Who predicted that?... Al?
CAFE and the USE of Lower Viscosity Motor Oils
- Thread starter AEHaas
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Actually CAFE does in fact take into consideration fractional numbers ie. .001 in the MPG tests. We should all care at least a little bit. Human respiratory and asthma issues have been on the rise the past several decades and lower viscosity oils is one small effort that helps lower the carbon footprint of said automobiles that use lower viscosity oils.
I don't care. Pass the SAE 40, I'm getting mine until the whole mess goes up in flames.
"CAFE credits" are more complicated than just the ultimate MPG. But obviously manufacturers are trying to get as much measured MPG as possible, and using thinner motor oil is one of those methods.
No offense, but it's not relevant when it comes to CAFE standards. The fractional gain with one single vehicle doesn't matter to the vehicle owner but to the automaker, they take that fractional gain and multiply it by every vehicle they build. CAFE isn't even targeting consumers, it only affects the vehicle manufacturer.
And are engines failing due to using XX-20 weight oil ? Nope, not happening... The fact that some automakers are spec'ing XX-16 weight oil proves this.
BITOG = CAFE Obsessed.
If a manufacturer doesn't meet the required CAFE standards for any given model year, they are charged a penalty. Here's what Fiat Chrysler was penalized in 2016 and 2017. Must have been all those Hellcats, etc. 
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BITOG = CAFE Obsessed for a reason.
Maybe someone can explain this to me with some data or charts to back it up. If thinner oils truly protect an engine better, as some people here are alluding to, why is it some owners manuals will have text stating for sustained highway driving, or towing to use 5W30 instead of 5W20. This verbiage is in some owners manuals with cars that have 5W20 stamped on the fill cap. It has been mentioned here over the years many times. I seriously doubt 5W20 is going to protect an engine better under ideal operating conditions than a 5W30 would. It might offer a fractional gain in mpg, maybe. I'm not even thinking about cars that are tracked and call for a "thicker" oil for track use.
That's some big money. IIRC reading somewhere that Tesla made some nice money selling CAFE credits.If a manufacturer doesn't meet the required CAFE standards for any given model year, they are charged a penalty. Here's what Fiat Chrysler penalized in 2016 and 2017. Must have been all those Hellcats, etc.
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I don't care at all about my "carbon footprint" and will not take any action to reduce it. (Also I will not buy a newer vehicle that takes extreme measures to eke out a little more efficiency.)
Whining and moaning about it 24/7 every day year after year after year hasn’t accomplished a thing. Has anyone ever tried to actually do something about it besides complaining nonstop on the internet about it?BITOG = CAFE Obsessed for a reason.
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Ya, using a thicker oil.
That’s doing nothing to change the CAFE regulations so that’s a “no” other than complain about it.Ya, using a thicker oil.
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If a manufacturer doesn't meet the required CAFE standards for any given model year, they are charged a penalty. Here's what Fiat Chrysler penalized in 2016 and 2017. Must have been all those Hellcats, etc.
View attachment 53222
With my 6.4L averaging less than 11Mpg during the winter with in-town driving I'm expecting that isn't far from the truth, lol.
Who's whining and moaning about it? The discussions are pretty much always about why thinner and thinner oils are being specified and used, and that it's because using thinner oil can result in a hair more MPG which is what CAFE credits are all about - so therefore it's pretty easy to see that CAFE does indeed drive the use of ever thinner oil. And that ties into how using a thinner oil can result in less HTHS and less MOFT that can result in more engine wear depending on the use conditions of the vehicle.
It doesn't protect better, but if might protect "adequately". The very backbone of tribology shows that more viscosity results in more MOFT, which is the only thing that keeps moving parts from physically contacting each other. The first line of defense to prevent wear is the film thickness (MOFT) which is dependent on viscosity, then when that fails and MOFT goes to zero, the second line of defense is film strength (AF/AW additives). Why operate closer to the zero MOFT realm when you have the choice not to by using a bit higher viscosity.
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Way I see it I get better mpg overinflating my tires to 45 psi. I run 10w-30 in the winter 5w-40 in the summer. They don't make a ton of PCMO 10w-40s. I'd rather my car last longer. Think of the greenhouse emissions that go into manufacturing a car.
It ain’t like old times Billy.
Like I said, those “discussions” have been going on every single day, usually in multiple threads at a time, year after year with what you just said being repeated over and over and over. And what has it accomplished? And what has anyone done to try to actually change the CAFE regulations besides complain about them?
As a long time member it’s fascinating to watch the long running obsession BITOG has had with CAFE and how it’s gone on for years with nothing new being said, and how it will go on for many more years to come.
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