ULV Oils - How to Contribute & Enable Fuel Economy

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So after being away for several weeks - I came back to the board and found a couple of interesting threads, with some comments about how new engine oils (meaning GF-6B and the low visc HDDEO that will come with FA-4) will backfire because of durability concerns. This isn't anything new - every time the trend has been toward lower and lower viscosity there have been concerns about durability. I've made it pretty clear in previous threads that the new ULV (ultra-low viscosity) oils will be held to the same durability standards as the existing 5W30's etc - and in some cases the durability requirements may even be more stringent.I thought it might be nice to share some information I learned at a recent industry meeting on ULV oils which opened up a whole new perspective for me: Consider this image (source: GF-6.com) It shows that CAFE targets in the next 10 years will go to almost double the current standard. Essentially since the late 70's we've seen a roughly 40% increase in fuel economy - so 30 years to get from 20 mpg to 27 mpg and about a 30% increase in the last 5 years since 2011. The current 2025 target puts the requirement to an additional 95% increase in 10 short years. That's a huge amount and the OEM's are leaving no stone unturned. This is where my perspective changed a little. We all know that thinner oils can directly contribute to fuel economy. It's fairly well documented that lower HTHS (with the right additives to control wear) can directly impact the fuel economy in standardized tests. We see that in the Sequence VID test as well as in other on-road tests for fuel economy improvements. So the fact that ULV lubricants directly contribute to fuel economy should come as no surprise to anyone. However there is a great deal of debate to whether this matters to the average user. I think many BITOG enthusiasts would say it doesn't and that thinner oils won't produce a significant ROI especially if the durability of the engine is sacrificed in any way. But what about using engine oil to enable new types technologies that are by their very nature more fuel efficient? What if instead of being concerned about the fractions of a percent that a lubricant may directly contribute - we were more concerned about bringing together the tribological and rheological properties of advanced ULV fluids with new engine materials, higher power densities, increased turbo-charging, smaller displacements, more complex and efficient transmissions, axles and other parts of the powertrain? What if by their very nature a highly engineered ULV fluid allows the use of more complex technology than before because it is specifically targeted to this new tech and no longer is held to be compatible with engines that were designed 50 years ago. Here is an example - Turbochargers are known to be tough on oil - specifically they can shear oils out of grade which then risks the durability because the minimum oil film thickness may be sacrificed. Typically the response has been to avoid ULV oils and revert to a higher HTHS or higher viscosity fluid. BUT What if the need for a heavier viscosity grade was eliminated by the use of a more robust additive layer where the oil is more about the chemistry (additive package) then it is about the carrier (base oil viscosity). All of the sudden you can turbo-charge with higher pressures because the chemical protective layers are what protects the bearings and the base oil just makes sure the chemistry gets to the right place. If that is happening then you want the base oil to be as thin as possible to reduce any kind of drag because it no longer required to maintain any kind of durability. crzy crzy shocked2 What I know you think I'm crazy right! Consider this quote about GDI engines:
Quote:
Power densities (Average HP/liter) have increased rather steadily as engine hardware has advanced. With GDI engines now beginning to dominate the market, Lubrizol believes that engine oil formulation has reached a tipping point in which new performance demands will require higher concentrations of specific additive components when compared to ILSAC GF-5. Set for licensing in Q1 2018, ILSAC’s GF-6 engine oil specification aims to better suit GDI engine designs by improving lubricant robustness, increasing cleanliness and durability, and producing higher fuel economy throughout the entire oil change interval. Among the many changes in the performance requirements of engine oils from GF-5 to GF-6 (all of which are proposed), the most notable will be improved viscosity, deposit, and oxidation control, as well as very significant increases in fuel economy improvement (FEI). Protecting against the occurrence of engine oil-caused, low-speed pre-ignition (LSPI), along with increased wear protection for various engine components such as timing chains and valve trains, will also be the primary focus of GF-6 lubricants.
The fact that the new reality where the additive package becomes the primary source of durability and the base oil becomes simply a carrier is also evidenced by the fact that treat rates are now going up, and base oil quality (volatility, oxidation resistance, etc) are the focus of most of the conversations around GF-6. For people who pay attention to ATF (honestly I don't know anyone except maybe Molakule who really does) this battle has been progressing for years. Dexron VI and Mercon LV fluids are highly engineered ULV fluids that enable new types of technologies for transmissions. CVT's and DCT's also require special fluids to enable their technologies. Why would we be surprised to see engine oils following the same pattern? So for all you naysayers saying that these ULV lubes are probably going to backfire - I'd be willing to bet you are wrong. What is happening instead is a whole new range of engineering possibilities are opening up because the new oils enable these technologies rather than continuing to rely on viscosity as the primary defense against wear. When I came to the realization that thinner oils aren't about cold-flow or tiny gains in fuel economy at start up (which is what most of the threads devolve into when we talk about thick vs thin), it completely changed my perspective. This is why certain OEM's like HONDA and TOYOTA are so keen on 0W8, 0W12 and 0W16 - because they have abandoned the thought that viscosity is required for durability and are more focused on what a highly engineered fluid can do - and what new technology can be developed when we throw all the old design constraints out the window. At the presentation I attended, the topic came up about just how thin can we go and how far can developments in the molecules really do enable new engineering designs. Lubrizol seems highly confident that they can build new additive packages that can deliver improved performance on every level, durability included.
 
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So for all you naysayers saying that these ULV lubes are probably going to backfire - I'd be willing to bet you are wrong. What is happening instead is a whole new range of engineering possibilities are opening up because the new oils enable these technologies rather than continuing to rely on viscosity as the primary defense against wear.
Agree. Each time viscosity is lowered, this is a concern, but it's never been an issue. Engines are lasting longer than ever due to all the changes you mentioned above. Good post. smile
 
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Interesting post. My take is that it's only logical that in the future the oil will be designed around the hardware as you're seeing this now with GF-6 and direct injection. It will only be more prevalent in the future. Although this board sometimes seems fixated on oil as somehow being a main contributor to MPG and related CAFE standards, the reality is new engine materials, different transmission / powertrain technologies are the only way to reach the coming standards...so the paradigm shift is going to eventually leave behind a lot of previously sacrosanct mentalities. To me, it's not very hard to see the potential of "thick vs. thin" eventually becoming "irrelevant" based on technological changes.
 

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I also got the impression that the new ULV oils will be co-designed with OEM's - so that means a lot more Genuine fluids. I've also noticed more and more OEM's creating their own registration for fluids (kind-of like the dexos1 spec) - I'm thinking BMW which now has a registration for some of the LL fluids, cummins on the HDDEO side etc.
 
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Won't apply to the used car market for close to a generation. Cars and trucks are lasting longer and the public expects that trend to continue due to the high price of acquisition. So all the millions of existing vehicle will require existing lubes and the move to HM's at that... The new lubes and the associated technologies will have to be amortized over time - how short? The shorter, the higher the individual/unit price. Are we going to have $150 oil changes once a year? We already have $5/qt oil for run of the mill applications and $18/L for extreme performance applications (Motul). So where does the general public say enough already... What are the re-refining costs associated with these "new chemistry's"? Will this stuff be more toxic than existing oils? There is more than one way to get a black eye here frown
 
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Thanks Solarent, I stated (and was poo-pooed by the thin crowd) quite some time ago that they were heading more down boundary/mixed lubrication and adjusting for that than relying on hydrodynamics.
 
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Originally Posted By: Tuffy1760
Hydrodynamics... love that word...
Yep, so do I. My engineering career has been spent trying to keep things in hydrodynamic regions for essentially infinite life (200-300,000 hours of operation)...dropping into additive controlled regimes means living with an "acceptable" amount of wear.
 
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Why can't you have the super duper additive package and not worry about the ULV? What is the advantage of ULV specifically? I think CAFE needs to be revamped and credits should be minimized for any design that will be out of the OEMs control once the car hits the street. Credits for E85, thin oil etc are ridiculous because the OEM doesn't control their use, the consumer does. If OEMs didn't get CAFE credits for ULV would they still develop it? It doesn't change the mpg on the sticker so I think they wouldn't put so much effort.
 
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Originally Posted By: Nate1979
If OEMs didn't get CAFE credits for ULV would they still develop it?
I'm sure they would to a point, but maybe not as quickly to the extent that we see.
 

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Originally Posted By: Shannow
Originally Posted By: Tuffy1760
Hydrodynamics... love that word...
Yep, so do I. My engineering career has been spent trying to keep things in hydrodynamic regions for essentially infinite life (200-300,000 hours of operation)...dropping into additive controlled regimes means living with an "acceptable" amount of wear.
I think the new chemical controlled wear regime doesn't really fall into our classic interpretation of boundary/mixed (or maybe it does I'm not really sure...) If the oil film is depositing an elastic layer which forms a semi-fluid protective chemical film (a eutectic system) and the compression resistance of the layer is such that it keeps the asperities separated, combined with the elasticity of the bearing materials - ends us in the elasto-hydrodynamic regime. That would mean we don't have to live with an "acceptable" amount of wear because if the fluid-film is forming properly then there would be no abrasive or adhesive wear to the metal. Of course we could talk about other types of wear - like fatigue...and this strategy didn't talk at all about the cooling capacity of the lubricant relative to viscosity which could be a whole additional conversation.
 
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Solarent, nice piece. Yes the conventional thinking that lighter oils will automatically lead to less engine running time in full hydrodynamic mode and more in mixed or boundary has always been flawed. Obviously you still have to maintain primarily hydrodynamic lubrication to achieve any fuel economy gains but the trick is how to minimize oil drag in the process; namely, reduce excess viscosity but still maintain the required minimum oil film thickness (MOFT). Even with conventional oil formulations, auto engineers in recent years have relied on electronic safety management controls to maintain the required MOFT if the oil gets too hot and therefore thin under extreme usage. Improved oil formulations that further control viscosity change with temperature (ultra high viscosity index oils) have the dual benefit of reducing oil drag on start-up and during warm-up while also reducing the rate of viscosity loss at high operating temp's. In fact in F1 racing, motor oil (likely a polymer additive) has been developed that actually stops and even reverses viscosity loss at a certain high temperature. If and when this motor oil technology works it's way into main stream formulations (cost is always a limiting factor plus keeping a racing advantage from competitors as long as possible) I don't know but what's inevitable is technological lubricant improvement. So when a manufacturer specifies a lighter oil grade, especially an OEM approved motor oil, I for one am confident that they have more than done their homework in maintaining minimized engine wear... http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3753781/1
 
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Originally Posted By: Solarent
I think the new chemical controlled wear regime doesn't really fall into our classic interpretation of boundary/mixed (or maybe it does I'm not really sure...) If the oil film is depositing an elastic layer which forms a semi-fluid protective chemical film (a eutectic system) and the compression resistance of the layer is such that it keeps the asperities separated, combined with the elasticity of the bearing materials - ends us in the elasto-hydrodynamic regime. That would mean we don't have to live with an "acceptable" amount of wear because if the fluid-film is forming properly then there would be no abrasive or adhesive wear to the metal.
Regardless of the surface active stuff, the viscosity is what determines the friction and Oil Film thickness on the RHS of the Stribeck curve. It's modification of the left hand side (EHD, MIxed, Boundary), so I still think that those terms apply here. e.g. I think this preso describes what we are talking about. Pushing the left hand side of the stribeck around through chemical means. http://www.sae.org/events/pfs/presentations/2005spikes.pdf (Some years ago, I had dinner with aCstrol chemist who worked on "magnatec", and described that while doing back to backs the magnatec effect carried through into the reference oil...can only happen if it's a surface effect like slide 22 onwards).
 
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