CAFE Standards in the US and Oil Grades

[ZeeOSix]

That you don't know what you are talking about...just a guess. As someone who has seen more JD vehicles than most in the US...yes, they look pretty good, but range from almost spotless to sludged up. Because their cars are practically forced off the road after 7 years (and why they are exported to NZ), almost zero maintenance is done. Yes, they look far better than the same year car in NZ, and usually are, life is tough here and cars get used hard, but almost no maintenance will have been done.

My comment in post #227 is true ... the engines in Japan don't make it many mile before being replaced ... regardless of the reasons why. I really don't believe everyone in Japan doesn't do any maintenance on their cars and just treat them as "disposable".

Insider Secret: Why Japanese Used Cars Have Low Mileage - Expert Maintenance and Buying tips - Carused.jp Blog

These days, more and more ... Read more

carused.jp

why do engines in japan get replaced at low miles - Google Search

 

[Motu]

We've been importing, and I've been working on these things for over 30 years - you haven't got a clue.

 

[ZeeOSix]

We've been importing, and I've been working on these things for over 30 years - you haven't got a clue.

Sure ... all the info on the 'net on why cars in Japan are retired early are all false. 😂 Why don't you tell us all the real story.

 

[tolian21]

No one has any proof that running one or two grade thicker oil than recommended will cause any harm to the engine.

 

[Topnotchuk]

Insignia B check from 2018 and beyond.

Insignia B check from 2018 and beyond.

Things are a little different now under the Psa hood...... More mind boggling I'll stick with my last of the GM Astras

 

[alcyon]

5w30 is a CAFE oil grade.

5W-30 was the previous darling of CAFE in the 90s. The new darling is 0W-20 and 5W-20.

 

[4329]

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?

This is from my Hyundai owners manual in Australia and clearly states that the lower viscosity is for fuel saving.

: For better fuel economy, it is recommended to use the engine oil of a viscosity grade SAE 5W-20

Opinion only, I would rather have greater engine protection than save fuel. The manual also states to select the viscosity based on the temperature the vehicle is operating in allowing the use of 5w-30, 10w-30 and 15w-40 depending on temperature.

 

[Direct_Rejection]

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?

This subject has been discussed ad nauseam on BITOG.

Typically, "Thickies" troll any discussion, any mention even, of very thin oil, with voluminous, incessant posting that is off topic.

Maybe you and MrHorspwr would like to stop distorting the truth by correcting your huge, glaring omission re YarisCross.

The YarisCross (M15A FKS) has engineering and specs that yield a recommendation of 0W8 motor oil, and since it is not sold in North America, is thusly not subject to CAFE, or NA fuel/driving conditions.

As I drive the similarly engineered 2.0L 4 cylinder version of Dynamic Force engines (M20A FKS) in a NA Lexus UX 250h, as opposed to a Corolla Hybrid , I have/will be making informed decisions accordingly.

 

[ChrisD46]

In the case of the notorious Hyundai 2.4L Theta II GDI engine : It was CAFE tested with 5W20 however due to questionable rod bearings the Hyundai dealers all switched to or recommend 5W30 weight oil to give those rod bearings more film strength cushion . Since 5W30 and 10W30 were already allowed in the OM - this was an easy call for Hyundai to help counter a design flaw . After the factory fill was dumped , I switched over to 5W30 and never looked back (even though oil cap stamp says "5W20".)

 

[PimTac]

5W-30 was the previous darling of CAFE in the 90s. The new darling is 0W-20 and 5W-20.

The new darling is 0w-16.

 

[billt460]

....... 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.......

This is simply NOT TRUE with Toyota. It does however have some merit with the Chrysler Jeep 5.7 L, HEMI V-8. My 2018 Toyota Camry 2.5, 4-Cylinder allows 0W-20 to be used. And also say's right in the manual that, "An oil with a higher number, (higher viscosity), may be better suited in severe load, high speed conditions".

The manual for my 2015 Jeep Grand Cherokee, (5.7 L, HEMI V-8), say's no such thing. It does say that the use of any other oil viscosity other than 5W-20 can cause the VVT, (Variable Valve Timing), and the MDS, (Multi Displacement System), to malfunction. On the Jeep forum several guys have posted that the vehicle threw codes because the wrong viscosity oil was used. (Too high viscosity).

So it would appear, (without further research), that the Toyota VVT system is much more tolerant of different viscosity oils, than the either the VVT or MDS system in the HEMI Jeep is. The Toyota does not have MDS.

 

[kschachn]

This is simply NOT TRUE with Toyota. It does however have some merit with the Chrysler Jeep 5.7 L, HEMI V-8. My 2018 Toyota Camry 2.5, 4-Cylinder allows 0W-20 to be used. And also say's right in the manual that, "An oil with a higher number, (higher viscosity), may be better suited in severe load, high speed conditions".

The manual for my 2015 Jeep Grand Cherokee, (5.7 L, HEMI V-8), say's no such thing. It does say that the use of any other oil viscosity other than 5W-20 can cause the VVT, (Variable Valve Timing), and the MDS, (Multi Displacement System), to malfunction. On the Jeep forum several guys have posted that the vehicle threw codes because the wrong viscosity oil was used. (Too high viscosity).

So it would appear, (without further research), that the Toyota VVT system is much more tolerant of different viscosity oils, than the either the VVT or MDS system in the HEMI Jeep is. The Toyota does not have MDS.

Plus on the Toyota vehicles the computer does not monitor the response signature so that a code can be generated. It's not part of their CAFE award requirements.

 

[billt460]

I'm not so sure about the actual mechanics of the HEMI being that viscosity sensitive either. I say that because while the 5.7 HEMI "requires" 5W-20, the larger displacement 6.4 HEMI that comes standard in many models of the RAM pickup, "requires" 0W-40. Are the VVT and MDS systems different between the 2? I can't find anything that say's they are.

 

[MaDMaXX]

The 'VVT' in 2000's Fords is sensitive to oil viscosity too, but things like the Triton 3v have enough of their own problems anyway. The Borg Warner system used in 2011+ motors isn't dependant on oil pressure so it doesn't matter in those.

Remember that CAFE approval/testing means they submit for one oil viscosity and have their MPG rating based on that - CAFE's stipulations say they cannot state use of any other oil viscosity for that vehicle, hence why there are no longer ranges being stated in the owners manual, and only one grade being touted.

 

[OVERKILL]

I'm not so sure about the actual mechanics of the HEMI being that viscosity sensitive either. I say that because while the 5.7 HEMI "requires" 5W-20, the larger displacement 6.4 HEMI that comes standard in many models of the RAM pickup, "requires" 0W-40. Are the VVT and MDS systems different between the 2? I can't find anything that say's they are.

The systems are identical.

User Clevy ran M1 0w-40 in his 5.7L and was only able to get the viscosity code once, and it was like -40C. You have to really stray off the reservation to trigger the system due to the necessarily generous range applied to the system.

The system infers viscosity from oil pressure and oil temperature. It has to be a pretty broad range to account for both wear and manufacturing variances between vehicles. However, if you put something very heavy in there, it will trigger a code because you'd managed to push it outside what it considers "normal" for oil pressure at that temperature.

The mechanisms themselves are of course not sensitive to viscosity, it's a programming decision made to deter people from putting "good old days" oil in the engine, like 20w-50 I suspect.

 

[kschachn]

Currently some engines use the VVT response signature to detect “out of grade” oils, next up will be similar signatures from computer controlled variable volume oil pumps.

Just like with the VVT nothing is going to break but it will be another nanny system to help ensure the grade used for the initial certification continues to be used.

 

[OppositeLocK]

This is simply NOT TRUE with Toyota. It does however have some merit with the Chrysler Jeep 5.7 L, HEMI V-8. My 2018 Toyota Camry 2.5, 4-Cylinder allows 0W-20 to be used. And also say's right in the manual that, "An oil with a higher number, (higher viscosity), may be better suited in severe load, high speed conditions".

The manual for my 2015 Jeep Grand Cherokee, (5.7 L, HEMI V-8), say's no such thing. It does say that the use of any other oil viscosity other than 5W-20 can cause the VVT, (Variable Valve Timing), and the MDS, (Multi Displacement System), to malfunction. On the Jeep forum several guys have posted that the vehicle threw codes because the wrong viscosity oil was used. (Too high viscosity).

So it would appear, (without further research), that the Toyota VVT system is much more tolerant of different viscosity oils, than the either the VVT or MDS system in the HEMI Jeep is. The Toyota does not have MDS.

Interesting. Probably the safest thing to do is follow the owners' manual and just change your oil more frequently than suggested.

 

[ZeeOSix]

The YarisCross (M15A FKS) has engineering and specs that yield a recommendation of 0W8 motor oil, and since it is not sold in North America, is thusly not subject to CAFE, or NA fuel/driving conditions.

Japan has their own "CAFE" type regulations, which looks to be even more stringent than the CAFE here.

 

[Direct_Rejection]

Japan has their own "CAFE" type regulations, which looks to be even more stringent than the CAFE here.

JASO is King.

 

[ZeeOSix]

Remember that CAFE approval/testing means they submit for one oil viscosity and have their MPG rating based on that - CAFE's stipulations say they cannot state use of any other oil viscosity for that vehicle, hence why there are no longer ranges being stated in the owners manual, and only one grade being touted.

Some US owner's manuals still give some room to use a different viscosity beside the "recommended" viscosity. But you are right that you will never find the old fashioned ambient temperature range graph showing 3 or 4 oil choices depending on the ambient temperature range, but still used in other countries that the same car is sold in, as proved many times.