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Its the beginning of a new year, so lets take a look at what might happen to automotive engine oils in the next few years. In order to do that, we need to look at the forces driving original equipment manufacturers, and how they affect engine choices and lubricant requirements.

So, what drives OEMs? Number one is profitability. No major OEM in North America is doing well financially at this point. Beset by a weakening dollar, high crude oil prices, potential recession, flagging sales and shrinking margins, OEMs are in a pickle.

Number two is the push to boost fuel economy and cut emissions, which is driven by government legislation. Theres nothing new here. The federal and some state governments seem to have the idea that simply by legislating it, improved fuel economy will magically appear. One recent proposal is for corporate average fuel economy to reach 35 mpg by the year 2020.

Number three is customers desire to have a roomy, comfortable vehicle that gets good mileage and can rapidly accelerate from a stop sign! Not a very compatible set of desires, but thats what they want.

How then, might OEMs respond to the challenge? A number of automakers (especially the Asian OEMs) are promoting hybrids – some with improvements. For instance, Toyota is adding a plug-in version that allows owners to charge their batteries overnight and then drive up to six miles before needing to engage the gasoline engine. Most are running as demonstration programs because of high manufacturing costs. General Motors has released 200 Chevrolet Volt prototypes; these are battery-powered vehicles with a small gasoline engine included to charge the batteries on the fly but not drive the wheels. Honda, Hyundai and GM also are working to demonstrate fuel cell technology based on hydrogen fuel. All of these are laudable but dont make much of a dent in the energy equation in the short term.

Most likely then, the OEMs will continue to utilize existing engine technologies. That means spark ignition (gasoline) and compression ignition (diesel) engines. Of course there are hybrids, but these are actually a conventional engine in combination with a big battery (or batteries) and an inline battery charger.

The bigger challenge is what fuel will be used – and how that affects engine oil formulations.

The Buzz in Gasoline

For gasoline engines the talk is all about biofuels, specifically ethanol. When Dario Franchitti won the 2007 running of the Indianapolis 500, he was the first to win using 100 percent ethanol fuel. His 670-horsepower Honda engine performed flawlessly, as did all of the other engines (all Hondas) in the race. Now NASCAR is considering a green series of races. No fuel selection is mentioned here, but ethanol would be a good bet.

Ethanol is what we used to call grain alcohol. Its the ingredient in beverages that gives us the buzz and can get us into a lot of trouble if we are consuming it and trying to drive our vehicles. (Dont do it!)

Current gasoline blends may contain up to 10 percent ethanol to minimize emissions, especially in certain non-attainment areas at certain times of the year. Congress has proposed giving ethanol producers an added incentive by extending tax credits and tariffs until 2012 while requiring 7.5 billion gallons of ethanol for fuel purposes. That sounds like a lot but only displaces 5 billion gallons of gasoline due to the fact that a gallon of ethanol has only two-thirds of the energy content of a gallon of gasoline.

Since spark-ignition engines need a volatile fuel to combust properly, there is a definite limit to the types and/or amounts of non-traditional components that can be used. That means you cant mix soybean oil at any appreciable amount in gasoline and expect to have a decent fuel.

There is also the small matter of a suitable distribution system to get alternative fuels to market. Changing to any new composition fuel requires that pipelines, bulk transports and service stations be supplied with appropriate tankage and lines. There are hoses and seals that might not be compatible with new fuels, which mean refitting the system at a staggering cost!

Next, you need to recognize that Indy and NASCAR engines arent like anything youd find on the road. Nor are the engine oils used by these cars like the ones you and I can buy at our local auto parts stores. Racing engines and oils are designed to go all-out for 500 miles. The oil is long on antiwear, antioxidant, dispersant and emulsifier to control fuel dilution. There is also a good slug of antifoam and possibly some friction modifier to capture a few morsels of fuel economy. Since these oils are multi-viscosity, there is some polymer but not a lot.

For the family car, current 10 percent ethanol blends dont present too many problems. Existing API SM/ILSAC GF-4 engine oils do just fine.

On the other hand, E85 (85 percent ethanol), which has been proposed as a longer-term solution to energy needs, will present some big problems for current oils. Rust due to water condensation and emulsification with ethanol in the blow-by gases is a big issue. Brazil encountered this problem when it adopted E85 fuel several years ago. The rust can be controlled, but formulation changes will be necessary. The most notable will be the inclusion of some really strong anti-rust materials, as well as emulsifiers to control fuel dilution. The rest of the chemistry will be pretty standard.

One question is this: How will fuel economy be measured in an engine fueled by E85? The reduction in energy content will be evident in lower fuel economy claims. Remember, fuel economy certification has to be done with widely available, cost-competitive engine oils. Fuel is also defined.

Another Alcohol Option

Indy cars used to run on methanol, or wood alcohol. Its not so great for energy and very toxic. As a fuel, methanol has 15% less energy content than ethanol, and is even more of a problem when water is present. It will separate from fuel blends and cause no end of headaches in the crankcase as blowby. The same fixes needed for ethanol will be required with methanol – only more and of different composition. (And by the way, when methanol catches fire you cannot see the flames. Thats why there is a crew member in the pits at races who does nothing other than hose off anyone who looks uncomfortable or who is rolling around on the ground!)

Other potential sources of fuels are gaseous products such as propane or natural gas. Historically, there have been many conversion kits that allow an engine to run on these fuels. Many agricultural applications using converted automobile engines are known. Both propane and natural gas are excellent fuels but present some difficulties in the engine that are not totally addressed by current engine oils. They burn very cleanly, so there is little or no contamination that gets into the crankcase as blowby. However, they do operate at higher temperatures so there is a premium on antioxidant performance by the engine oil. Oils for stationary natural gas engines have been around for a long time in industrial applications – pipelines, offshore platforms – so the technology is available to create engine oils for gaseous fueled engines.

Future Diesels

For diesel engines, too, biofuels are all the rage. Most heavy-duty engine builders have issued bulletins or specifications for the use of biodiesel. Depending on what part of the world youre in, the source of the biodiesel varies (see table, above). Its important to understand that biodiesel is actually a range of products containing varying levels of the materials shown in the table. B100 is the pure material. Most diesel manufacturers are recommending a blend of B100 with petroleum based fuel. Conservative recommendations are for B5 – 5 percent pure biodiesel plus 95 percent conventional fuel – while B20 has been accepted with little change in operations.

Pure B100 is another story. The properties of B100 are different from conventional diesel fuel. As a result, when B100 is used, there is a much greater tendency for fuel to find its way into the crankcase, creating a much

larger amount of fuel dilution. There is also a greater likelihood of gellation at low temperatures, due to the excess fuel dilution. Corrosion is also an issue. Historically, there have been problems with methyl esters in engine oil attacking certain bearing materials, primarily copper-lead. To date, only one OEM has approved the use of B100 in its engines.

Formulating engine oils for biodiesel depends totally on the level of biodiesel in the fuel. B100 will require much stronger corrosion protection, special pour point depressants, additional antifoam, and probably some way to emulsify water since that will create even more problems in the crankcase. B5 will not require any changes from current chemistries. B20 is on the cusp formulationwise; it could need some additional pour point depressant and possibly more emulsifier.

New diesel emissions requirements will undoubtedly play a part in what future engine oil formulations look like. For 2007, over-the-road engines must use 15 ppm ultralow- sulfur diesel fuel (ULSD). Particulate emissions are more carefully controlled and the addition of particulate traps on exhaust systems has definitely impacted engine oil formulations.

These issues were behind the API CJ-4 diesel engine oil specification, which set maximum limits of 1 percent ash, 0.12 percent phosphorus and 0.4 percent sulfur. Market acceptance has been slow, however, due to concerns about reduced detergency. Some operators feel that they can live with the older API CI-4 PLUS formulations and refresh the particulate traps more often. There are some who say that the concerns about particulates are not valid. At any rate, todays formulations for diesel engine oils will remain in place for some time, unless biodiesel at high levels (B20 or greater) becomes common. Then there will be another flurry of development work.

For passenger car diesel applications, many of the same rules apply. ULSD is available at most pumps but finding a biodiesel blend is more difficult – except, as you might expect, in the Midwest where these products are more popular.

The next few years will be significant for automotive engine oils. The introduction of all-electric and fuel cell powered models will mean a reduction in traditional engine oil products. How fast that goes – and how far – are yet to be determined.

As always, it seems as though we are going into or out of some change almost all the time.

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