Kirkland 5W-20 vs 0W-20

I still don't subscribe to the idea that a 0W-20 is always superior to a 5W-20. The only time I think that's applicable is when cranking in freezing temperatures.

Let's take a couple 20 grades with the same KV100.

View attachment 115183

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I have a very hard time believing that flow is going to differ much anywhere above 0°C with these two oils. I think any difference would be trivial to even mention. The traction differences in the bearings between quality of base oils would likely have a greater impact on oil flow.


I mean, your own graph shows my point, up to ~60c.. There is substantial differences in viscosity between 0c and 60c. Everyone in the US basically, lives below 140f ambient temperature. With below 0C being regular for the majority of US and Canada, and still occasionally in most of the US, except for very southern states. Which, again with the same HTHS, even in the most southern states, there is at worse case scenario - no differences between 5w20 and 0w20. At best case, you're going to be getting a better product.

And you can see my previous study on piston ring wear.

But this entire conversation is absolutely trivial to begin with. The fact this has gone on this long, is absurd.
 
OK, think we are mostly on the same page with regards to the caveats. The PD pump will, assuming we aren't on the relief, get oil to anywhere pressure lubed at roughly the same time, I think @Shannow posted a study from the SAE that showed full envelopment time between different oils at different temperatures. However, the places I mentioned, like the pistons and cylinder walls that are splash/spray lubricated, will receive lubrication sooner/receive better lubrication with an oil with a better Winter rating.

This won't change the time it takes for the AW additives to activate, so wear is elevated until they are, hence the claims about start-up (warm-up) wear.

Would depend on the relief pressure set on the pump and whether we are hitting it, so there are some variables we need to account for here. I believe you and Zee covered that in your discussion already however.

Yes, I'd agree with that. It isn't about oil pump or system volume at these locations but how effectively oil can be sprayed/cast on them, where a better Winter rating can provide better lubrication faster.

Yes, pre-lubers ensure that there's oil in locations it needs to be to reduce reliance on existing AW coating build-up, potential removal of, and subsequent wear, while lubricant AW chemistry is not yet active. Wear is still elevated, but it is reduced. This can be improved further by ensuring that the lubricant is also pre-heated, which we also see in some applications.

Yes it is, lol, but I sense that it needed to be mentioned given the direction this conversation has gone, lol.

Don't worry about the quotes, I had no problem reading what was written.

Since we are calling out caveats and have covered the start-up/warm-up wear ones, we should also consider what using lighter base oils means at the other end of the spectrum. Assuming the same family of base oils being used for both products, the 0W-20 is going to have a lighter base oil blend, which means a higher Noack, higher VII content and higher likelihood of experiencing mechanical shear. Depending on the application, this may also increase the likelihood of ring land area deposits (thinking of the Thin Film Oxidation Test and Sequence IIIG or its successors for example). Of course some manufacturers change-up the base oil blend when going with the a 0W-xx. Mobil has a history of using PAO, in varying quantities, when producing these for example.

I apologize in advance for taking this subject even more into the nuance, but member @Gokhan has produced a calculator where he calculates base oil viscosity and "full shear" viscosity as well as VII concentration:


It's an interesting exercise, though one has to keep in mind that these are estimates.

Great discussion so far! Appreciate the engagement.


Vavoline synthetics will be the closest to the Kirkland for comparison. They (at least last I checked) used Adnoc group III's and Afton additives. This may have changed since the last time I've investigated this at all, which was over a year ago when the ****storm with additives started. Now, Vavoline and Warren may use different quality of additives, which is also debatable.

This is all getting into the very niche nuances. We're talking about a 5000 mile OCI, in a normal application, assuming no extreme temps or conditions. Both products would be absolutely fine. But, assuming same cost - which, on the wholesale level, there is 0 price difference between a FS 5w20 and 0w20 - non-dexos. Almost no one approves Dexos 5w20's anymore because the market isn't there. I digress. Assuming same price difference, same OCI, same engine conditions: 0w20 will be the superior product in my opinion.

If we really wanted to get into the true nuances, we could talk about emulsification of the oil, beta ratios of filters, particulate wear. But the fact is, engines are designed to handle those, at least for the B10 of their life. Engines aren't using kingsbury bearings and expected to run tens of thousands of hours without shut down and service. Out of a modern gas engine, if we get 10,000 hours - I mean, wow. Even a modern diesel engine, if we get 20,000 hours before a rebuild - that's great.

In my history, the majority of failures I've seen in modern engines (both gas and diesel) is thermal cracks. Which means an event has happened that the engine got too hot anyways. And we'll also see cylinder scoring, gaskets fail, etc. This is normally caused by a non-lubricant related issue. That being said, I've also seen the occasional false brinelling of bearings - more so wheel bearings - but sometimes engine bearings, on cars that are transported a lot and run little. Race cars and such.

But again, this is real real into the weeds.
 
Maybe for some but not all. Is it beneath you?

Nope, it's keeping me from actually working. Which is fantastic. Being an oil nerd on the internet > Spread sheets, oil samples, oil prices and fleet issues.

Edit:

Imagine me laughing when I say this is absurd, in a fun way. It's great conversation, makes me re-read some articles that haven't been a while. Even broke out my STLE study book and went over my note!
 
Oh I thought you were retired. Sorry.


I'm 37 hah. I'm far from retired. Just been in the lubricants industry my entire life.


Now, would anyone like to discuss ISO 220 EP Gear oil and how it turned into a shaving cream consistency? As that has been my mystery I've been working on for a while. Still no answers. But this isn't the right thread for that.
 
Vavoline synthetics will be the closest to the Kirkland for comparison. They (at least last I checked) used Adnoc group III's and Afton additives. This may have changed since the last time I've investigated this at all, which was over a year ago when the ****storm with additives started. Now, Vavoline and Warren may use different quality of additives, which is also debatable.

This is all getting into the very niche nuances. We're talking about a 5000 mile OCI, in a normal application, assuming no extreme temps or conditions. Both products would be absolutely fine. But, assuming same cost - which, on the wholesale level, there is 0 price difference between a FS 5w20 and 0w20 - non-dexos. Almost no one approves Dexos 5w20's anymore because the market isn't there. I digress. Assuming same price difference, same OCI, same engine conditions: 0w20 will be the superior product in my opinion.

If we really wanted to get into the true nuances, we could talk about emulsification of the oil, beta ratios of filters, particulate wear. But the fact is, engines are designed to handle those, at least for the B10 of their life. Engines aren't using kingsbury bearings and expected to run tens of thousands of hours without shut down and service. Out of a modern gas engine, if we get 10,000 hours - I mean, wow. Even a modern diesel engine, if we get 20,000 hours before a rebuild - that's great.

In my history, the majority of failures I've seen in modern engines (both gas and diesel) is thermal cracks. Which means an event has happened that the engine got too hot anyways. And we'll also see cylinder scoring, gaskets fail, etc. This is normally caused by a non-lubricant related issue. That being said, I've also seen the occasional false brinelling of bearings - more so wheel bearings - but sometimes engine bearings, on cars that are transported a lot and run little. Race cars and such.

But again, this is real real into the weeds.
But, ultimately, that's some of the best conversation we have on here, ones like this where we are so far into the nuance that we are discussing things that, for all intents and purposes, don't really matter, but from a technical perspective, is tangible, and the quality of that conversation and knowledge exchanged has value :)

Circling back to the last paragraph of my post you quoted, what are your thoughts on the base oil viscosity and its impacts at the other end of the spectrum? I mentioned some examples that I thought relevant.
 
I mean, your own graph shows my point, up to ~60c.. There is substantial differences in viscosity between 0c and 60c. Everyone in the US basically, lives below 140f ambient temperature. With below 0C being regular for the majority of US and Canada, and still occasionally in most of the US, except for very southern states. Which, again with the same HTHS, even in the most southern states, there is at worse case scenario - no differences between 5w20 and 0w20. At best case, you're going to be getting a better product.

And you can see my previous study on piston ring wear.

But this entire conversation is absolutely trivial to begin with. The fact this has gone on this long, is absurd.
I own two GM’s, one Jeep, and one Lexus FF’d with 0W20 - and bought in Houston …
… these type of debates go forever here - and another one will hatch next week …
 
But, ultimately, that's some of the best conversation we have on here, ones like this where we are so far into the nuance that we are discussing things that, for all intents and purposes, don't really matter, but from a technical perspective, is tangible, and the quality of that conversation and knowledge exchanged has value :)

Circling back to the last paragraph of my post you quoted, what are your thoughts on the base oil viscosity and its impacts at the other end of the spectrum? I mentioned some examples that I thought relevant.


I believe we need to cover a few things about base oils. Part of this is the obvious NOACK volatility.

So we'll take adnoc as I have the specs in front of me currently:
ADBase 4cSt - 132 VI / 13.7 Noack
ADBase 6cSt - 139 VI / 7.5 noack
Adbase 8cSt - 136 vi / 2.3 noack

Naturally with pure Group III's, to his the 0wXX you're going to need to run a higher noack, which could contribute to more wear.

Mobil SpectraSyn 3.5 comes in right around 12 Noack. So clearly, as we get into the 0w16's, 0w12's and eventually the 0w8's - We're going to see more PAO usage again.

Here is a good Article: https://www.stle.org/files/TLTArchi...bsiteKey=a70334df-8659-42fd-a3bd-be406b5b83e5

I do think we'll see blends with Group III's to keep the price down, as development furthers into the ultra-light weights. We may see hypothetically a 5w16 or a 5w12 even, and this would really help combat the NOACK issue, as we've discussed. But what's going to be key, is how does the industry handle the Noack problem and I don't think there is a solid answer there.

Part of it, is going to group III+ base oils, or just better base stock production technology for group III's. We've seen group 3's go from an average of 120-125 Vi to over 140 just with traditional group III's. Shell's group III's are even higher and have less NOACK than traditional ones. So what will be the next advancement in GTL be? Or are we topped out in Group III technology?

PAO's - are we going to see a further investment in production of PAO's? Are refiners willing to put that money out? Or will we see a trend to push consumer education? Lower OCI intervals to fix the Noack problem and the price point problem?


Beyond that, let's take into other considerations. We know Group IV base oils have the worse foaming characteristics. We can easily defeat foam, which isn't a major issue really, but what are the long term implications of that?

On top of this, we need to look at OEM engine technology changing - or is ICE dead?

My opinion, with the 0w20 vs 5w20 - I think over all, you're fine using group III's, even with slightly more noack. I don't think you're going to see a bunch of deposit changes between a 5w20 and 0w20, assuming well formulated oils.

Now, when you start talking 0w16 and below, I think PAO's will be the superior product, but I don't believe we have the tonnage to support the entire market going to PAO's. And as we push LVLV, we're going to see more usage of PAO's if the market allows it.


Sort of a non-answer, because I don't think there is a good answer right now besides 0w20 vs 5w20 as an example. I think if we see a 0w12 PAO vs a 5w12 PAO/III - that's going to be more interesting. However it's all hypothetical right now.
 
I think we've gone TOO FAR and deep into the weeds.
Let's recap his basic questions...
Oil-shopping for two Honda vehicles that specify 5W-20 oil (one K20 one K24), thinking Kirkland, and wondering if 0W-20 is a better choice....
Sidebar question, is it worth paying a few extra bucks for something like Valvoline for a stronger additive pack? Not for longer OCIs but for general wear protection. OCI will be 5k on both.

We're talking about:
- Honda engines (generally very sound and reliable)
- shorter OCIs (5k miles)
- thin oil versus ever-so-slightly thinner oil
- well constructed house brand and well constructed brand name products

NO WAY IN HADES WILL THERE BE ANY TANGIBLE, DISCERNIBLE DIFFERENCE in terms of wear control. I don't care which brand or grade of lube he chooses, the engine will never be able to tell them apart once they are run in the crankcase, when it comes to what matters; outputs are FAR more important that inputs.

I challenge any of you to PROVE that I'm wrong here. Don't put marketing hype up as "evidence". Show me real world raw data that exhibits a statistically significant result, then I'll listen. Short of that, this is an exercise in futility.
 
The presentation is just for fun, nothing directly applicable to the current discussion, besides maybe something like the crank shaft bearings.
Crank shaft journal bearings are not Elasto-Hydrodynamic ... they are just plain hydrodynamic. Something like a roller bearing or a valve rocker arm on the end of a valve stem would be applicable, like the components shown in the paper on page 6.
 
Crank shaft journal bearings are not Elasto-Hydrodynamic ... they are just plain hydrodynamic. Something like a roller bearing or a valve rocker arm on the end of a valve stem would be applicable, like the components shown in the paper on page 6.

Yeah I wasn’t thinking at 821am. I had just woken up 😂
 
But this entire conversation is absolutely trivial to begin with. The fact this has gone on this long, is absurd.
Yes, the difference between 0W-20 and 5W-20 is trivial unless you're doing really cold start-ups in the dead of winter. The W rating was invented for a reason. Not going to matter at all in warmer climates. "Absurd" ... yeah, welcome to discussions about oil and Tribology. 😄
 
Imagine me laughing when I say this is absurd, in a fun way. It's great conversation, makes me re-read some articles that haven't been a while. Even broke out my STLE study book and went over my note!
Yep ... a good debate always makes people who are interested in actually backing up their claims to go dig up the information, which helps everyone maybe learn something they didn't know, or was looking at it in an unclear way. Everyone benefits in the end IMO if the discussions stays mainly technical in nature.
 
Yes, the difference between 0W-20 and 5W-20 is trivial unless you're doing really cold start-ups in the dead of winter. The W rating was invented for a reason. Not going to matter at all in warmer climates. "Absurd" ... yeah, welcome to discussions about oil and Tribology. 😄

Now the question is: At what point do you go to a block heater? and ignore the CPP?

Personally, if I lived regularly at 0F, I would either park in a heated garage, or use a block heater. I know where Tribology tells us where is 'safe' and where isn't 'safe' for oil in cold weather. But you're also now putting in human costs: 1. Actually having a warm ~Ish car to get into. 2. Stopping the chance of premature wear. 3. Electrical costs. 4. Building costs, etc.


Even where I am, we get 0f enough that I park my F150 inside an insulated garage. It keeps it about 10F warmer than outside temps.
 
I would change "lower-volatility" with "higher-base-oil-quality". For example, an XOM SpectraSyn 4 PAO with a higher Noack should perform equally or better (probably better because it is thinner and thus has a lower aniline point (better solvency)) than an XOM SpectraSyn 6 PAO with a lower Noack., contradicting the authors' conclusions above.

Relating to the discussion of oil warmup, should we consider the specific heat of the base oil? Take an 8 cSt group III vs a 4 cSt PAO, which have a specific heat of ~1,980 J/Kg-K and ~2,150 J/Kg-K respectively at 40°C. SpectraSyn 4 is ~3.1 Kg/gal and Yubase 8 is ~3.2 Kg/gal.

Let's take 1 gallon of oil and heat it by 40°C to 80°C.

Q = MCΔT

Q = Energy input required
M = Mass of the oil
C = Specific heat
ΔT = Temperature delta

For the 4 cSt PAO, we need 266.6 KJ of energy to heat 1 gallon by 40°C.

Q = 3.1 kg x 2,150 J/Kg-K x 40 K
Q = 266,600 J
Q = 266.6 KJ

For the 8 cSt Group III, we need 253.4 KJ of energy to heat 1 gallon by 40°C.

Q = 3.2 kg x 1,980 J/Kg-K x 40 K
Q = 253,440 J
Q = 253.4 KJ

So the 4 cSt PAO requires 5.2% more heat input than the 8 cSt Group III to raise the temperature by 40°C. Now of course this isn't exact as the specific heat and density changes across that temperature range, but the difference between them should track linear.

While it's not a huge difference, the group III base oil should reach the optimum temperature for additive reactivity sooner than the PAO. Combine that with group III's better natural solvency and additive response.

The example above would be like comparing a 0W-20 that's majority PAO (+VII) to a 10W-20 that's straight 8 cSt GIII.

What I'm getting at is the water here is much muddier than it may seem at the surface.

EDIT: It's worth noting that PAO also displays a lower traction coefficient in MTM. With less hydrodynamic friction, less heat is generated, further slowing the warmup of the PAO based oil.
 
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I believe we need to cover a few things about base oils. Part of this is the obvious NOACK volatility.

So we'll take adnoc as I have the specs in front of me currently:
ADBase 4cSt - 132 VI / 13.7 Noack
ADBase 6cSt - 139 VI / 7.5 noack
Adbase 8cSt - 136 vi / 2.3 noack

Naturally with pure Group III's, to his the 0wXX you're going to need to run a higher noack, which could contribute to more wear.

Mobil SpectraSyn 3.5 comes in right around 12 Noack. So clearly, as we get into the 0w16's, 0w12's and eventually the 0w8's - We're going to see more PAO usage again.

Here is a good Article: https://www.stle.org/files/TLTArchi...bsiteKey=a70334df-8659-42fd-a3bd-be406b5b83e5

I do think we'll see blends with Group III's to keep the price down, as development furthers into the ultra-light weights. We may see hypothetically a 5w16 or a 5w12 even, and this would really help combat the NOACK issue, as we've discussed. But what's going to be key, is how does the industry handle the Noack problem and I don't think there is a solid answer there.

Part of it, is going to group III+ base oils, or just better base stock production technology for group III's. We've seen group 3's go from an average of 120-125 Vi to over 140 just with traditional group III's. Shell's group III's are even higher and have less NOACK than traditional ones. So what will be the next advancement in GTL be? Or are we topped out in Group III technology?

PAO's - are we going to see a further investment in production of PAO's? Are refiners willing to put that money out? Or will we see a trend to push consumer education? Lower OCI intervals to fix the Noack problem and the price point problem?


Beyond that, let's take into other considerations. We know Group IV base oils have the worse foaming characteristics. We can easily defeat foam, which isn't a major issue really, but what are the long term implications of that?

On top of this, we need to look at OEM engine technology changing - or is ICE dead?

My opinion, with the 0w20 vs 5w20 - I think over all, you're fine using group III's, even with slightly more noack. I don't think you're going to see a bunch of deposit changes between a 5w20 and 0w20, assuming well formulated oils.

Now, when you start talking 0w16 and below, I think PAO's will be the superior product, but I don't believe we have the tonnage to support the entire market going to PAO's. And as we push LVLV, we're going to see more usage of PAO's if the market allows it.


Sort of a non-answer, because I don't think there is a good answer right now besides 0w20 vs 5w20 as an example. I think if we see a 0w12 PAO vs a 5w12 PAO/III - that's going to be more interesting. However it's all hypothetical right now.
Basically echoing my thoughts with regards to the divide between Group III and PAO. Of course you can get away with using a heavier PAO because the CCS visc is a lot lower, which will reduce Noack further.

Shell's GTL 4 has a Noack of 12% and a VI of 135. Great CCS visc at -30C though, 1,000cP. Given the increase in use of GTL across Mobil's lineup, it's clear that these bases are cost competitive and can supplant or augment PAO use, reducing formulating costs.

To answer your question about further improved PAO's, well, Mobil has started developing their SpectraSyn MaX product line. The first entry is a 3.5cP product with an 11.6% Noack, much lower than PAO 3.6 (I assume a CP product) which has a Noack of 17%, or even their own SpectraSyn 4 with a Noack of 14%. So, I would guess that we will indeed see more product showing up in this new portfolio going forward.

We are obviously splitting already split hairs at this point, but I'm sure controlled testing would yield some minute improvements with these higher grade bases.
 
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