Would you use 0W30 instead of 0W20?

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1,405
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Maryland
Screenshot_2021-02-25 5W-30 Shell Motor Oils Comparison.jpg
 
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1,565
Location
St. Louis, MO
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.

What lead you to this conclusion?

You do know that the 0 in 0W-20 or 0W-30 won't matter until the temperature of the oil is 0F or lower. At temps that low 0W-20 and 0W-30 are the same viscosity. When your engine reaches operating temperature, that's a different story. Myself personally, I would stick with whatever the manufacturer recommends.

There were probably internal changes to the engine from 2016 to 2018 that you are probably not aware of.

At the end of the day, the engine probably isn't going to suffer from using 0W-30 over 0W-20. GM is probably glad you're at least changing the oil regularly.

At the end of the day, your "feelings" have zero bearing on which viscosity oil is best for your engine, stick with what the manufacturer recommends.
 

57_Chevy_Thunder

Thread starter
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31
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Wyoming
To walterjay, thanks for sharing the Shell Oils chart.

To Silver, well I don't know. From what I remember reading about HTHS, it involves molecular shearing, which reduces the oil's viscosity index?
Maybe someone else can answer that one.

I am finding it quite educational as to how many factors are involved in motor oil engineering.

Yes, I sure do overthink some things. I usually find it to be good mental exercise, but when it reaches the point where no further useful material is likely to received, it is time to just let it go, and move on.

Thanks to all who continue to submit useful material.
 
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27,184
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PNW
From what I remember reading about HTHS, it involves molecular shearing, which reduces the oil's viscosity index?
Maybe someone else can answer that one.
An oil with more viscosity index improvers (ie, an oil with a larger VI number) may have a lower HTHS than another oil of the same viscosity because some viscosity is lost when the VI improvers shear. And those oils tend to permanently shear down more with use because it's the VI additives that shear (get chopped up) and reduce viscosity. Of course, some engines shear oil more than others. But the bottom line is if you're comparing oil's HTHS at 150C, then a higher HTHS is better.
 
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1,204
What lead you to this conclusion?

You do know that the 0 in 0W-20 or 0W-30 won't matter until the temperature of the oil is 0F or lower. At temps that low 0W-20 and 0W-30 are the same viscosity. When your engine reaches operating temperature, that's a different story. Myself personally, I would stick with whatever the manufacturer recommends.

There were probably internal changes to the engine from 2016 to 2018 that you are probably not aware of.

At the end of the day, the engine probably isn't going to suffer from using 0W-30 over 0W-20. GM is probably glad you're at least changing the oil regularly.

At the end of the day, your "feelings" have zero bearing on which viscosity oil is best for your engine, stick with what the manufacturer recommends.
What i usually read around here - regarding oil - is that the manufacturer recommendation aren’t always in the best interest of the person who owns the vehicle...that the manufacturer needs to meet cafe regulations in this country and therefore their recommendations aren’t necessarily what’s best for your engine long term (for beyond a warranty in which you could probably run olive oil without worries).

And that in some countries that very same engine will run a different weight oil?

For instance, I own a 2016 Toyota Avalon with the V6...it says run 0w20 and I do. But I do wonder if a 5w30 would offer better protection. I’ve run into people that laugh when I tell them I use 0w20, as they say...I’d never run 0w20 in an engine. So, it is certainly something that people wonder about and debate.

I used to own a 2018 Silverado with the 5.3 and yet again, it required 0w20, yet on the forums there were a lot of people running 5w30. And I was experiencing some oil consumption on the 0w20 but never switched to the 5w30 before I traded it in with 50,000 miles on it.

Then there is the crowd that says to bump the viscosity up to 5w30 when you reach 100,000-120,000 miles because at that point your engine has experienced some wear and the tolerances are now greater. Which makes some sense to me. And then there are people now claiming they have gone over 200-300k on the 0w20 without issue. So, no one seems to know.
 
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185
Location
North NJ USA
there are also a lot of 5th gen 4runner owners on here who also run 0w30 or 5w30 rather then the spec 0w20. many have noticed in 1GR engine 0w20 tends to make the engine sound louder. but also toyota states you can run other oils in the manual. imo 0w30 or 5w30 over any 20wt any day.
 
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1,204
there are also a lot of 5th gen 4runner owners on here who also run 0w30 or 5w30 rather then the spec 0w20. many have noticed in 1GR engine 0w20 tends to make the engine sound louder. but also toyota states you can run other oils in the manual. imo 0w30 or 5w30 over any 20wt any day.
I just read my manual, it says 0w20 and that if i must use 5w20, to change it to 0w20 at the next oil change.

Yet I just don't believe this^^. I have enough 0w20 to last me another 4 oil changes...I'm going to switch to 5w30 after that. I'll be at around 87,000 miles of easy highway driving by then. I'm not worried about fuel economy - this car can average 30 mpg without even trying - I'm not concerned about lousing .10 of that.

And I know I'm putting too much thought into this, I just don't care...it's an oil website for god's sake. lol
 
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17,034
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Upper Midwest
I just read my manual, it says 0w20 and that if i must use 5w20, to change it to 0w20 at the next oil change.

Yet I just don't believe this^^. I have enough 0w20 to last me another 4 oil changes...I'm going to switch to 5w30 after that. I'll be at around 87,000 miles of easy highway driving by then. I'm not worried about fuel economy - this car can average 30 mpg without even trying - I'm not concerned about lousing .10 of that.
They aren't stating that in the manual for a technical or mechanical reason.
 
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1,204
They aren't stating that in the manual for a technical or mechanical reason.
Yeah, I think you’re right, I think it’s just for fuel economy quite honestly. I’m at 65,000 miles now...car runs great, no ok consumption, nothing. Using 0w20 the whole way on 5,000 mile intervals.

But I have run a vehicle on 0w20 for a long while...everything was great until I started hitting the 150,000 mile mark. Not sure if it was because I tried some extended drain (8,000 miles or so), or because it was a direct injection engine, but it started using oil at 150k and started drinking it around 170,000 miles. So I’m a little paranoid now I guess. Lol
 
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15,870
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N.H, U.S.A.
Okay Folks, I have searched all over, and I didn't see this specific question addressed.

My 2019 Equinox (1.5L turbo engine) specs 0W20 oil. I really believe that 0W30 would be a better choice.

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.
That is incorrect. AT KV40 the 20 grade will be 45cSt and the 30 grade will be 63cSt - and that is 104 deg. F Expect to see an even GREATER divergence as fluid temperature drops. -Ken

How about this reason: C.A.F.E standards. -all striving for potential fractional increases in mpg. There is some of that in there - Ken
And granted, it is common knowledge that the majority of engine wear occurs at startup. Not usually due to high oil viscosity; there is greater wear occurring under high loading at high rpm - that can be a case for greater film thickness and robust and active EP /AW additives - Ken
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. You could rightly anticipate less margin of safety from overloading at higher oil sump temperatures - but do you ever go up to that line? - Ken
So, back to my opening question, given the facts before us, would you consider using 0W30 instead of 0W20? No, Not unless you often start you vehicle in temperature below -20 deg F. A 5W-Xx multigrade should be adequate, and may be more robust at any given price point v. a 0W-Xx. Realize that you do not have to proceed in an "all or nothing" fashion, you can boost your sump viscosity by substituting in just one quart of a one-step higher grade ( same brand same product line). Or you could try M1 ESP <or> a similar Castrol Product and be afforded the highest "comfort level". Proceed with caution, as I have found MANY engines designed for low HTHS perform sluggishly with high HTHS lubricants, and this can have a cascading effect on emission and other drivetrain parameters and operation. - Ken

Thanks to everyone reading this !! Looking forward to your comments.
 
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57_Chevy_Thunder

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31
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Wyoming
Absolutely outstanding response "Ken" !!! Thank You !!! This is exactly the caliber of material I was hoping to find here on BITOG.

Hey "doublebase", I just love your last sentence on your reply today at 1:57: " And I know I'm putting too much thought into this, I just don't care...it's an oil website for god's sake. lol" What a totally fitting statement. Its too obvious that I also resemble that remark !!

And to all the last seven responses, Thank You Everyone for your very respectful replies.

And that also goes for ALL of you who choose to be respectful to us who are sincerely brainstorming the topic.
We are sharing what we have discovered so far and what our personal experiences have been.

And speaking for myself, I come to this forum with no hidden agenda. I offer my sincere apology to anyone who I may have unintentionally aggravated or offended. I hope to always be honest and polite, and to respect EVERYONES opinion.

"Cheers Everyone" Have a quality day.
 
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