Do you think that's "thick" oil? Think again!

[Gokhan]

Well, OVERKILL, of course, you can't compare apples and oranges. You need to compare within the synthetic or conventional lines. Regarding M1 0W-40, I doubt there is much PAO in it these days. It's mainly Group III+ and they wanted to have it entirely GTL (which is Group III++) in the future.

Regardless, SAE viscosity is SAE viscosity. You can't count on getting a much thicker base oil for the same SAE viscosity grade by opting for a synthetic or a more fancy synthetic. Type of base oil influences NOACK, but the CCS viscosity, which gives you an idea of how thick the base oil is, is determined by the SAE viscosity grade.

 

[Gokhan]

Originally Posted By: turnbowm
So, 10W30 over 5W30 for lower timing chain wear but 5W30 over 10W30 for lower start-up wear?

Well, in California, you won't feel much difference between 5W-30 and 10W-30 in terms of oil flow.

 

[Gokhan]

Originally Posted By: littleant
Gokhan thanks for your post. Good read. A question if I can. My interest is with timing chains (3 in a 2010 mountaineer 4.0). Is it more important to get oil to the chains at startup (5w30) or when running (10w30) Summer/Winter. Ford specs 5w30 and the one engine that never changed to 5w20. I use QSUD 5w30. At these weights does it even matter?

You live in Vermont. I'm guessing it gets pretty cold there in the winters. My manual says don't use 10W-30 below -10 F (-23 C). Of course, you may have a partially heated garage. You may not get much oil anywhere when it gets colder than that.

I don't know how cold you can go before startup wear due to viscosity becomes an issue. Some Canadians use 10W-30 and you can ask if any of them have an oil-pressure gauge and what they think about it.

 

[ZeeOSix]

Originally Posted By: Gokhan
I don't know how cold you can go before startup wear due to viscosity becomes an issue. Some Canadians use 10W-30 and you can ask if any of them have an oil-pressure gauge and what they think about it.


If it was 10W-30 at -35C (-31F), which they showed in the video posted by Shannow above, the oil pressure would probably be pegged because the oil pump would be in pressure relief for quite some time. Notice how bad those cam lobes looked on that cold start test car? Obviously it was taking some abuse.

 

[Gokhan]

I should say that this knowledge of the importance of base-oil viscosity vs. VII-improved viscosity is brand-new to me! I'm very glad that Shannow pointed out to the Nissan paper and I ran into it. Of course, it's only one paper, but it makes you think again about oil viscosity!

Long time ago I always wondered why my manual would recommend 10W-30 but not 5W-30, except in extremely cold weather. I just couldn't find an answer anywhere. Later I learned about oil shear (viscosity loss) and 5W-30 having more permanent oil shear than 10W-30 because it had more VII. So, this seemed to be the answer. However, now that I learned about the importance of the base-oil viscosity, I think that the real answer wasn't oil shear, but base-oil viscosity!

Now, you can say that it's an outdated 1985 manual. However, this is from the 2018 Kia Stinger manual:

For their TGDI engine, they recommend 5W-30, 10W-30, and 5W-40, but no 0W-40! Most people who read that thread thought it could be an oversight by Kia, but now, I think that it's because of the base-oil viscosity and the fact that these TGDI engines have timing-chain wear problems.

Timing chain isn't the only place where base-oil viscosity could be important. The valvetrain and parts of rings and cylinder linings also operate in similar lubrication regimes (boundary and mixed lubrication regimes).

People also post here asking about high-zinc oils for flat-tappet engines a lot. Next time they post, tell them that zinc isn't what they really need but an oil with a thick base oil, such as a 15W-40 or a 20W-50. Or at least a 10W-30. Of course, moly and other AW/EP/FM additives are also crucial.

I will probably start following my manual and use 10W-30 in the next OCI. Perhaps, I'll put in the new Pennzoil Platinum SN Plus 10W-30, which will become available next month.

 

[Shannow]

Originally Posted By: Gokhan
I will probably start following my manual and use 10W-30 in the next OCI. Perhaps, I'll put in the new Pennzoil Platinum SN Plus 10W-30, which will become available next month.


An ILSAC 10W30...go for it...do the Harman Index thing to confirm.

Have a play with this concept...

https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4717883/Re:_Which_two_oils_would_you_m#Post4717883

 

[littleant]

Originally Posted By: Gokhan
Originally Posted By: littleant
Gokhan thanks for your post. Good read. A question if I can. My interest is with timing chains (3 in a 2010 mountaineer 4.0). Is it more important to get oil to the chains at startup (5w30) or when running (10w30) Summer/Winter. Ford specs 5w30 and the one engine that never changed to 5w20. I use QSUD 5w30. At these weights does it even matter?

You live in Vermont. I'm guessing it gets pretty cold there in the winters. My manual says don't use 10W-30 below -10 F (-23 C). Of course, you may have a partially heated garage. You may not get much oil anywhere when it gets colder than that.

I don't know how cold you can go before startup wear due to viscosity becomes an issue. Some Canadians use 10W-30 and you can ask if any of them have an oil-pressure gauge and what they think about it.
Thank you Sir The mountaineer stays garaged and is not driven all winter prevents rust. Vehicle used is a 02 jeep. Our lowest temperature this winter was a week of -35 to -40 below. Snowing as I write this

 

[wemay]

Originally Posted By: Gokhan
I should say that this knowledge of the importance of base-oil viscosity vs. VII-improved viscosity is brand-new to me! I'm very glad that Shannow pointed out to the Nissan paper and I ran into it. Of course, it's only one paper, but it makes you think again about oil viscosity!

Long time ago I always wondered why my manual would recommend 10W-30 but not 5W-30, except in extremely cold weather. I just couldn't find an answer anywhere. Later I learned about oil shear (viscosity loss) and 5W-30 having more permanent oil shear than 10W-30 because it had more VII. So, this seemed to be the answer. However, now that I learned about the importance of the base-oil viscosity, I think that the real answer wasn't oil shear, but base-oil viscosity!

Now, you can say that it's an outdated 1985 manual. However, this is from the 2018 Kia Stinger manual:

For their TGDI engine, they recommend 5W-30, 10W-30, and 5W-40, but no 0W-40! Most people who read that thread thought it could be an oversight by Kia, but now, I think that it's because of the base-oil viscosity and the fact that these TGDI engines have timing-chain wear problems.

Timing chain isn't the only place where base-oil viscosity could be important. The valvetrain and parts of rings and cylinder linings also operate in similar lubrication regimes (boundary and mixed lubrication regimes).

People also post here asking about high-zinc oils for flat-tappet engines a lot. Next time they post, tell them that zinc isn't what they really need but an oil with a thick base oil, such as a 15W-40 or a 20W-50. Or at least a 10W-30. Of course, moly and other AW/EP/FM additives are also crucial.

I will probably start following my manual and use 10W-30 in the next OCI. Perhaps, I'll put in the new Pennzoil Platinum SN Plus 10W-30, which will become available next month.


Thanks for the thought... interesting.

 

[Garak]

I would be very skeptical about drawing any lessons in tribology from an owner's manual viscosity recommendation.

 

[slacktide_bitog]

Originally Posted By: Gokhan
They don't sell xW-40 PCMO in USA, except the M1 and its German cousin Castrol.

So, they are stuck with 0W-40 if they want a 40-grade oil in USA. I'm sure if 5W-40 PCMO was available here, Corvette would recommend that instead. I know there is Pennzoil 5W-40 but it's sort of a unicorn oil.


There is plenty of PCMO 5w40 in the US

PP 5w40
Valvoline's MST 5w40
Even WPP has a 5w40 (including Mag1's clear bottles)
AAP's CQ house brand has a 5w40 offering (it's made by Amalie/Wolf's Head)
Havoline 5w40
Liqui-Moly has a couple 5w40 offerings (and it's available at any Napa)

 

[PeterPolyol]

Originally Posted By: OVERKILL

Your first statement is correct, it isn't that simple. Did you look at the MRV values in the XOM blending table? Have you seen a 0w-40 with an MRV that low?

Yes PAO usage changes everything, but the principle remains the same. I think it's safe to say that blenders are choosing their base oil profile to meet the W rating they're blending for, and relying on VIIs to fluff kinematic viscosity up to the desired grade.

VHVI GrIII (FT/GTL), IV and V-based blends are no different, only they can get away with heavier base oil profiles (and higher HTHSV) because the cold-performance doesn't suffer as badly, so less VII and PPD are needed. Do you see the pattern? The M1 0W40 is robust because of it's heavier, yet synthetic, base oil viscosity. Choosing a heavier base blend allows a more robust finished product (the theme of the OP), M1 0W40 is no different, they follow the same rules, just with better cold flowing base blend.

OTOH the same benefits apply to even GrIII, IV, V bases- they'll perform even better if one removed or raised the W rating requirement and were left non-VMed. M1 0W40's same base blend without VMs would probably be one heck of a robust SAE20. A SAE 30 or 40 grade GrIII, IV, V, non-VMed base blend oil would probably allow the most notoriously stretchy timing chain live as long as the engine... hypotheticals I'd put my money on.



Originally Posted By: ZeeOSix

Except in the situations where the oil is so thick at cold start-up that the positive displacement oil pump goes into pressure relief. In a drastic example, if the oil was so thick that it cause the oil pump to hit pressure relief, and most of the oil volume was being shunted back to the sump or pump inlet, then that wouldn't leave much oil volume going to the engine's oiling system. In a situation like that, the engine is essentially getting starved of oil flow.

Even when the viscosity is TOTALLY INAPPROPRIATE for the extremely cold cranking temperatures, as in a late 80s? 10W30 GrI "candle in a jug" shown in the classic Esso video, that pump still forces it through the oil system right to the end of the line- eventually. Notice how that car didn't even start for a few minutes because of the viscous drag on the crank was so extreme from inappropriate viscosity- and the 80's Chrysler oil pump still transports the oil!
Another phenomenon related to dramatically inappropriate oil selections is when the oil pickup tube sucks a crater around itself in the oil pan, and the surrounding oil is too thick to refill the crater, and the pump starts sucking air. The pump was putting that goop somewhere else other than back at the inlet or into the pan. I mean, these are very sensational and extreme examples and hardly represent the 5W20 vs 0W20, or 5W30 vs 10W30 quibbled related to any modern engine oil in any non-extreme climate. There's not a chance I'd choose to run 0W20 in FL or TX- WHY? To what objective benefit? Remember, the original contention was that any lower W will outflow any higher W at all and any temperature above it's W rating thus providing superior start up wear protection, and that's bollocks.

 

[Shannow]

Originally Posted By: PeterPolyol
Remember, the original contention was that any lower W will outflow any higher W at all and any temperature above it's W rating thus providing superior start up wear protection, and that's bollocks.


Been battling that premise for over a decade...

 

[wemay]

Duplicate

 

[wemay]

Originally Posted By: slacktide_bitog
Originally Posted By: Gokhan
They don't sell xW-40 PCMO in USA, except the M1 and its German cousin Castrol.

So, they are stuck with 0W-40 if they want a 40-grade oil in USA. I'm sure if 5W-40 PCMO was available here, Corvette would recommend that instead. I know there is Pennzoil 5W-40 but it's sort of a unicorn oil.


There is plenty of PCMO 5w40 in the US

PP 5w40
Valvoline's MST 5w40
Even WPP has a 5w40 (including Mag1's clear bottles)
AAP's CQ house brand has a 5w40 offering (it's made by Amalie/Wolf's Head)
Havoline 5w40
Liqui-Moly has a couple 5w40 offerings (and it's available at any Napa)




...and STP 5W40

 

[ZeeOSix]

Originally Posted By: PeterPolyol
Originally Posted By: ZeeOSix
Except in the situations where the oil is so thick at cold start-up that the positive displacement oil pump goes into pressure relief. In a drastic example, if the oil was so thick that it cause the oil pump to hit pressure relief, and most of the oil volume was being shunted back to the sump or pump inlet, then that wouldn't leave much oil volume going to the engine's oiling system. In a situation like that, the engine is essentially getting starved of oil flow.

Even when the viscosity is TOTALLY INAPPROPRIATE for the extremely cold cranking temperatures, as in a late 80s? 10W30 GrI "candle in a jug" shown in the classic Esso video, that pump still forces it through the oil system right to the end of the line- eventually. Notice how that car didn't even start for a few minutes because of the viscous drag on the crank was so extreme from inappropriate viscosity- and the 80's Chrysler oil pump still transports the oil!


Eventually is correct. My point was that using the wrong oil in very cold climates certainly can cause oiling issues because a positive displacement oil pump still has a pressure regulator valve, and any time that valve is open it means some oil is not getting to the engine's oiling system. The Esso video certainly makes it pretty clear that running the wrong oil (even a 10W-30) in the Great White North in the dead of winter could be a very bad decision.

Originally Posted By: PeterPolyol
Another phenomenon related to dramatically inappropriate oil selections is when the oil pickup tube sucks a crater around itself in the oil pan, and the surrounding oil is too thick to refill the crater, and the pump starts sucking air. The pump was putting that goop somewhere else other than back at the inlet or into the pan.


The Esso video also covered some of that ... maybe it was in Esso Part 2. If the oil is so cold and thick that it causes the pump to suck air then that situation will definitely starve the engine of oil flow even more than if the pump's bypass valve was all the way open. And in that situation, if some "goop" does get to the pump, the pump will certainly be hitting pressure relief too. The bottom line is if you can't pump it well in cold weather then the flow to the engine suffers, and that the premise that a positive displacement oil pump will always ensure good oil flow is false under certain conditions.

 

[Gokhan]

Originally Posted By: Shannow
Originally Posted By: Gokhan
I will probably start following my manual and use 10W-30 in the next OCI. Perhaps, I'll put in the new Pennzoil Platinum SN Plus 10W-30, which will become available next month.

An ILSAC 10W30...go for it...do the Harman Index thing to confirm.

Have a play with this concept...

https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/4717883/Re:_Which_two_oils_would_you_m#Post4717883

I've calculated the A_Harman index for PP 10W-30:

Assuming HTHSV = 3.00 cP, A_Harman index = 0.929
Assuming HTHSV = 3.10 cP, A_Harman index = 0.960
Assuming HTHSV = 3.15 cP, A_Harman index = 0.975

So, chances are that the A_Harman index for PP 10W-30 is at least 0.960 or above. It's practically a SAE 30 monograde with a naturally high viscosity index, low CCS, and low MRV. It would be great for protecting the timing chain, valvetrain, piston rings, etc. if you believe the claims in the Nissan paper in the original post. NOACK is also assumed to be exceptional (reported by Shell to be 4.7% in the past).

How to calculate the A_Harman index

 

[OVERKILL]

Originally Posted By: PeterPolyol

Yes PAO usage changes everything, but the principle remains the same. I think it's safe to say that blenders are choosing their base oil profile to meet the W rating they're blending for, and relying on VIIs to fluff kinematic viscosity up to the desired grade.


That's basically the point I was making with respect to blender financials; price point. Two excellent examples are the Castrol Euro sisters, 0w-40 and 5w-40, one blended with PAO, the other not.

Then, we start looking at "expensive" 0w-20's like M1 EP versus "cheap" ones that are Group III, and then extending that comparison into the 5w-20 range. There's a lot of variance due to how the different blenders base their products.


Also, we can't forget OEM certifications/approvals here, which test for a lot of things including timing chain wear. Nissan spec'd 0w-40 for the GT-R and I'm sure there was a reason.

If we look at the MB 2012 spec for 229.1/229.3/229.31/229.5/229.51:
http://www.lubritecinc.com/PDF/MB_Spec_EO_Service_Oils_2012.1.pdf

Originally Posted By: Mercedes

M 271 Wear Test (MB DL, Wear, 250 h) c.)
Cam wear inlet / outlet valve (avg. max. wear 8 cams)
Piston ring wear radial @ ring 1 / ring 2 (avg.) e.)
Piston ring wear axial @ ring 1 / groove 1 (avg.) e.)
Ring sticking yes/no
Main Bearing wear (avg.) e.) / (max.)
Conrod Bearing wear (avg.) e.) / (max.)
Timing chain wear (elongation) %
Timing chain wear (single chain link) %
Bore polishing (xmm) - max. value of 6 cylinders %


and then:
Originally Posted By: Mercedes

OM 646 DE22LA Wear (CEC L-99-08) c.)
Cam wear inlet (avg. max. wear 8 cams)
Cam wear outlet (avg. max. wear 8 cams)
Cylinder wear (avg. 4 cylinder)
Bore polishing (13 mm) - max. value of 4 cyl.%
Piston cleanliness (avg. 4 pistons) merit
Engine sludge avg.merit
Ring sticking yes/no
Tappet wear inlet (avg. max. wear 8 cams)
Tappet wear outlet (avg. max. wear 8 cams)
Bearing wear main / con rod bearing e.)
Piston ring wear axial @ ring 1 e.)
Piston ring wear axial @ ring 2 e.)
Piston ring wear axial @ ring 3 e.)
Piston ring wear radial @ ring 1 e.)
Piston ring wear radial @ ring 2 e.)
Piston ring wear radial @ ring 3 e.)
Timing chain wear (elongation)%
Oil consumptiong/test
Soot
Viscosity increase at 100°C


So, do we trust posit of base oil viscosity for wear control in the timing chain area, or do we look at spec's with actual engine tests that physically measure it? I know which way I'm leaning... (and this is why I've always been a proponent of the Euro lubes and approvals).

 

[PeterPolyol]

*cough*MB M272/273*cough*
I bet MB is paying extra attention to timing chain wear, now. Actually, the whole entire industry is! VAG, BMW have been on their PAO LL specs for some time. Can't cite either as being exemplary

 

[Shannow]

Originally Posted By: OVERKILL
So, do we trust posit of base oil viscosity for wear control in the timing chain area, or do we look at spec's with actual engine tests that physically measure it? I know which way I'm leaning... (and this is why I've always been a proponent of the Euro lubes and approvals).


All of the timing chain stuff that I've read about for years treats timing chains as a three body wear proposition, not purely metal to metal (as I think the Nissan does)...and primarily diesels, but bear with me.

Three body wear is the two wear surfaces and something in between them (soot particle, dirt, whatever)...they use simulated soot (carbon black) to control the size and amount of the contamination.

No hydrodynamics in the link pin, but as the load is applied, there's a "squeeze" film effect as the oil is squeezed from the clearance...more viscosity, the longer it takes to squeeze out, the thicker the remnant (diminishing) film.

If this is bigger than the general particle size, low wear.

If it's not, wear goes up.

If the FMs help lubricate the third body, less wear. and yes, after the particles are smashed, metal to metal less wear.

 

[ZeeOSix]

Originally Posted By: Shannow
All of the timing chain stuff that I've read about for years treats timing chains as a three body wear proposition, not purely metal to metal (as I think the Nissan does)...and primarily diesels, but bear with me.

Three body wear is the two wear surfaces and something in between them (soot particle, dirt, whatever)...they use simulated soot (carbon black) to control the size and amount of the contamination.

No hydrodynamics in the link pin, but as the load is applied, there's a "squeeze" film effect as the oil is squeezed from the clearance...more viscosity, the longer it takes to squeeze out, the thicker the remnant (diminishing) film.

If this is bigger than the general particle size, low wear.

If it's not, wear goes up.

If the FMs help lubricate the third body, less wear. and yes, after the particles are smashed, metal to metal less wear.


Might also be a good reason to use a high efficiency oil filter to keep as much debris out of the oil as possible.