CAFE Standards in the US and Oil Grades

VW tries their best to convince you of that as we discussed in another thread, but of course they end up saying that warranty will be denied if the oil you used caused the failure. No 504 00 oil in this application will cause engine failure, plain and simple. If anything it will help to prevent one.

Yep, the part in bold will always be the case. I have zero worries that going up one grade in viscosity (5W-20 to a 5W-30) will cause any engine issues, and agree it will help actually give a bit more protection.
 
The owner's manuals "recommend", they don't "demand" that a specific oil viscosity is used. And I've never seen any owner's manual statement that says warranty would be denied if a different oil viscosity besides what was "recommended" was used.
I just don't see how a HD truck that is spec'd for 15w40 can be filled with 0w16, then haul a massive load way up the mountain and worked super hard, can have adequate engine protection and warranty honored. I'm probably confused about the API spec or something, it happens.
 
I just don't see how a HD truck that is spec'd for 15w40 can be filled with 0w16, then haul a massive load way up the mountain and worked super hard, can have adequate engine protection and warranty honored. I'm probably confused about the API spec or something, it happens.

Well, in this case if someone ran 0W-16 in a HD truck that called for 15W-40, and the engine suffered damage (which it probably would if pushed hard) as a result, then the manufacturer would most likely deny warranty if they knew 0W-16 was used.

At this time, I think pretty much small engined 4-cly passenger cars are specifying 0W-16.
 
I have seen this come up time and time again, but after looking at owner manual information from around the world, on the same car, with the same engine - the US specs the lightest oil and even use words like "you can use this oil, but switch back immediately." Even Scotty Kilmer claims that if you don't use a lighter (0W-16) in your car with variable valve timing, you can damage your engine. As I have seen here, the less viscous weights are driven by the CAFE standards in the US and there is research from the late 90s that was collated by ORNL that 5W-20 is 1.5% more fuel efficient as compared to 5W-30. Even on a hypothetical car that is rated at 30 mpg, this would result in an observed efficiency of 30.45 mpg when switching to the lighter weights. Most of us would never notice the difference.

Here are some engines that I have found different oil specs for the US as compared to the rest of the world:
2ZR-FXE - GenIII Prius (2010 to 2015) US 0W-20; UK Corolla Hybrid 5W-30
M20A-FKS - 2019+ Corolla US 0W-16; UK 5W-20/30
2GR-FKS - 2017+ Tacoma US 0W-20; UK 5W-30
A25A-FKS - 2018+ Camry US 0W-16; UK 5W-30

1) There is absolutely no way that a manufacturer makes a different engine in the US as compared to the rest of the world. This would be cost prohibitive and a supply chain nightmare.
2) Even if you you used the heavier weight oil, you definitely wouldn't damage your engine - the manufacturer has obviously tested multiple grades for wear, longevity, and efficiency.

My guess is that you could use 5W-30 in practically 90% of passenger cars in the US. So why is there such an attitude of "USE WHATS IN YOUR OWNER'S MANUAL, OR ELSE!!!" and why is the language so strong in the US manuals?

Do other countries spec heavier oil for lower emissions?

The strong language in owner's manuals is due to government regulation. Manufacturers are required to do everything they can to get you to use the oil used for the EPA certification of that vehicle. The brainwashing was easy and largely effective. Thus the fantastic stories of using a 1 cSt thicker oil will destroy your engine.

Attached is a copy of the letter from the EPA to Ford laying out the requirements of using a thinner viscosity to help meet CAFE mileage goals.
 

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The strong language in owner's manuals is due to government regulation. Manufacturers are required to do everything they can to get you to use the oil used for the EPA certification of that vehicle. The brainwashing was easy and largely effective. Thus the fantastic stories of using a 1 cSt thicker oil will destroy your engine.

Attached is a copy of the letter from the EPA to Ford laying out the requirements of using a thinner viscosity to help meet CAFE mileage goals.
I think you add to and read too much into it. Nowhere does it say Ford is wanting a thinner oil due to CAFE. If something is certified, that means it is just that something only. So the book has to be worded to reflect that. That's all it is, no government regulation scheme, no nothing is there. Certified is the key word. Sounds reasonable to me. We are left to our own engineering staffs to decide if Ford is right or wrong with the thinner oil. Where Ford really gained mpg to meet CAFE was using those small turbocharged engines. I can't belive the Ford 2.3 engine in a production Explorer is rated 28 highway and puts out 300 hp with a 0-60 of around 6.2 seconds. But I think their main reason is to sell more Explorers. Who doesn't like the sound of those mpg and power numbers? Like means trade the old car in and get the new one, which is what Ford exists to do.
 
Mr. Farnsworth. Did you read the letter to Ford/Honda in the post above yours?

Apparently not. These days, all manufactures are striving for as many CAFE credits as possible, and using the thinnest oil possible is one way they do it.
 
It's pretty much spelled out in the letter above. Meeting EPA standards is an endless goal for manufacturers that sell in the US.
 
I just don't see how a HD truck that is spec'd for 15w40 can be filled with 0w16, then haul a massive load way up the mountain and worked super hard, can have adequate engine protection and warranty honored. I'm probably confused about the API spec or something, it happens.

Yeah, well, you could say the same in regards with a 5W-30 that doesn't have the appropriate manufacturer HDEO spec's. The bigger issue would be that the 0W-16 would lack the soot control additives and the typical HDEO additive package since it is a gasoline oil. Then again, there is also the possibility that the 0W-16 would irrevocably damage the engine, but not destroy it before the typical OEM warranty was up...

My guess is that a 0W-16 HDEO oil could be formulated for, say, a special cold weather diesel oil but I won't deny that I would be hesitant to use it. In any case even HDEO oils are trending thinner in at least some applications. I once drove a Caterpillar off-road articulated end dump (a "uke"), and was shocked to find that it recommended a 10W-30 HDEO and even synthetics like 5W-30 in very cold climates. Is Cat worried about CAFE? IDK, maybe, but I doubt it!
 
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Well, in this case if someone ran 0W-16 in a HD truck that called for 15W-40, and the engine suffered damage (which it probably would if pushed hard) as a result, then the manufacturer would most likely deny warranty if they knew 0W-16 was used.

At this time, I think pretty much small engined 4-cly passenger cars are specifying 0W-16.

Last time I checked, I think there are only a couple engines calling for 0W-16, one was a Toyota 2.4L the other a Honda hybrid...
 
The strong language in owner's manuals is due to government regulation. Manufacturers are required to do everything they can to get you to use the oil used for the EPA certification of that vehicle. The brainwashing was easy and largely effective. Thus the fantastic stories of using a 1 cSt thicker oil will destroy your engine.

Attached is a copy of the letter from the EPA to Ford laying out the requirements of using a thinner viscosity to help meet CAFE mileage goals.
The fact that the EPA mandated that they can't even use the word 'preferred' is definitely the cause for the language in US owner manuals. Thanks for the post!
 
Is there any long term data for the 0w20 grade being used by BMW for some of their cars? My brother's x3 M40i calls for a 0w20. Surprised a car with that much power, and being German, calls for a 20 grade.
 
The fact that the EPA mandated that they can't even use the word 'preferred' is definitely the cause for the language in US owner manuals. Thanks for the post!
Yeah, coupled with the fact that the manufacturer has to ask to use that oil to be graded by and standard set by them is interesting. They then in turn stipulate all those specifics. Ford just about get around it partially in their Mustang manuals for the 5.0 in saying you can use 5w30 to 5w50 for track use, then immediately change back to 5w20 for the road....
 
You make a good observation. The 4.0 in my 4Runner, for example, is specified for up to 20w-50 elsewhere in the world. 0w-20 here in the States.

For US vehicles, the owner's manual is required to list only the oil used in mpg testing. Some manufacturers get around this by saying a thicker oil may be required for adequate lubrication in heavy duty use. Words are mine, but the concept is in many manuals.

In some countries they specify thinner, in some they don't.

Agree that many or most vehicles vehicles will be totally fine with a 20 grade. However there is the fact that Ford moved from a 20 back to a 30 grade in their truck line.

The 1GR-FE is One of the classic examples of CAFE mandating thinner oils. Because it is so ubiquitous around the world in Toyota’s lineup we have a lot of examples.
In Australia , Toyota provides an “old school” temperature chart with NUMEROUS options dependent on cold temps.

In the US Toyota gives you 5w30 (Or 0w20 depending on vehicle10w30 in pinch but switch back immediately).

in Australia, the temp chart says max temps for 5w30 should be around 80 or so. In the US they say 5w30 all temps.

I highly doubt Toyota is making wholesale changes to the engine in the US “requiring” 5w30.

In the warmer climates of the US I don’t see why one couldn’t run a xw40 or xw50 year round.

Edit: I have some DELO XLE 10w30 laying around I’ve been tempted to use, but ultimately I see numerous examples of High Miles Tacoma’s with 300k- 400k plus Using 5w30.

I think for most engines it just doesn’t really matter.
 
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Found another example of the same engine family having very broad oil specifications described in the owner's manual - Third generation (BM, BN) Mazda 3

US Manual - "Mazda Genuine 0W-20 Oil and Castrol® 0W-20 Oil are required to achieve optimum performance."

Vehicle calls for explicit use of 0W-20 in the US and doesn't suggest any alternatives (unless you are in Mexico; 5W-30) and pretty much tells you to use whatever you want in the UK and AUS - pages 576 and 737

"Engine oil viscosity, or thickness, has an effect on fuel economy and cold-weather operation (starting and oil flow).
Low-viscosity engine oils can provide improved fuel economy and cold-weather performance.

When choosing an oil, consider the temperature range your vehicle will operate in before the next oil change.
Then select the recommended viscosity from the chart."

 
Haha, that's old school in style and about as loose as i've ever seen in a recent owners manual :D - use oil, look at this chart, pick an oil that suits how/where you'll drive it :D
 
The strong language in owner's manuals is due to government regulation. Manufacturers are required to do everything they can to get you to use the oil used for the EPA certification of that vehicle. The brainwashing was easy and largely effective. Thus the fantastic stories of using a 1 cSt thicker oil will destroy your engine.

Attached is a copy of the letter from the EPA to Ford laying out the requirements of using a thinner viscosity to help meet CAFE mileage goals.
Illuminating, thanks
 
This will be in US owner's manuals soon - per CAFE mandate.

It will say: Stare into this image and repeat the following statement.

"You Must Use 0W-16 or 0W-20 Motor Oil".

hypnotizing.gif
 
But even more-so when you consider the whole country of vehicles.
Lowering vehicle emissions by that much is significant whether or not you have the ability to perceive it.
Maybe the ability to keep ICE on the road longer before regulators shut it down. OMG, what would become of this website? The Tesla car wash guy … c’mon man, I need to change and talk oil, I just do !
 
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