0w-40 all year, or 5w-30 in winter?

[oil_film_movies]

Originally Posted By: OVERKILL
That's really not a lot. Here's another example from Mobil for a 5w30:
Your example is a heavy diesel engine oil. It needs more VM to prop up the HTHS to 3.7. Gas engine grades of 5w30 only need to get to HTHS=3.0, and need less VM to get there if their base stocks are decent, like GTL Group III or have some PAO blended in.

 

[OVERKILL]

Originally Posted By: oil_film_movies
Originally Posted By: OVERKILL
That's really not a lot. Here's another example from Mobil for a 5w30:
Your example is a heavy diesel engine oil. It needs more VM to prop up the HTHS to 3.7. Gas engine grades of 5w30 only need to get to HTHS=3.0, and need less VM to get there if their base stocks are decent, like GTL Group III or have some PAO blended in.


But we both know that they don't use majority PAO in blending those grades

Thusly, the grades shown in the PAO-blending guide are not indicative of how the products we see on the shelf are blended. I'm not saying I don't see your point, but what we have seen is that generally, the 0w-xx oils are blended with better bases than their 5w-xx counterparts, which likely negates the VII argument and subsequently means that the treat rate is probably pretty similar in application.

 

[OVERKILL]

If we look at the current MSDS for Mobil 1 5w-20 it shows 40-50% GTL, no PAO
If we look at the current MSDS for Mobil 1 0w-20 it shows 30-40% PAO, 10-20% GTL

This seems to be somewhat typical, and that's for a company that has ready access to PAO. Ones that don't of course don't use it unless they need to (like Castrol in their 0w-40, but none in their 5w-40 for example).

 

[bbhero]

Not what I have noticed over time.....

Many instances Mobil 1 0w40 and Castrol 0w40 have been in spec viscosity range.

Yes there are circumstances where those have dropped down in grade.

There some used oil analysis that have been lower than 40 grade but fuel percentage was higher than 4%.

 

[kschachn]

Is there any evidence that today's Mobil 1 0W-40 formulation is prone to shear, much less Castrol's 0W-40 product?

How would anyone even know given Blackstone's inability to distinguish between mechanical shear and fuel-related viscosity loss? Nearly every UOA on this board is from Blackstone and anything they report in regards to viscosity and flash point has proven to be suspect.

Shear Worry is somehow something that I just have a hard time engaging. SonofJoe has repeatedly stated that today's VII are stable and not susceptible to mechanical shear, at least not to the extent that they were years ago. Besides wouldn't it highly application dependent?

 

[BrocLuno]

AFAIK all the 0W oils are less intensely treated with VII's. They all start with better base stocks

 

[StevieC]

Originally Posted By: BrocLuno
AFAIK all the 0W oils are less intensely treated with VII's. They all start with better base stocks

That was my understanding but the 0w40 might be a little different because there is such a spread from 0 to 40.

 

[BrocLuno]

Maybe, but I still think they are the cream of the crop. I'd just run the 0W-40 year round be happy

 

[OVERKILL]

Originally Posted By: BrocLuno
Maybe, but I still think they are the cream of the crop. I'd just run the 0W-40 year round be happy

 

[jongies3]

Run it, I've ran GC in some cold Montana winters without any ill effects, decided to go back to 0w30 though for slightly better pumpability.

 

[147_Grain]

0W-30 in the winter and 0W-40 in the summer.

Shorter OCI with the fuel dilution.

 

[NO2]

Use 0w30 all of the time and change the oil according to the maintenance monitor, or be a little more aggressive with the OCI. Don't extended it. Going to a 0w-40 is not going to change the fact that some of your oil is displaced by fuel and will not lubricate properly.

A high quality synthetic like Mobil 1 Advanced Fuel Economy 0w30 has a pour point of -50C, and will flow reasonably well at -30F.

 

[madeej11]

Fuel dilution obviously a factor in Wisconsin winter. Don't know how suceptible 0w40 is to dilution with possibly more VII's than a solid 5w30. Year round in Wisconsin give me something like AMSOIL Signature Series 5w30 any day.Not fact, just an opinion.Great pour point too.

 

[oil_film_movies]

Originally Posted By: NO2
Use 0w30 all of the time and change the oil according to the maintenance monitor, or be a little more aggressive with the OCI. Don't extended it. Going to a 0w-40 is not going to change the fact that some of your oil is displaced by fuel and will not lubricate properly.
Viscosity of a 0w40 will allow a little fuel to be mixed in and still support the film thickness recommended by Ford. About "extending" the OCI, it could be the fuel will increase oxidation rates, so agreeing 6 months or so might be it, if fuel dilution is present above 3% or so.

Originally Posted By: madeej11
Fuel dilution obviously a factor in Wisconsin winter. Don't know how suceptible 0w40 is to dilution with possibly more VII's than a solid 5w30. Year round in Wisconsin give me something like AMSOIL Signature Series 5w30 any day.Not fact, just an opinion.Great pour point too.
The VII's in a 0w40 (vs. 5w30) raise hot viscosity, and fuel lowers it, so we hope the net result at the mid to late stages of an OCI, is an HTHS no less than 3.0. Thats the game, and why using a 0w40 is a good idea since it starts with a higher HTHS.

 

[joekingcorvette]

I would use a 0W-30. The last couple Ford F-150's that I have had recommended a 0W-20 or a 5W-20. What does the owners manual recommend? I use 0W-20 full synthetic in my 5.0 2014 Ford F-150 and it work fine. I thought I seen it in the Mobil 1 website where you can run 0W in anything that requires a higher number. The zero just means it flows better when it's 40 below wind chill like we have in South Dakota. I always buy the 0W if I can find it and that is what is recommended for my Honda Civic. 0W-20...it says it right on the fill cap. I would go by the owners manual and use a full synthetic.

 

[Srt20]

Owners manual calls for 5w30. I am considering 0w-40 because of shear, dillution, and potential issues with timing chains and cam phazers.

I will probably do 6k-7.5k OCI's.

I'm going to do Castrol EDGE 0w-40 next week, and see how it goes.

 

[Olas]

How hot are your summers, and how cold are your winters?

Ambient temps dictate viscosity.

 

[Srt20]

Originally Posted By: Olas
How hot are your summers, and how cold are your winters?

Ambient temps dictate viscosity.


Possible -30*F winter, might hit 100*F summer.

Im not worried about summer, the oil temp onced fully up to operating temp will be warmer than any ambient temp I will ever encounter.

 

[Triple_Se7en]

Originally Posted By: Olas
How hot are your summers, and how cold are your winters?

Ambient temps dictate viscosity.


Hard winters...Yes!
Hot Summers... No!

 

[StevieC]

The cold flow in this video shows it well. (Flowing in the cold, not the rest of the video)

https://youtu.be/VdZ9vCXh_50?t=135