Would you use 0W30 instead of 0W20?

Messages
31
Location
Wyoming
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.
 
Messages
2,337
Location
South Carolina
Yes, the old 10cSt rule was popular 20 years ago (and beyond) but oil, not so much engines, has changed so much that the old rules generally don't apply to our grocery getters. I'm using 0w-20 in my 2000 4Runner (Toyota recently approved) and I don't feel I'm sacrificing longevity.

The 10cSt rule has given way to the HTHS spec now. Engine testing has proven that an HTHS of 2.6 is the minimum which is the bottom of the scale for 0/5w-20.
 
I’m not commenting on the 20 vs 30 thing as I’ll let the others carry on with that old tune.
However to discuss what the viscosity of a 0w20 vs a 0w30 is at very low temps, say -30 C look at its MRV data. You’ll find 0w20 will typically have a lower MRV viscosity than a 0w30. No huge difference but they won’t be identical. Also, the 0w30 oils are often Euro type oils and have a higher viscosity than North American xw30 oils at 100 C, so not only is their viscosity higher than 0w20, it’s typically higher than a North American 5w30 at 100 C. Welcome to Bitog.
 
Last edited:
Messages
17,034
Location
Upper Midwest
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.
Plus out of that whole tome you keep using the term tolerances when it is clearances. Your "many days of researching all over the 'ole interweb" must have missed that somehow.

And most wear does not occur at startup, even if it did it isn't because of the winter rating of the oil. Oil is not too thin at startup and as far as temperature is concerned there will be more than adequate film thickness. Common misconception, not "common knowledge". Oil that is too thin to provide an adequate MOFT is what causes wear in your scenario.

And it depends on the temperature whether two oils with the same winter rating will be "essentially identical" or not. The cold temperature qualities of an oil with a 0 winter rating will only be apparent at extremely low temperatures, far below that which most people attempt to start a car. For everyone else it makes no difference at all. None.

And it isn't magic that thinner grades were listed. It was a reasoned decision based on adequate MOFT under typical circumstances. Honda used the word "acceptable". That is what it is. Not magical.
 
Messages
4,822
Location
Southeast
I’ve experienced different engine behavior based on the vehicle than the oil. if the engine runs well on 20wt, I’m all for it. If there’s evidence suggesting that motor should be on a heavier oil, then do that. my Lexus has pin slap, so it gets a 30 now. My truck is known for potential chain guide wear, so it went from 5-30 to 10-30. The Hondas in our family all stick with 20 wt happily. So first, I wouldn’t change unless you have a reason meaningful to you.

my only other thought is that 0-30 has a wide spread in viscosity. My thinking may be dated, but that requires more viscosity modifiers to do. I’d rather have fewer modifiers and more base oil. That would steer me to consider a 5-30.

m
 
Messages
35,625
Location
NY
Why 0w30 instead of 5w30? I only ask because there are so many 5w30 choices by comparison and most 0w30 do not perform any better.
That's true. But in my case years ago I had a cousin who lived in the Adirondacks and I spent weeks at a time during the winter at his house. There were times I'd get up in the morning and would see temps as low as -35F. He told me he saw it even colder than that on occasion. 0W30 was the better choice imo.
 
Messages
195
My cars are spec’d for 0w20 but I have always used 0w30 and never had any problems.

Not sure if it will decrease engine wear but I am more sure it won’t hurt it either.

when my cars were under warranty ( dealer ) I would bring my own oil ( but took the labels off and wrote 0w20 with a marker ) and tell them it’s 0w20 and never had them question it.
 

57_Chevy_Thunder

Thread starter
Messages
31
Location
Wyoming
Great responses ! Thanks. Many good aspects to consider. Sorry for confusing the terms clearances and tolerances. In the year range I cited, the oil clearances were the same. However a weak argument could be made that the Quality Control Dept could have hopefully tightened up their tolerances. -ie allowing less variation on allowable oil clearances. -weak I know,, but just grasping at straws.

Good points to consider exactly what range of ambient temperatures are realistically expected in each person's situation. And very honestly, as Ignatius points out, in my situation where the vehicle stays in a heated garage when not in use, there is little doubt a 5W30 work work perfectly well. Especially, I might add since that is exactly what the 2016 and 2017 malibu with the same engine had specified.

Very good thought meep, about the wider spread of the 0W30, something I had also wondered about. Generally speaking, to my thinking, the less VI improvers that have to be used the better. And granted it may be that the quality of them is high enough now that they don't have near the HT/HS problems that used to be the case. (my UOA reports would probably show the viscosity loss, it was happening,,,) The more I looked into it, the more apparent it became that the 0W30 finishers are using a high quality synthetic base oil. And apparently some of the Gas-to-Liquid synthetic base oils now require absolutely no VII's, depending on the grades they are building. Pretty neat I'd say!

And yes farrarfan1, the min viscosity for the 20W hot most certainly is 6.9cSt. I have no idea how I got that wrong,,, my appology.
To 4WD, yes it certainly is Gen2Dexo1, plus ILSAC GF-6, and API SP, which all seems good to me.

And to those of you who are already using 0W30 (and even 5W30) in your specific applications, THANK YOU for sharing that good information. It sure seems like a person is pretty safe making small changes for specific reasons. -probably not likely to have any problem, but rather have at least a small benefit.

And sadly I have to admit, "Yes, I could just as well use a quality 0W20." -probably never be able to detect any difference.
But good grief, why not accept the challenge of exploring a good rabbit hole once in a while !!

Thanks again to all, and I'll keep checking back for more responses.
 

57_Chevy_Thunder

Thread starter
Messages
31
Location
Wyoming
Oh, sorry I also wanted to mention that I also read and appreciate the thick vs thin thread. Overkill really nailed it with his great information !!
It is totally logical in my mind that to go up only one step on the hot viscosity rating should be very safe and makes good sense.
 
Messages
24,260
Location
Dallas,Tx USA
Plus out of that whole tome you keep using the term tolerances when it is clearances. Your "many days of researching all over the 'ole interweb" must have missed that somehow.

And most wear does not occur at startup, even if it did it isn't because of the winter rating of the oil. Oil is not too thin at startup and as far as temperature is concerned there will be more than adequate film thickness. Common misconception, not "common knowledge". Oil that is too thin to provide an adequate MOFT is what causes wear in your scenario.

And it depends on the temperature whether two oils with the same winter rating will be "essentially identical" or not. The cold temperature qualities of an oil with a 0 winter rating will only be apparent at extremely low temperatures, far below that which most people attempt to start a car. For everyone else it makes no difference at all. None.

And it isn't magic that thinner grades were listed. It was a reasoned decision based on adequate MOFT under typical circumstances. Honda used the word "acceptable". That is what it is. Not magical.
Excellent post kschachn! (y)
 
Top