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As many of you know, a new passenger car engine oil category is under development, with the rather dull moniker of ILSAC GF-6. (We oil guys are not the best at giving catchy names to new and improved products.) Some of you are saying, Didnt we just get GF-5 approved? Well, yes, and that points to the ongoing quest to improve fuel economy, reduce emissions and add robustness to new engines.

The development of a new engine oil category is often a tortuous process where OEM needs, oil marketer needs and government desires all intersect to make a relatively straight-forward proposition under-go more twists and turns than a barrel of snakes.

For years now – going on 40 – the U.S. government has prodded things along, ordering vehicles to have greater corporate average fuel economy (CAFE) and reduced emissions. The CAFE limits were enacted in reaction to the oil crises of the 1970s and remained relatively unchanged until recently, when much higher targets were adopted. Todays CAFE regulations also incorporate emissions limits. Formerly these were treated separately, even though control of emissions impacted (negatively, I might add) on fuel economy. Thats not to say that separate regulations regarding emissions dont exist anymore. Theyre still there; its just that a new layer of rules has been added to the fuel economy mandates.

For their part, the OEMs have tackled fuel economy with great vigor and creativity. Tell me if you have seen a light-duty vehicle in the last 25 to 30 years that is carbureted? Fuel injection went from a specialty to standard in very short order, and the advent of on-board computers paved the way for vehicles to go from specific power of about 0.5 horsepower per cubic inch displacement to somewhere in the neighborhood of 1.5 hp – about triple. So the power of Chevys old 409 cu.in. (6.7 liter) engine can now be generated with only about 140 cubic inches. Amazing.

Of course, the trend to smaller-displacement engines has resulted in greater demands on lubricants. Gone are the days when an SAE 30 was the design standard for lubricating engines. Now OEMs look to SAE 5W-30 and even 0W-20 to achieve fuel economy gains while still providing wear protection.

All this time, the SAE J300 Engine Oil Viscosity Classification task force has been an integral part of the process. SAE J300 defines the limits for engine oil viscosity at low and high temperatures as well as low-and high-shear conditions. The standard includes low-temperature viscosity tests that measure the oils suitability for cold-weather starts and pumping, plus tests for kinematic viscosity and high-temperature/high-shear viscosity, which evaluate its ability to withstand conditions of shear and heat.

In recent years, the OEMs have recommended lower and lower viscosity oils in order to capture all of the friction-reducing benefits available. Currently, the best-selling grade of passenger car engine oil in the United States is SAE 5W-30, which replaced SAE 10W-30 about 20 years ago. In turn, SAE 10W-30 had replaced SAE 10W-40 in the late 1970s.

Looking ahead, we are now seeing a trend to SAE 0W-20 and SAE 0W-30, and soon a new viscosity grade will appear – SAE 16 – which will bring the internal friction number down even further. This latest addition to the SAE J300 standard has been successfully balloted in SAE Technical Committee 1, and now awaits a final blessing from the full SAE Fuels & Lubricants Division.

This novel grade will add a new wrinkle to the coming ILSAC GF-6 gasoline-fueled engine oil category. Until now, each GF category could be designed to be backwards compatible with previous categories. Simply stated, ILSAC GF-5 worked in engines calling for GF-4, GF-3, GF-2 and GF-1. However, GF-6 will not work that simple way.

Instead, there will be two versions of GF-6: GF-6A (backwards compatible) and GF-6B (not backwards compatible). GF-6As high-temperature/high-shear viscosity limit will have a floor of 2.6 mPa-sec – same as its predecessors – while GF-6Bs will be less than 2.6 mPa-sec. So GF-6B potentially could cause serious damage to older engines, thanks to this drop in HTHS viscosity.

Both GF-6 sub-types will include SAE 0W-20, 0W-30, 5W-20, 5W-30 and 10W-30 viscosity grade oils, and GF-6B will also make room for SAE 16. According to industry sources, the driving force behind SAE 16 are Japanese OEMs who believe that this very low viscosity grade will result in better fuel economy. North American OEMs have been more cautious in their assessments, but are watching closely to see how this plays out.

Youre probably asking yourself, why call it SAE 16? Wouldnt SAE 15 be more in keeping with traditional J300 nomenclature? The simple answer, and a good one, is that OEMs are concerned that consumers might mistake SAE 15W-40 for SAE 15, with disastrous results for performance, fuel economy and catalyst contamination. SAE 16 is different enough that no one should confuse it. (At least one can hope.)

To make sure that the new GF-6B category doesnt find its way into your grandmothers Dodge Dart, the American Petroleum Institute is looking for an entirely new designation for product labels. It will probably not be the GF-series starburst logo, but something else.

Over and above the viscosity issues, GF-6 proposals call for more stringent limits to be set on several engine sequence tests. These tests will apply to both the GF-6A and GF-6B categories, and use the same proposed limits.

Sequence VID, the fuel economy procedure, will in all likelihood become Sequence VIE given that a new GM engine has been put forth for the test. The new engine is very similar to the one now in use, and has already been compared to the current engine using the VID procedure and reference oils. The results show that the new engine may be slightly mild – which is shorthand for less severe and giving somewhat improved results. The limits proposed for GF-6 are almost double those of GF-5 in terms of percent fuel savings, sure to be a major challenge for oil formulators.

The Sequence VG sludge and varnish test is also up for modification. Ford, which supplies the current test engine, has offered a 2-liter turbocharged engine to replace the tests current engine. Details are unknown, but the proposed limits call for better varnish and sludge control.

The current Sequence IVA valve-train wear test, sponsored by Toyota, is apparently still good to go. Toyota hasnt offered a new engine or procedure, so there is no activity in this area. The same can be said for the Sequence VIII bearing corrosion test. Some may recognize this test by its older designation, the L-38. The modern version uses the same procedure but is run with unleaded fuel.

That brings us to the Sequence IIIG wear and oil thickening test. Limits proposed for GF-6 are more stringent on oxidation control, as measured by viscosity increase, and on piston deposits. The tests wear component has not changed. There will be a new engine for this test, but its not yet fully defined.

Related measurements (not technically part of the Sequence IIIG test, but run afterward) evaluate the condition of used oil. These include the Aged Oil Low Temperature Viscosity test and the Phosphorus Volatility test. Both of these tests need used oil, for which the Sequence IIIG test has been the logical source. With the new IIIG procedure and hardware, its unknown whether used oils will continue to be collected for these tests.

There is also a question about who will maintain the Sequence IIIG successor test, and how. At this writing, General Motors, which sponsors the IIIG test, has offered a new test engine but will not support it as an ASTM procedure. In the past, all engine tests were approved and monitored by ASTM, and so will the other GF-6 procedures. The lubricants industry could take GMs new wear and oxidation test to ASTM on its own and support it in that fashion. But GM is concerned that it will lose the freedom it needs to support its proprietary Dexos engine oil specifications. In effect, GM wants the ability to update the method and/or limits on its own, without waiting for ASTM to process any needed changes.

Industry sources tell me that Chrysler has made an offer of an oxidation test, but no details are available about what it would entail – except that it is an engine test. I understand that Chrysler would agree to ASTM management of the test.

Two other engine tests have been proposed for the category. One is a timing chain wear test, the other an oil aeration test. There are no details on the timing chain test, but the aeration test that is being developed for PC-11 heavy-duty oils seems like it would fill the bill very well.

Bench test requirements are essentially the same, although there are some tweaks that might come to pass such as shear stability limits for SAE XW-20 grades which are proposed to be 6.1 mm2/s. In addition, a low speed preignition test procedure is being proposed.

Its also noteworthy that in the effort to launch GF-6, the auto and oil industries will adopt a process similar to that of the Diesel Engine Oil Advisory Panel (which is responsible for PC-11, the new heavy-duty oil). Directed now by the Auto-Oil Advisory Panel, co-chaired by Terry Kowalski of Toyota and Luc Girard of Petro-Canada, this process is intended to replace the more rigid ILSAC/Oil Committee system outlined in Appendix C of API document 1509, the Engine Oil Licensing & Certification System. I think this is a great step forward in developing new engine oil categories.

The American Chemistry Council (ACC) has proposed a revision to the first licensing date for GF-6 oils, to January 2016, so as to accommodate the expected logjam that will occur when both GF-6 and PC-11 come on line at essentially the same time. ACC recommended earlier that PC-11 begin licensing July 2016.

To sum up: Well have two new engine oil categories with extensive engine test changes, new viscosity targets, new names for some grades with an accompanying loss of backwards compatibility, both to come on line in 2016.

Did I hear anybody say no sweat, we can do this?

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