Regulations Specs & Testing

GF-5: Bearing Down Fast


Almost four years ago, in December 2004, automakers asked that a new gasoline-fueled engine oil specification, called GF-5, be ready for market by July 2009.

That schedule was overly ambitious, but GF-5 at last is taking shape as a fuel-economizing, emissions-system-protecting, cleaner and more robust engine oil. Most expect that it will be ready for approval late next year, and take its place on store shelves by summer 2010, in time for the 2011 model year.

GF-5 is intended to deliver 0.5 percent better fuel economy than current GF-4 products, explained Bob Olree of General Motors, chairman of the ILSAC/Oil Committee that is creating GF-5. The ILSAC side of the committee includes North American and Japanese auto manufacturers; the Oil side includes engine oil and additive companies. And it may not sound like much, but on a national scale, 0.5 percent fuel economy is worth pursuing. Additive company Lubrizol Corp. points out that over GF-5s expected five-year life and across the U.S. fleet, the savings could amount to more than 650 million gallons of gasoline.

Besides greater fuel economy, Olree told LubesnGreases, the new oil will also require greater sludge and deposit control, especially for turbochargers; more retention of the antiwear agent phosphorus so it cant damage emissions systems; and tests for elastomer seal compatibility and oil aeration.

The showpiece of GF-5 is a new engine test for the oils fuel economy contribution, the Sequence VID (six-D), which despite years of work is not yet nailed down. It uses a modern GM 3.6-liter V6 engine in place of an older Ford engine currently used to test fuel economy. Created by a consortium of 10 auto and oil companies, the new test will help the auto companies reach their federally mandated fuel economy average of 35 mpg by 2020. It responds particularly well to high levels of friction modifiers – but more about that later.

Olree acknowledged that the VID test had its skeptics, some of whom felt the new test did not correlate to actual field experience. When you try to measure fuel economy in the field, you can only discern small changes, he commented. All the benefits from the oil are hidden by the rest of the changes that are going on – tires, temperature, braking drag, driver differences. There are too many variables. That doesnt mean the improvement isnt there, but it does make it hard to measure.

We found that when you strip the rest of the variables away and just have the engine there, just the VID, it can separate the oil effects much better than on the whole vehicle.

The VID now is moving towards a round of test runs to prove it can precisely measure this fuel economy benefit. A 44-test precision matrix will be managed by ASTMs Passenger Car Engine Oil Classification Panel, and must begin soon, Olree said in early October.

A month ago I would have thought we were being overly optimistic, because our original plan was to have the precision matrix take place from Oct. 1 to Nov. 30, he said. However, its looking now like it should be finished by early January, so thats roughly a month behind. So Id say were fairly well on schedule.

Since each VID engine test run costs over $15,000, theres also the question of paying for the matrix. Classification Panel Chairman Thom Smith, of Valvoline, said the funding has been worked out in principle among the American Petroleum Institute, the American Chemistry Council, the Japan Automobile Manufacturers Association and the Alliance of Automobile Manufacturers. Two laboratories with two VID test stands each, Intertek and Southwest Research Institute, will perform the tests.

With 44 tests in the matrix, thats 11 tests per stand, Smith calculated. Once the matrix starts, we expect them to do at best about one test per week per stand, so thats about 11 weeks in all.

As of early October, the legal contract for the VID matrix was not signed yet. But it could be by the time this issue reaches readers, said Kevin Ferrick of API. Once the memorandum of agreement is signed, ASTM will manage the fund and make the payments for the tests, he said. So the sooner we can start, the sooner were done. The 44 runs will cost under $700,000 and include both precision tests and the tests needed to develop Base Oil Interchange and Viscosity Grade Read-Across guidelines for oil formulators.

Where the test will steer GF-5 formulations is still unknown, though. It is too early to definitely state what the Sequence VID responds to, as the test, and how it will be used, is not final, pointed out Steve Haffner of additive company and VID con-sortium member Infineum. As of today, given the suggested weightings for the test, it is biased towards viscometric responses and its appetite for friction modifiers is still to be determined. It could require a rebalance of the friction-modification system currently used in GF-4 products.

Glenn Mazzamaro, of consortium member R.T. Vanderbilt Co., said the VID responds very well to friction modifiers, including those containing molybdenum which have been boosting fuel economy by up to 2 percent in Japan for many years. In the past, North American fuel economy has been met with less-costly alternatives, organic friction modifiers, he said. They are less expensive, but also less effective. What gets used will depend on the limits and requirements of the VID test.

There are three or four ways to formulate to get better fuel economy, Mazzamaro went on. One is to use organic friction modifiers, which already are in GF-4 oils. Second is to use nonconventional base stocks, with improved viscometrics, such as Group III or PAO. A third is to add molybdenum. And the fourth would be to rebalance the entire formulation – take out the additives that are detrimental to fuel economy, such as ZDDP and detergents, and replace them with others. The difficulty is to protect against wear and deposits, because thats what the ZDDP and detergents are needed for.

R.T. Vanderbilts own interest lies with molybdenum, he allowed. The formulation space is very competitive, and there may be other organic friction modifiers that could be used, too. But now were already squeezing out about as much performance as we can based on organic friction modifiers and lighter viscosity grades. Well have to think harder about moly and other options.

Molybdenums biggest challenges are its price – which has quintupled to nearly $30 a pound in recent years – and its availability. New mines are coming that may change this picture, but cost will remain a concern as long as engine oils are so price sensitive. At current prices, estimates are that high doses of moly could add 20 to 30 cents per gallon to the oils cost, so its not insignificant.

Also not insignificant is another proposed test for GF-5, the TEOST 33C bench test to measure high-temperature deposit control. This test may be heading for a collision with the VID, because the same friction-modifying additives that help boost fuel economy seem to do poorly on this coking deposit test.

With its popular PT Cruiser depending on turbochargers, Chrysler is championing the TEOST 33C for inclusion in GF-5. The test is familiar to many from the earlier GF-2 specification, where it had a limit of 60 mg maximum deposits. Most oils today could meet that with ease – but for GF-5 Chrysler wants to slash the limit to 25 mg. The automaker said it tested many GF-4 oils, and 85 percent of them passed this proposed TEOST 33C limit – meaning 15 percent didnt.

Chrysler has promised to supply data to justify the tests inclusion and limits, and Ford and others also seem to favor the test, since turbochargers will be a larger part of powertrain offerings in the future. However, Japanese OEMs dislike the tests negative appetite for molybdenum.

Nor are oil and additive companies convinced that the test is needed, saying there has been no evidence it will protect turbochargers. On the oil/additive side, Mazzamaro said, few participants want to see another test, especially one that is not proven to the extent the oil side would like, as to how it relates to field performance.

Infineums Haffner also questions whether the TEOST 33C is meaningful in addressing turbocharger deposits. JAMA has stated that oils with high levels of molybdenum-containing compounds have fuel economy benefits and show no detriment in their turbocharger operations, he said. We are awaiting data from Chrysler that shows GF-4 oils or proposed GF-5 oils with high levels of molybdenum cause a problem in their specific hardware configuration. There is no easy solution or one that will be delivered in time for GF-5 such as a turbocharger test of some type.

Chrysler, or any OEM that has evidence that the TEOST 33C will protect their specific engines, can utilize that test in their own OEM specifications, he went on to suggest, thereby not restricting others from using these high-moly oils which can bring a significant fuel economy benefit.

Some compromise regarding the VID and TEOST 33C clash is probably going to be needed, but it must come soon. Once the VID matrix is done, the additives industry is supposed to have six months – a technology demonstration period – to try out the results and optimize their chemistries.

The whole spec needs to be approved by Sept. 1, 2009, reminded Vanderbilts Mazzamaro, and auto companies consider that deadline to be firm. So if the VID precision matrix falls any further behind, it will eat into the technology demonstration period. Having less time will make it more difficult for the big additive companies to put their packages together. Usually they want to work with the tests and see what their technology can do, before going out with the package to their customers, the engine oil companies, he explained.

As you know, tests and the limits of parameters of those tests may have conflicting appetites, said Haffner. The technology demonstration period allows the additive companies to test prototype formulations in the finalized tests to be included in the GF-5 specification, and balance their additive packages to deliver robust products. Base stock selection also plays a key role in oil performance, and the combined effect of various base stocks and additive chemistries must be addressed in the key definitive tests during this time period.

All that takes time. And since the test limits arent set yet, it can also be frustrating. Until the final specification is defined, it is hard to know the final appetite of the VID engine test, said Haffner. Any new or exotic additives tar-geted for GF-5 applications should already be embedded in the formulation strategy for an additive supplier, due to the time it takes to bring truly new components into the market. Even minor reformulation can lead to significant investment that will add costs to GF-5 products. Once the VID and the tests limit are better defined, we can make our final assessment.

Finally, in third-quarter 2009, the auto, oil and additive sides must sit down to negotiate the final tests and limits for the specification. Once theyre approved, APIs Lubricants Committee ideally will wait nine months before it issues the first GF-5 licenses. This will give all candidate oils a fair chance to secure time on test stands and get ready for market, APIs Ferrick stated. That would put first licensing at around July 2010.

Bob Olree, however, will have to cheer it from the sidelines: He was due to retire from GM on Oct. 31. Tracey King of Chrysler is now ILSAC/Oils chairperson, and will wield the gavel at the groups next meeting in December.

Olree said he regrets not being in on the upcoming negotiations over test limits. The limits put real teeth into the oil specification, and are where the auto companies will find out if GF-5 gives them what they need.

I believe the ILSAC/Oil process is working, he said. Maybe were going to be a bit late, but not much. Im satisfied that everything is on track, and well not go past the third quarter of 2009 for the approval.

And will GF-5 deliver more value to oil and additive companies, as well, in return for their years of effort and investment? With a nod to the close to 250 million vehicles on the road today being lubricated by current GF-4 oils, Haffner expressed doubts.

At the current time it does not appear that the marketplace will value any substantial innovation in the conventional passenger car engine oil market, to make significant changes cost effective to the customer and to allow additive companies and marketers to make a reasonable return on their investments, he opined.