Would you use 0W30 instead of 0W20?

[GMBoy]

I thought 0W30 or 5W30 was a better choice than the 5w20 both my Jeeps have stamped on their fill caps. I've been running either 0w30 or 5W30 oil in both of them for several years now.

Absolutely and exactly what I do in our Jeep GJ and Gladiator Rubicon 3.6's - 5w/30 full syn for the win!

 

[ZeeOSix]

This thin oils I think is more political than science.

CAFE drives oil to get thinner and thinner. The science of Tribology shows that the thinner it gets, the less wear protection there is from the viscosity. Of course, there are other ways besides viscosity to mitigate wear, but viscosity is and will always be the primary wear mitigator.

 

[Mephy]

CAFE drives oil to get thinner and thinner. The science of Tribology shows that the thinner it gets, the less wear protection there is from the viscosity. Of course, there are other ways besides viscosity to mitigate wear, but viscosity is and will always be the primary wear mitigator.

Absolutely.

 

[Titan]

My car calls for 5-30w I put 0-40w since it had 150k km now I have 356k km and the engine goes great.
When I went to the mechanic he used to say to me that 0-20w is the right oil for that engine and I would break the car.
This thin oils I think is more political than science.

I'd change your last sentence to: ALL political, NOT science.

 

[Rogueman2016s]

If you’ll sleep better at night run the 30. If you’re not burning and using oil between changes I wouldn’t change a thing. Do you change by time/mileage or oil life monitor?

 

[Mephy]

I'd change your last sentence to: ALL political, NOT science.

 

[chris719]

I'd change your last sentence to: ALL political, NOT science.

Well, new engines specifying 8, 12, 16 grades are specifically designed to be able to withstand those viscosities. Sputter coated bearings, wider journals, piston skirt coatings, DLC cams, etc. I would say it is science being used to solve a problem that you may not agree is a worthy goal. We've already come to some point of compromise, it's just shifting. If not we'd all have been running 5W-50 or 10W-60 for the past 2 decades.

 

[Titan]

Well, new engines specifying 8, 12, 16 grades are specifically designed to be able to withstand those viscosities. Sputter coated bearings, wider journals, piston skirt coatings, DLC cams, etc. I would say it is science being used to solve a problem that you may not agree is a worthy goal. We've already come to some point of compromise, it's just shifting. If not we'd all have been running 5W-50 or 10W-60 for the past 2 decades.

Totally agree with your statements. It is a worthy goal to pursue design changes (both in lubrication as well as mechanically, and even from software/ignition/fuel strategy points of view) that provide measurable benefits. But, the hand-wringing about using 16 vs 20 weights or 20 vs 30 weights or 30 vs 40 weights aren't science-based. While I wouldn't go DOWN in viscosity without a very good reason, a bump up one step isn't going to harm an engine. I'm all for scientifically-based improvements...of which there have been many the past 2 decades.

 

[nicholas]

Okay Folks, I have searched all over, and I didn't see this specific question addressed. (and forgive me for having already sort of explored this question in another person's posted question regarding mixing of the two grades.)

My 2019 Equinox (1.5L turbo engine) specs 0W20 oil. I really believe that 0W30 would be a better choice.
After way too many days of researching all over the 'ole interweb, I have concluded that 0W30 will afford better engine wear protection at normal engine operating temperatures.

Both of them have a "Winter" rating of "0", so until the engine reaches it's normal operating temperature both oil grades are essentially identical. However after the engine reaches normal operating temperature the pictures is quite different. The hot viscosity (100 degrees C) for the 0W20 is between 5.6 and 9.3 centistokes, and the 0W30 is between 9.3 and 12.5. And from all the research I've done, it appears that from a mechanical engineering standpoint, motor oil viscosity of about 10 or 11 cSt is ideal for the vast majority of automotive engines. -for at least the last 40 or 50 years.

For the American auto engines, 10W30 was pretty much the standard from about the 1970's through the 1990's, and then around 2000 5W30 became the norm. But now with the government fuel economy standards squeezing blood out of the industry and engine displacements getting very much smaller (and hopefully with more precisely controlled tolerances) the 0Wxx oils are apparently the new normal.

I find this fact quite interesting: When GM starting using these 1.5L turbo engines in 2016 the oil spec was 5W30. It seems to have magically changed to 0W20 in 2018. I have researched OEM GM part numbers for many of the internal engine parts used in these engines, especially the parts where oil clearances are critical. And from 2016 through at least 2019 the part numbers are identical. Looks to me like the popular reason/excuse given for switching from 30 weight hot to 20 weight being because of so-called tighter tolerances is -V--E--R--Y- questionable. How about this reason: C.A.F.E standards. -all striving for potential fractional increases in mpg.

Until I am shown differently, I am convinced that use of 0W20 is risking long-term engine wear protection.

Certainly, the cold temperature qualities of the the 0Wxx is no doubt a very good thing . On "cold start" the less viscous oil should reach the critical lubricated parts faster, and certainly have much better lubricating qualities than an oil that is way too thick. And granted, it is common knowledge that the majority of engine wear occurs at startup. But the actual wear protection value due to the very low viscosity value of a 20 weight oil when hot,,,, very questionable I'd say.
Maybe more wear hot, but less wear cold will balance out?? I suspect with 0W30 we can have less wear in total.

So, back to my opening question, given the facts before us, would you consider using 0W30 instead of 0W20?

Thanks to everyone reading this !! Looking forward to your comments.

This all depends on your driving style and climate.
Cold weather short trip driving a 20 weight would give better protection.

Hot weather highway driving a 30 might be better depending on the emgine.

 

[kschachn]

This all depends on your driving style and climate.
Cold weather short trip driving a 20 weight would give better protection.

Hot weather highway driving a 30 might be better depending on the emgine.

A lower HT/HS never gives better protection.

 

[Hoster]

For our Subie OB, switched from factory-recommended 0w 20 to 5w 30 mostly due to oil burning. The engine has not blown up In fact, the Japanese manual (for the same engine / car) indicates upto 40 weight oil. Did someone say CAFE?? ;-)

 

[nicholas]

A lower HT/HS never gives better protection.

Minus 20c
A 0w-20 will protect and flow better than a 0w-30.
Anyday

 

[kschachn]

Minus 20c
A 0w-20 will protect and flow better than a 0w-30.
Anyday

-20? Compared to an oil with a 5W winter rating? Nope. Both will pump. And if it pumps it protects. MOFT is high at low temperatures as well. It’s irrelevant if it’s a 20- or a 30-grade.

 

[ZeeOSix]

Minus 20c
A 0w-20 will protect and flow better than a 0w-30.
Anyday

How? Both are rated as a 0W for cold weather start-ups.

 

[OVERKILL]

Minus 20c
A 0w-20 will protect and flow better than a 0w-30.
Anyday

 

[nicholas]

How? Both are rated as a 0W for cold weather start-ups.

Go look at the -35 css for both oils......
It should become clear

 

[nicholas]

View attachment 189466View attachment 189467

 

[OVERKILL]

How? Both are rated as a 0W for cold weather start-ups.

 

[OVERKILL]

 

[kschachn]

Go look at the -35 css for both oils......
It should become clear

Yes it is clear. It’s about pumpability.