CAFE Standards in the US and Oil Grades

[johdirt784]

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?

 

[PimTac]

5w30 is a CAFE oil grade.

 

[MrHorspwer]

Just like we have CAFE, the UK and Europe have CO2 emission requirements. It's not like the US doing anything unique or dastardly versus what is being done on the other side of the Atlantic. Honestly, their way of controlling CO2 emissions is probably more strict, with less loopholes, than CAFE is over here.

Also, would you care to share some of your info. I couldn't get to any explicit owner's manuals without a VIN, but this is straight from Toyota's UK blog.

From https://blog.toyota.co.uk/find-the-right-oil-for-your-toyota


The following table displays the recommended oil specification for all current Toyota models and engine types.

TOYOTA MODEL / ENGINE	RECOMMENDED ENGINE OIL GRADE
Aygo	0W-16
Yaris 1.0	0W-16
Yaris 1.5	0W-20
Yaris Hybrid	0W-20
Corolla 1.2T	0W-20
Corolla 1.8 Hybrid	0W-16
Corolla 2.0 Hybrid	0W-16
Camry	0W-16
C-HR 1.2T	0W-20
C-HR 1.8 Hybrid	0W-20
RAV4	0W-16
GT86	0W-20
GR Supra	0W-20
Prius	0W-16
Prius Plug-in	0W-16
Prius+	0W-20
Land Cruiser (all)	0W-30
Hilux (all)	0W-30
Proace (all)	Please refer to your local Toyota centre
Proace Verso (all)	Please refer to your local Toyota centre

 

[Danno]

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?

Solely to meet EPA MPG numbers.
That 1.5% is huge when you look at total fleet.

 

[johdirt784]

Just like we have CAFE, the UK and Europe have CO2 emission requirements. It's not like the US doing anything unique or dastardly versus what is being done on the other side of the Atlantic. Honestly, their way of controlling CO2 emissions is probably more strict, with less loopholes, than CAFE is over here.

Also, would you care to share some of your info. I couldn't get to any explicit owner's manuals without a VIN, but this is straight from Toyota's UK blog.
[/QUOTE}

Find the right oil | Shell Global

Find the right oil

go.shell.com

Shell is spec'ing out 5W-30 for most of these models in the UK. I have seen the Australian manual for the Corolla and states you can run 0w-16, 0w-20, 5W-20, or 5W-30.

 

[Davejam]

Solely to meet EPA MPG numbers.
That 1.5% is huge when you look at total fleet.

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.

 

[Imp4]

For all the bellyaching I hear around here about CAFE and 0w-20, it never ceases to amaze me that the average age of the US cars is older than it has ever been and the percentage of vehicles using 0w-20 is larger than it has ever been.

The preponderance of cars end their useful life well before engine failure by way of 0w-20 oil spec is a glimmer in anyone's eye.

Are there special circumstances? Yeah.
Are there anecdotes. You bet.
Anecdotes are also not data.

For the person simply trying to drive to work in the morning and tool around on the weekends (including weekend warrior towing), OEM spec'd 0w-20s are completely reasonable.

 

[OilReport99]

For the person simply trying to... [insert your favorite activity]

Typical collective mentality. You, or whomever, choose what the person "needs".

 

[Imp4]

Typical collective mentality. You, or whomever, choose what the person "needs".

Ugh, no straw man arguments please, thanks.

I'm not choosing anything for you. I'm just stating what works. Pick whatever you want.
If you think my conclusion is wrong, show me the data to back up your claim.
Show me all the failures.
Show me the wide swath of manufacturers that spec'd 0w-20 originally and then went back to a previous specification.

Its easy to say 'dont generalize me, you don't know my specific situation'. You'd be correct that i don't know your specific situation. I'm not addressing it either. I'm speaking to the preponderance of the motoring public and I'm making a statement about what is fit for the purpose.

 

[OilReport99]

I'm not addressing it either. I'm speaking to the preponderance of the motoring public and I'm making a statement about what is fit for the purpose.

Motoring public? You’re at it again?

 

[wemay]

Some 2.6 HTHS oils protect just as well as some 3.5 HTHS against wear...

(These can be compared as they are both VW Approvals. In full disclosure though, VW504.00 currently protects best and is 3.5 HTHS)

404 - Page Not Found - Lubrizol

404 - Page Not Found

www.lubrizol.com

 

[92saturnsl2]

I'm of the opinion that 5w-30 offers better protection under a lot of driving conditions than the thinner grades being pushed in the interest of maximizing fuel economy. That said, engines using 0w-16 / 0w-20 will almost universally outlast the vehicle, so the argument is somewhat moot.

I typically use 30 weights in vehicles that spec 5w-20, but if I find an oil on sale that happens to be a 20 weight, I'm using it and not giving it a second thought.

 

[OilReport99]

Some 2.6 HTHS oils protect just as well as some 3.5 HTHS...

CAFE Standards have nothing to do with protection.

 

[OilReport99]

show me the data to back up your claim.

The only claim I made is explicitly stated in my post. That is, that your post is a typical example of a collective mentality. The data is your post.

 

[wemay]

CAFE Standards have nothing to do with protection.

The argument by many here has been that you give up protection for better fuel economy by using a 0W-20 vs a 5W-30 etc.

 

[PimTac]

The argument here has always been that you give up protection for fuel economy.

That’s the argument and the key word is “argument”.

 

[OilReport99]

The argument by many here has been that you give up protection for better fuel economy by using a 0W-20 vs a 5W-30 etc.

I believe the argument has more to do with the compelling nature of the [mandatory] fuel economy.

 

[blingo]

Maybe give up some power for recovery of lost protection? I'd even say Lambda 1 all the way if it cost 60% of nominal output. Even better, let's have it all!

 

[PimTac]

Maybe give up some power for recovery of lost protection?

The newer engines are extracting more horsepower per liter than ever before on 20 grade oils.

 

[OilReport99]

The newer engines are extracting more horsepower per liter than ever before on 20 grade oils.

That sounds like the "It is what is is" fallacy. The newer engines are extracting the horsepower they extract on the oils they're mandated to use.
Is there any evidence that they cannot extract more horsepower on heavier grades? And if there is...what does it have to do with protection for the 'Motoring Public'?