[Mountain]

Originally Posted by TrackClub

Wont disagree that 0w40 is a better option for all 4 season driving and especially in winter. And no doubt thats why GM picked it as it is the most versatile. But for summer only car it really has no advantage over 5w40.

I'll challenge this: Why is that?

[TrackClub]

Originally Posted by Mountain

I'll challenge this: Why is that?

Because the number proceeding the W (which stands for "winter") is representative of oil viscosity at minus 18C (0F) while the second number following the W is representative of oil viscosity at plus 100C and is completely unrelated to the first number. Hence the name "multi grade oil". Hence a 5w40 oil will provide the same necessary viscosity protection at operating temps as 0W40.

And since we dont get cold temps in summer time where i live there is no specific reason to use oil which provides max cold start capabilities such as 0W. Having said that many manufacturers use them as they provide best cold start protection (obviously and specifically in winter).

NB some experts will argue that using too low a winter start grade in hot climates may actually be counter productive (to proper protection at a start time).

[Boost Creep]

Originally Posted by TrackClub

Because the number proceeding the W (which stands for "winter") is representative of oil viscosity at minus 18C (0F) while the second number following the W is representative of oil viscosity at plus 100C and is completely unrelated to the first number. Hence the name "multi grade oil". Hence a 5w40 oil will provide the same necessary viscosity protection at operating temps as 0W40.

And since we dont get cold temps in summer time where i live there is no specific reason to use oil which provides max cold start capabilities such as 0W. Having said that many manufacturers use them as they provide best cold start protection (obviously and specifically in winter).

NB some experts will argue that using too low a winter start grade in hot climates may actually be counter productive (to proper protection at a start time).

+1
I wouldn't want to use a 0w oil unless I had to, or it was required.

I would prefer to use a 5w40 if I could versus the 0w40 they are offering us.

Important ingredients in oil are phosphorus and zinc, both wear reducing elements. Both have been reduced in our oil to protect cat converter warranties.

Here a good Mobil 1 chart that gives you Zinc and Phosphorus ppm's.

https://mobiloil.com/~/media/amer/us...pecs-guide.pdf

The 0w40 they are offering is better than the 5w30 as far as additives, but not the best we could be using.
I used the Turbo Diesel 5w40 in my previous LS3 and LS2 engines and both were much quieter than before, less sewing machine noise, and both had better oil pressure when hot.

As you can see on the chart the European and TD oils have more anti wear additives than most of the others.

[TrackClub]

Good chart and ya emissions do play a big role here.
Interesting i couldnt find 5w40 esp formula m oil as our manual lists it as one of the non dexos 2 certifed oils approved by GM. It would be good to see what properties it has. For me it is Valvoline as it is easily obtained. But it is also good to hear GM has finally decided to offer oil which isnt DD duty only. I guess those 2 free oil changes will actually be good for something

[jreagle56]

I'm just not feeling a 0w oil for my engine. seems like with some fuel dilution and shearing of the VII's, the 40 will thin out toward the 0 weight pretty fast; not lasting as a 40 for a full OCI...... just my opinion anyway.

M1 5w30 ESP has a higher HTHS and less VII to shear down.
Wonder why the engineers didn't consider this one?? Its a EURO oil so maybe the SAPS are too low for USA fuel??

[Mountain]

Originally Posted by TrackClub

Because the number proceeding the W (which stands for "winter") is representative of oil viscosity at minus 18C (0F) while the second number following the W is representative of oil viscosity at plus 100C and is completely unrelated to the first number. Hence the name "multi grade oil". Hence a 5w40 oil will provide the same necessary viscosity protection at operating temps as 0W40.

And since we dont get cold temps in summer time where i live there is no specific reason to use oil which provides max cold start capabilities such as 0W. Having said that many manufacturers use them as they provide best cold start protection (obviously and specifically in winter).

NB some experts will argue that using too low a winter start grade in hot climates may actually be counter productive (to proper protection at a start time).

Take a look at a few 5w-40’s and their kinematic viscosities, viscosity index, ZDDP ppm, and sulfate ppm. Most I've see are as good or worse than 0w-40.

In example, if you look at the Mobil 1 0w-40 (FS in specific, also to the ESP) and compare it to:
Valvoline 5w-40 MST (Dexos 2)
-Kinematic viscosities are nearly the same.
-The VI much lower
-HTHS is nearly the same

Motul 5w-40 8100 (Dexos2)
-Low temperature kinematic viscosity is higher, but high temperature kinematic viscosity is nearly the same
-The VI is lower
-HTHS is the same
-ZDDP is unkown
-Sulfated ash is lower
https://www.motul.com/rs/en/products/8100-x-clean-5w40

Mobil 1 5w-40 Turbo Diesel (non-Dexos 2)
-Low temperature kinematic viscosity is higher, but high temperature kinematic viscosity is nearly the same
-The VI is much lower
-HTHS is nearly the same
-ZDDP is the same/nearly the same
-Sulfated ash is nearly the same
https://mobiloil.com/en/motor-oils/m...o-diesel-truck

I 100% agree with you from a theoretical point of view. When you look at the test qualifications, it leads me otherwise.

Remeber, VI and VII are related... it depends what kind of VIIs are used.

900+ppm ZDDP in a gasoline engine formulated oil is pretty damn good these days. Yes, going to a multi-applicable/diesel oil gets you more elevated ZDDP ppm, but you need to consider a few things: NOVACK and sufated ash; then whether youre going to run a catch-can.

[TrackClub]

Originally Posted by Mountain

Take a look at a few 5w-40’s and their kinematic viscosities, viscosity index, ZDDP ppm, and sulfate ppm. Most I've see are as good or worse than 0w-40.

In example, if you look at the Mobil 1 0w-40 (FS in specific, also to the ESP) and compare it to:
Valvoline 5w-40 MST (Dexos 2)
-Kinematic viscosities are nearly the same.
-The VI much lower
-HTHS is nearly the same

Motul 5w-40 8100 (Dexos2)
-Low temperature kinematic viscosity is higher, but high temperature kinematic viscosity is nearly the same
-The VI is lower
-HTHS is the same
-ZDDP is unkown
-Sulfated ash is lower
https://www.motul.com/rs/en/products/8100-x-clean-5w40

Mobil 1 5w-40 Turbo Diesel (non-Dexos 2)
-Low temperature kinematic viscosity is higher, but high temperature kinematic viscosity is nearly the same
-The VI is much lower
-HTHS is nearly the same
-ZDDP is the same/nearly the same
-Sulfated ash is nearly the same
https://mobiloil.com/en/motor-oils/m...o-diesel-truck

I 100% agree with you from a theoretical point of view. When you look at the test qualifications, it leads me otherwise.

Remeber, VI and VII are related... it depends what kind of VIIs are used.

900+ppm ZDDP in a gasoline engine formulated oil is pretty damn good these days. Yes, going to a multi-applicable/diesel oil gets you more elevated ZDDP ppm, but you need to consider a few things: NOVACK and sufated ash; then whether youre going to run a catch-can.

All good points but frankly i have a 5 yr power train warranty std and thats a bottom line for me. And i wont use anything which isnt speced in the manual the car came with. And for the summer only 5w40 is a good choice imo. Plus easily available. But if GM were to override the manual and mandate Canola id switch in a heartbeat. Because they warranty the motor and everything else for that matter.

On a serious note i dont expect to keep my car beyond 3 yrs and bumper to bumper warranty. Part of my new dd and track dual use strategy as i got older and started to dislike a PITA factor. With my Vette track queen which i used to beat on for some 10 yrs i used mobil 1 5w30 exclusively and motor ran strong and still is under a new owner who continues to track her regularly. Even with some power mods (cam etc) and not even a catch can.

[Mountain]

Originally Posted by jreagle56

I'm just not feeling a 0w oil for my engine. seems like with some fuel dilution and shearing of the VII's, the 40 will thin out toward the 0 weight pretty fast; not lasting as a 40 for a full OCI...... just my opinion anyway.

M1 5w30 ESP has a higher HTHS and less VII to shear down.
Wonder why the engineers didn't consider this one?? Its a EURO oil so maybe the SAPS are too low for USA fuel??

Interesting that the M1 5w-30 ESP isnt a 40. My guess is the HTHS came up just shy; the kinematic viscosity is 40-weight worthy.

The VI and sulfated ash are low. This, along with the HTHS and ZDDP not being that great is probably why.

Anyway, interesting discussion here.