SAE Paper on Engine Wear with 20 wt. oil

[Yolo]

So I’ve got a 2015 pentastar with 104k and it’s had 5w20 it’s whole life - mostly Mobil 1 with some Castrol and Valvoline OCI’s. I’ll be sure to tear it down at 150k.

 

[wwillson]

So I’ve got a 2015 pentastar with 104k and it’s had 5w20 it’s whole life - mostly Mobil 1 with some Castrol and Valvoline OCI’s. I’ll be sure to tear it down at 150k.

Don't I have a Pentastar with 150k that still runs like new.

 

[Cujet]

Don't I have a Pentastar with 150k that still runs like new.

Ha! Child's play, one of our sister companies ran a small fleet of modular engine Ford delivery vans to 900K miles on M1. They'd scrap 'em when the engine failed, generally a head gasket leaking coolant externally, followed by overheating.

 

[PimTac]

i think one of these "studies" they "formulated" their own 0W-20 because none were generally available and the only 20W oils then existed as racing oils, which, they either couldn't afford, or were afraid they might thwart their experimenter confirmation bias....

That statement is funny. They didn’t want to run a racing oil because of bias so they made up their own? That would invalidate their findings.

 

[ka9mnx]

i think one of these "studies" they "formulated" their own 0W-20 because none were generally available and the only 20W oils then existed as racing oils, which, they either couldn't afford, or were afraid they might thwart their experimenter confirmation bias....

There were plenty of off the shelf x20 oil in 2010 but I think you are right about their own blend for, both, the x20 and x30 oils tested. But in no way did they bias one oil over the other.

 

[Jackson_Slugger]

There were plenty of off the shelf x20 oil in 2010 but I think you are right about their own blend for, both, the x20 and x30 oils tested. But in no way did they bias one oil over the other.

Who said the study was done in 2010? I'd be surprised if anyone posted any study newer than 2000. It was probably posted HERE in 2010....

 

[ka9mnx]

Who said the study was done in 2010? I'd be surprised if anyone posted any study newer than 2000. It was probably posted HERE in 2010....

No, in the original post he mention 2010 which is, I believe, the paper I have with (approx) that era.

I do have other papers on the subject that are much older than 2010, though.

 

[Jackson_Slugger]

No, in the original post he mention 2010 which is, I believe, the paper I have with (approx) that era.

I do have other papers on the subject that are much older than 2010, though.

The OP pretty clearly doesn't state anything definitely and can't seem to remember, but I took it that he read the thread around 2010. But even if it were from '10, why bother with well over a decade of cars using 5W-20 on the road and many with well over 200K on the clock?

 

[buster]

Before the switch to 20 wt oil there was a paper (pretty sure by SAE) that described shorter engine life of 20 wt as compared to 30 wt oil.

As I call the requirement was that the engine would last 200K miles. I recall that number got reduced to 150K miles. Wish I could resurect that information. It was around 2010.

I don't remember that one but I believe you.

There was also a study conducted by Ford and CP where the 5w20 outperformed their own 5w30. Shell also had a good paper on 20 grades. Early 2000's maybe.

 

[SubieRubyRoo]

Its assumed at 100C (engine operating temp). 20 wt. =8 cSt. 30 wt = 10cSt

Agree, Al, after your edit. Just pointing out that some engines go to much greater lengths to carefully control the oil temps, and not necessarily at 100C. That was all I meant.

 

[cheesepuffs2]

If you look at the manuals for new cars in places like Australia, they will show a range of oil weights that are compatible based on temperature with the same engine that here they will spec purely at 0W-16/20. So if the oil weight has to do with new bearing width or other design changes, how is this possible?

This is what has convinced me to step up to 5W-30 from 20 weights too. If 20 weights are equal for protection, then why do non-CAFE countries get owners manuals that call for thicker oil for the same temps where US owners manuals call for exclusively 20 weights?

 

[cheesepuffs2]

As always, UOA results do not provide engine wear information.

Exactly. Unless you are measuring your bearings before and after their service life, then UOA does not indicate total engine health. People lean on UOAs for way too much.

 

[Jetronic]

Agree, Al, after your edit. Just pointing out that some engines go to much greater lengths to carefully control the oil temps, and not necessarily at 100C. That was all I meant.

They tend to go higher now even. Oil temps are tied (with an elastic band, there's some stretch) to the coolant temps and coolant temps have gone up. Some cars go as far as actively controlling the thermostats to run even hotter.

 

[SC Maintenance]

They might not have 0W-16 in Coober Pedy.

Maybe. This is the chart for my Toyota 2.5 in Australia. Basically you can run anything you like.

Also, in the USA it says you may use 0W-20 if 0W-16 is not available, but you MUST change it back to 0W-16 in 5000 miles - at the next 6 month service interval - rather than the specified 10K interval - or your car will self destruct (well I added the last part, couldn't resist) They give no such warning in Australia.

There are enough thin vs thick arguments on this board that I don't think we need anther, but I think you can infer from this at least that the engine oil viscosity has to do with a lot more than simply lubrication.

I personally don't have an issue running 0w-16 in my engine, but do prefer 0W-20.

 

[cman]

Maybe. This is the chart for my Toyota 2.5 in Australia. Basically you can run anything you like.

Also, in the USA it says you may use 0W-20 if 0W-16 is not available, but you MUST change it back to 0W-16 in 5000 miles - at the next 6 month service interval - rather than the specified 10K interval - or your car will self destruct (well I added the last part, couldn't resist) They give no such warning in Australia.

There are enough thin vs thick arguments on this board that I don't think we need anther, but I think you can infer from this at least that the engine oil viscosity has to due with a lot more than simply lubrication.

I personally don't have an issue running 0w-16 in my engine, but do prefer 0W-20.

View attachment 129488

I have been researching owners manuals from other countries as well for my Toyota. I have a 2019 Corolla with the 2ZR-FE (I live in Oregon, USA). Mine specs 0W-20 oil only... but that is only the case in the US owners manual.

Well look what I found in the Australia owners manual.. it says to use 5W-30!! and I am pretty sure there are Dyno 5W-30s that meet the certifications it lists as well. And this is referenced for a 2019 Corolla with a 2ZR-FE engine.. the same exact year and engine as my car. And of course, my US Owners manual says only, 0W-20, it mentions that you can use 5W-20 in an emergency but immediately switch back to 0W-20.

This whole thing leaves a bad taste in my mouth. I understand Australia has a much more mild climate than many places in the US.. but that's why I believe the "temperature range chart" is so useful.


I am not saying you cannot get 200k+ with 0W-20 or 0W-16... but what I am wondering is can you instead get 300k or 400k by ditching the super thin oils?


Here is a snippet from the Corolla owners manual for Australia 2019 model which spec's 5W-30 for a *minimum*

 

[#18FAN]

Says it all

 

[spasm3]

Says it all
View attachment 129493View attachment 129494

I'd drive it carefully home taking care to keep the revs low, then dump the 0w-16 for some 0w-40.

 

[#18FAN]

I'd drive it carefully home taking care to keep the revs low, then dump the 0w-16 for some 0w-40.

What if it Lives in 115F Temps driving 90mph

 

[spasm3]

115F and 90 mph? Forget driving home. I'd change it it in the dealer parking lot for 0w-40!

 

[cheesepuffs2]

I don't see how anybody can deny that thicker is better based on these manuals. We see 20 weights being defended often as "well the manufacturer knows best", but that's really not the whole story, because the manufacturer recommends 30 weight when they don't have their hands tied to maximize fuel economy tests for every last percentage point.

To me, that says the manufacturer doesn't recommend 20 weight, but the hoops they have to jump through do. Without CAFE tests, it seems we'd be steered into running 30 weights like elsewhere in the world, and like thinner oils are a calculated decision to reduce engine wear by "enough" but not as well as possible.