ULSD. Even if you have an older engine, it could be a good idea.

By now, you’ve seen plenty of the new ultra-low-sulfur diesel out there, and you’ve probably heard rumors about its potential effects on your truck – both good and bad.

If you’re driving a truck with a 2007 engine, you are required by law to fuel with ULSD, but even trucks with older engines could benefit from using the new stuff exclusively (see “Advantages of ULSD” on p. 88).

ULSD is tailor-made for trucks with 2007 engines and is only required in those trucks. The reason for requiring the new fuel is that sulfur goes right through the engine and into the exhaust, where it will deposit in the Diesel Particulate Filter used on trucks with 2007 engines and interfere with the burning off of soot.

ULSD is being so widely distributed in part to minimize the chance that the driver of a 2007 vehicle would use the wrong fuel. Also, the sulfur in fuel combines with carbon and tiny amounts of unburned fuel to help create soot particles, so dropping the fuel sulfur will help reduce the total amount of particulate a truck puts into the air. Even older trucks without a DPF will be spewing out less particulate when running on the new fuel.

Still, the new fuel isn’t perfect. It comes with its own share of challenges, but they’re nothing you can’t handle if you know what to watch for.

Higher price, less energy
The new fuel will cost a few cents more per gallon, and it may have a slightly reduced energy content, meaning a very slight increase in fuel costs.

So far the volatile diesel market has hidden the effect of increased cost related to removing sulfur. Because all the oil companies need to employ the process to make most of their fuel, competition in the market should minimize the effect.

If you are concerned about fuel costs, there are plenty of ways to save 1 percent or more of the fuel you burn and keep from experiencing a drop in miles per gallon or even fuel cost. Being more careful about idling unnecessarily or fitting your vehicle with any kind of device that reduces the need to idle will help. So will being careful about shifting progressively, upshifting early and downshifting late while in the higher gears, and leaving early so you’re not so tempted to drive any faster than necessary. Just cruising with traffic in order to avoid frequently needing to stab the brakes can help a lot.

Although refiners were estimating energy content of ULSD might be as much as 2 percent less than the power in LSD, Al Mannato, the American Petroleum Institute’s fuels issues manager, says there are indications the refineries are improving their performance as they gain experience and making ULSD that is closer to the energy content of LSD than originally anticipated.

Fuel filter plugging
The petroleum industry, including the Clean Diesel Fuel Alliance, recommends that truckers watch for fuel filter plugging or fuel system leaks as ULSD works its way through the system.

Karyn Leonardi-Cattolica of Shell’s U.S. media center says the problem with filter clogging is a result of the new fuel’s slightly different composition. Such changes sometimes loosen deposits that are normally stuck in your tank or tanks, and this allows them to be pulled out with the fuel. You should just carry an extra set of filters till you’ve run a number of tanks of ULSD, in case you get enough junk in your fuel to fill up the ones that are on there.

As for leaks, they are only likely to occur with older vehicles – especially older, high-mileage engines that were built before the last reduction in fuel sulfur in 1993. It’s the same kind of situation here as inside the tanks – since the fuel’s different, it affects the seals differently and may cause them to shrink a tiny bit.

“A small number of vehicles may require preventive maintenance in the form of upgrading certain engine and fuel system seals that may not perform well in the transition to the new fuel and could leak,” says Leonardi-Cattolica. Fortunately, she reports, the last change in fuel sulfur content changed the fuel a lot more than this one, so there may not be that many older trucks with problems. Still, you might want to check with your dealer to see whether or not they recommend upgrading to help prevent a problem.

Removing the sulfur also removes parts of the fuel called aromatics that do a great job of lubricating your injection system, a characteristic called lubricity.

Lubricity is very important because only the upper parts of a unit injector or lower parts of an inline pump are lubricated by the engine oil. The fuel-handling internal parts, mainly a tiny plunger sliding up and down in a bore with a very tight fit, are lubricated by fuel alone. Injectors from 2002-2006 run at 26,000-30,000 psi, and 2007 injectors pump at 35,000 psi. Lubrication of a part that works that hard is real important for durability.

But all diesel fuel must pass the very same ASTM (American Society of Testing and Materials) standard for lubricity whether it is LSD or ULSD, and each batch is blended and tested individually by a petroleum distributor before it gets to you. Reports from both engine manufacturers and the American Petroleum Institute are positive when it comes to lubricity. There is no significant evidence of injectors failing because of lack of lube, so far.

While the API represents refiners, the organization also communicates with truckers in order to detect trouble and alert the oil companies of a problem in the field so it can be fixed before trouble gets out of hand. When they say there is no problem with lubricity, it’s likely they are correct.

If you have any fear about using ULSD in your vehicle, ask your dealer whether or not they have heard of trouble to make sure it will work without allowing your injectors to chew themselves up. If you’re still worried after that, you can always purchase a fuel additive made by a responsible manufacturer to put extra lubricity into your tank or buy premium fuel with extra lubricity. Just make sure that if running a 2007 truck with a DPF, the additive is approved for such use. Some contain too much sulfur for use with a DPF.

Cold weather blending
Cold weather blending could become an issue, so be careful. The EPA requires the refiners to make lots of ULSD No. 2, but there is no rule about how much ULSD No. 1 they have to produce. This means that if you are running a vehicle with a 2007 engine, blending in No. 1 or buying blended fuel that is not labeled ULSD is neither permitted by EPA regulations or a good thing to do for the DPF.

But David McKenna, product manager, marketing, Mack engines, says, “Gelling will be a problem handled by an additive program. You waste fuel blending in No. 1 anyway.”

The ASTM diesel fuel standard, in addition to guaranteeing lubricity, requires the fuel to be “additized” (have anti-gel additives blended in) so that it won’t gell at the prevailing wintertime temperature for the area where it is sold. The problem with relying on the standard alone is that you can get gelled up if the temperature is well below normal or if you travel to a colder area after buying the fuel.

For both these circumstances, you can just use one of the many anti-gel additives made by responsible additive manufacturers. If running a 2007 vehicle, just make sure the additive is approved for use with a 2007 vehicle with a DPF because those not approved may have too much sulfur content.

Will you put the wrong fuel in accidentally? That’s not likely, even though there won’t be any kind of special nozzle or tank fitting on 2007 vehicles.

“The fuel tanks and dispensers will be identified with a large, green label,” McKenna says.

Interestingly, some manufacturers claim that even a full tank of LSD put in by accident would increase emissions for a while but cause no permanent damage to the DPF, while others believe a high dose of LSD with its sulfur could cause damage. Those who are more concerned about LSD make clear that they will not repair damage caused by the sulfur under warranty. Plus, EPA regulations prohibit use of LSD in a truck with a DPF.

All the oil companies will be making mostly ULSD, since they are required to be able to produce 80 percent of on-road fuel as ULSD. Many fleets will be purchasing 2007 trucks and will need to use ULSD and the new CJ-4 oil to meet EPA guidelines while ensuring maximum engine life. Since fleets usually standardize on items like oil and fuel to simplify shop operations and driver training, as soon as a significant number of trucks with DPFs are sold, there will be a large shift to CJ-4 oil. As of Jan. 1, 2010, all on-highway diesel fuel must be ULSD, anyway.

All the engine oil refiners will be making CJ-4 because of the significant demand created by fleets purchasing trucks with the new engines and wanting to use the same oil in all their trucks. Shell has actually discontinued selling CI-4 except in bulk.

As of the end of October, production of LSD was hovering just above 23 percent of the total for on-highway diesel fuel. Al Mannato, the American Petroleum Institute’s fuels issues manager, says that, while API does not keep track of how many truckstops sell each fuel, truckers should find that availability generally mirrors the percentages of production. Oil refiners are constantly attempting to adjust their production to the market demand, so the production numbers actually depend on you the buyer.

Mannato claims there have been no major shortages of the new fuel, even though distributors’ tank trucks may sometimes have to travel farther to get it. Peak demand in the Corn Belt occurs around late fall because of all the fuel used to harvest crops, so supplies normally improve as winter sets in. So even if you’ve had occasional trouble finding the fuel you want, things should improve.

The Facts on ULSD
The EPA required that at least 80 percent of the on-highway diesel oil companies supply to their distributors be ULSD by June 1, 2006. All truckstops carrying ULSD, and that means most of them, needed to meet the specification by Oct. 15, 2006.

What’s different about this fuel? The crude oil that comes out of the ground naturally has sulfur in it. Refining crude into diesel fuel takes some of the sulfur out. The sulfur limit for the new fuel has dropped from the 500 parts per million allowed for the earlier fuel (low-sulfur diesel), used since 1992, to 15 parts per million.

The ULSD picks up some trace amounts of sulfur as it passes through the pipelines, so the refineries must change their processes enough to get the fuel down to about 8 parts per million to make sure the ultra-low stuff still meets the standard when it gets to the pump.

By Jan. 1, 2010, all on-highway diesel fuel must be ULSD.

Advantages of ULSD
When it comes to fuel, it’s like anything else: You get what you pay for. Your oil does many different things, one of which is to neutralize acids, just like Alka-Seltzer or Tums. Acid in your oil will do a very quick number on the bearings by softening up the metal, so running down the road makes them wear like mad.

You may have heard of an additive called TBN or “Total Base Number” in the oil. TBN provides alkalinity, which, while not damaging at all to the engine, is chemically the opposite of acid and neutralizes or cancels out its effect.

Most of the acid in the oil is sulfuric acid from the sulfur in the fuel. Bottom line: Removing so much sulfur from the fuel is good for the oil because there will be much less acid that the oil has to deal with.

Obviously, you’re going to run any vehicle with a DPF on ULSD no matter what unless you need some LSD to get you to the next truckstop. EPA regulations make it unlawful to use LSD in a truck with a DPF. So if a public official caught you misfueling a new truck, you might get fined.

But what if you are running a 2006 or earlier vehicle without a DPF? LSD will be around until Jan. 1, 2010, at least in limited quantities. Especially if you can get LSD regularly, and you are running an older vehicle, it would be perfectly OK to use it and would save you money.

In spite of the potential cost savings, there is a strong case for running ULSD anyway. When it comes to preventing wear and optimizing oil change intervals, running ULSD and the new CJ-4 oil is the hot setup.

The reason is that CJ-4 oil is much, much better for your engine, whether it’s old or new. However, it actually works better with ULSD than with LSD, and running the higher sulfur fuel may compromise its performance just a little.

The issue here is not what the fuel does to the engine, but what it does to the oil. The factor that limits when you need to change your oil varies depending upon how you operate and what kind of oil you use. However, if you use oil analysis, and one of the big factors in determining your change interval is TBN content, chances are pretty good that using ULSD might allow you to extend your oil changes, especially when you run an older vehicle. Older engines put less stress on the oil than 2007 engines.

CJ-4 oil is licensed by ASTM, the organization that approves engine oils only after they pass strict tests, to be backward compatible with CI-4. It will work even if you run LSD. However, most CJ-4 oils have a slightly reduced Total Base Number. TBN additives normally create ash. The new oil had to have less ash in it to extend the maintenance intervals for the DPF (See the July 2006 Truckers News for more information about DPFs). The reduction in TBN is very small and, with some oils, TBN may actually be the same, so it’s fine to use CJ-4. Jim McGeehan, Chevron’s global manager of diesel engine oil technology, headed the ASTM committee that determined what tests CJ-4 would need to pass. He suggests consulting with your engine manufacturer to determine your change interval if you want to switch to CJ-4 and go on using LSD. You may have to change a little more often.

The point is: CJ-4 is a super oil. It is so good that McGeehan said in our November 2006 issue that CJ-4 gives “verified longer wear in the field.” Chevron touts 38-50 percent less wear on various parts in comparing its CJ-4 with the earlier CI-4. Running CJ-4 and ULSD will guarantee you’ll be able to give your engine maximum protection while also getting the longest possible oil change intervals and, if you don’t use oil analysis, having the fewest worries about how long those intervals can be without causing unnecessary wear.

For More Information:
American Petroleum
(202) 682-8000

ExxonMobil Corp.
(800) 375-4328

Shell Oil
(713) 241-6161

(925) 842-1000

Travel Centers of America
(888) 982-5528

Petro Stopping Centers
(915) 779-4711

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