Yes kschachn you are right about the shear, but I think MadMaxx may have been referring to oxidative thickening of the oil and used the wrong term by mistake
CAFE Standards in the US and Oil Grades
- Thread starter johdirt784
- Start date
My country doesn’t tell manufacturers how to make oil or how to make cars, or what oil to put in your car. They just tax the bejesus out of fuel, and let market forces do the rest.
So economical 4 cylinder cars are very popular but we tend to run thicker oils in them. That’s because a 4-cylinder Corolla on 15W40 still uses a lot less fuel than a V8 truck on 0W20. The vehicle is the significant variable here. Having said that, 5W30 is becoming a very common grade which makes sense.
Gokhan famously put 15W40 in his ~ 2003 Corolla. This was after using legendary TGMO 0W20 It did not stop oil consumption, even after valve stem seal replacement. It had to be piston ring coking.
The "performance" became sluggish. Of course this was in Southern California, not the streets of Sydney or The Outback.
It would definitely work on either.
Here is a link to the 2018 Toyota Camry Hybrid VVTI manual printed for Australia, to keep your factory warranty you can only use 0W16 or 0W20 or 5W20 or 5W30 or 10W30 or 15W40.
OVERKILL
$100 Site Donor 2021
That's quite the leap, inferring that from acknowledging that the standards imposed on these ultra-thin oils are to ensure adequate performance under increased boundary and mixed regime conditions, that this somehow implies discounting the efficacy of those protocols setup by these agencies.
Honda's answer was to go with wider bearings, as I already noted. "film strength" gets tossed around a lot (look at the RAT testing) but the issue with bearings is lower MOFT offered by thinner lubricants (and lower HTHS) so the bearing configuration/design has to be altered to avoid hydrodynamic turning into mixed or boundary, which bearings aren't supposed to operate in. How that's achieved I'm sure includes a number of methods, but one of the easiest is as Honda has done, make the bearings wider.
This is compounded by the fact that ultra-light bases used in these oils are far more likely to flash-off (hence the increase in Noack and exception made to accommodate that) which would be the reason for mitigation mechanisms, like coatings, changes in ring pack design...etc to deal with this. Toyota of course really buggered this up at one point, as has GM (Saturn).
And that's the case for any modern engine, whether it specs 0w-8 or 0w-40. BMW was doing this stuff when they were still spec'ing LL-01 with an HTHS >=3.5cP, same with Mercedes.
Yes, so I'm not sure where the disconnect is here?
Working to mitigate the caveats inherent with ultra thin oils so that performance is acceptable does not translate into better protection, which was your claim. If the oil provided better protection, these mechanisms wouldn't be required.
It's about adequate performance while returning better fuel economy. Which translates to an acceptable engine lifespan where the wear profile has been validated, through extensive testing, to avoid things like obscene oil consumption and aligning with the projected useful life of the vehicle it is fitted to.
OVERKILL, there is no way I am going to pretend I have the chops that you and many others have.
I am merely a consumer who happens to have almost 4 million miles of experience, and much of that with very thin motor oil.
In a thread I will start in about a week, I will maybe go into detail, and as promised, it will be titillating.
Meanwhile, I am merely perceiving what SAE/ILSAC themselves state.
Application and driving conditions are always the key factor.
I remind everyone that the Porsche C20 oil specification does exist.
I am merely a consumer who happens to have almost 4 million miles of experience, and much of that with very thin motor oil.
In a thread I will start in about a week, I will maybe go into detail, and as promised, it will be titillating.
Meanwhile, I am merely perceiving what SAE/ILSAC themselves state.
Application and driving conditions are always the key factor.
I remind everyone that the Porsche C20 oil specification does exist.
4WD
$50 site donor 2024
something to add in these debates is when making tolerance and bearing clearance “has always been tight” comments - there is more to it. engine builders now have more technology to hold tolerance in the Tri axis realm - lots of analytical and predictive models - easier FEA and FMECA … QA/QC equipment is just amazing now … metallurgy has advanced with technology. Builders can/do react - sometimes getting it wrong but the challenge is to bring more HP and MPG together - And yes, they have to deal with the “best in class” mindset …
I‘d be more worried about a turbo twisted I4 making the power of my 5.3L … that big/stiff stiff short block is fine with 0W20 considering the many changes in this generation … (and had already migrated to 6 bolt mains)
If I see 5W30 on sale … would put that in there too. But the drama here over that kind of choice is annoying …
Worry more about the rest of your powertrain …
I‘d be more worried about a turbo twisted I4 making the power of my 5.3L … that big/stiff stiff short block is fine with 0W20 considering the many changes in this generation … (and had already migrated to 6 bolt mains)
If I see 5W30 on sale … would put that in there too. But the drama here over that kind of choice is annoying …
Worry more about the rest of your powertrain …
Improvements are required re oxidation, deposits, valve train wear, sludge, varnish, corrosion. GF-6A oil is backwards compatible. This is independent of viscosity. API still respects the Laws of Physics.
What am I missing ?
What am I missing ?
Jackson_Slugger
$50 Site Donor 2022
There are cases where thicker oils actually increase burning, especially on some Toyota 1.8L's of this vintage...
You're right, these topics get discussed ad nauseam, then the questions change slightly only to reappear and get beaten to death again. FTR the thinies do their fair share of trolling too. Just saying.......
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