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

[Srt20]

Wisconsin winters. Truck mainly sits outside.
2018 F150 3.5L Ecoboost. I am considering using 0w-40 Castrol Edge in this truck because of the shearing and fuel dilution in UOA's I see on here. Do you guys feel 0w-40 is fine for WI winters where the temp can reach -30*F? Thanks

 

[StevieC]

It won't be a catastrophic thing but I would rather use something a little thinner in super cold temperatures. You could do a UOA and see how it affects your wear metals being that thick in the cold. Would also show you fuel dilutions as well to see if they really are something to be concerned with in your application. You might not have the problem like others or as bad as others.

 

[PimTac]

What is your driving routine? Short trips lead to fuel dilution. How many miles do you plan on driving annually?

A 0w30 would be dandy for that motor.

 

[OVERKILL]

The 0w-40 would offer better cold temperature performance, not worse. Whether it is overkill, probably not. I run 0w-40 year round as that's what's spec'd, I can't see it being a problem for you.

 

[JHZR2]

Have you done a UOA to verify your driving routine causes the issues you mention?

What is the lowest ambient temperature you encounter in the winter (not wind chill).

 

[BrianF]

if the 0w40 is the best for the fuel/shearing then run that all year. -30F is cold but either oil will be just fine for that. Don't waste your time/money and oil for these seasonal oil changes. I run 5w30 all year in my Tb and it gets cold up here and it has yet to blow up.

Run what works best for your engine set up and when it gets real cold just plug it in a few hours before start up. On BITOG most overthink cold starts and think you need 5 and 0w oils for those cold Florida start ups. Some guys up here run 15w40 conventional oil in their diesels all year, they just plug in before starting.

 

[Srt20]

Originally Posted By: PimTac
What is your driving routine? Short trips lead to fuel dilution. How many miles do you plan on driving annually?

A 0w30 would be dandy for that motor.


My driving route will be generally short trips, 5-10 city miles, with occasional long trips, 300-3000 miles. Probably at least a 300 mile trip once or so a month. I would guesstimate it will get 15,000ish miles per year.

 

[madeej11]

Just a thought but what about getting that 40 weight up to operating temps? Maybe use the 5w30 or 0w30 and do more frequent OCI's.

 

[Srt20]

Originally Posted By: JHZR2
Have you done a UOA to verify your driving routine causes the issues you mention?

What is the lowest ambient temperature you encounter in the winter (not wind chill).


I have not done a UOA yet. I ran FF to 3,000 miles, then put 5w-30 Edge. Its now at 8,000 miles, and due for an oil change. I was figuring on waiting for a UOA after the next OCI to clear out any break in materials.

Coldest ambient at start up could be -30*F, though it may see colder when on a west trip and passing through North Dakota at night. Though it would be running and fully warmed. When we leave home, we drive straight through.

 

[Srt20]

Originally Posted By: madeej11
Just a thought but what about getting that 40 weight up to operating temps? Maybe use the 5w30 or 0w30 and do more frequent OCI's.


Thats a thought also. I guess I should mention, that most of the short trips I do are taking the kids to school. If its -30*F, the school will cancel anyway...

 

[Srt20]

I will also add, if its below 0*F, I hit the remote start anyway and let it run for 10 mins before leaving.

 

[BrocLuno]

Originally Posted By: StevieC
It won't be a catastrophic thing but I would rather use something a little thinner in super cold temperatures. You could do a UOA and see how it affects your wear metals being that thick in the cold. Would also show you fuel dilutions as well to see if they really are something to be concerned with in your application. You might not have the problem like others or as bad as others.


What's thinner than 0W ??

 

[Srt20]

Originally Posted By: BrocLuno
Originally Posted By: StevieC
It won't be a catastrophic thing but I would rather use something a little thinner in super cold temperatures. You could do a UOA and see how it affects your wear metals being that thick in the cold. Would also show you fuel dilutions as well to see if they really are something to be concerned with in your application. You might not have the problem like others or as bad as others.


What's thinner than 0W ??


I maybe wrong, but is 5w-30 not thinner than 0w-40? Maybe Ive been understanding it wrong all this time?

 

[OVERKILL]

Originally Posted By: Srt20
Originally Posted By: BrocLuno
Originally Posted By: StevieC
It won't be a catastrophic thing but I would rather use something a little thinner in super cold temperatures. You could do a UOA and see how it affects your wear metals being that thick in the cold. Would also show you fuel dilutions as well to see if they really are something to be concerned with in your application. You might not have the problem like others or as bad as others.


What's thinner than 0W ??


I maybe wrong, but is 5w-30 not thinner than 0w-40? Maybe Ive been understanding it wrong all this time?


The number in front of the W is the "Winter" rating for the oil. a 0W-xx offers better winter performance than a 5W-xx at the extreme end of the temperature range. So, while the 5w-30 is thinner at operating temperature, as one approaches the CCS/MRV temperatures there's a crossover where the 0w-40 will thicken less than the 5w-30.

 

[Srt20]

Originally Posted By: OVERKILL
Originally Posted By: Srt20
Originally Posted By: BrocLuno
Originally Posted By: StevieC
It won't be a catastrophic thing but I would rather use something a little thinner in super cold temperatures. You could do a UOA and see how it affects your wear metals being that thick in the cold. Would also show you fuel dilutions as well to see if they really are something to be concerned with in your application. You might not have the problem like others or as bad as others.


What's thinner than 0W ??


I maybe wrong, but is 5w-30 not thinner than 0w-40? Maybe Ive been understanding it wrong all this time?


The number in front of the W is the "Winter" rating for the oil. a 0W-xx offers better winter performance than a 5W-xx at the extreme end of the temperature range. So, while the 5w-30 is thinner at operating temperature, as one approaches the CCS/MRV temperatures there's a crossover where the 0w-40 will thicken less than the 5w-30.


Interesting. Is there a place I can look it up to find out where that crossover point is?

 

[tcp71]

I run castrol 0w40 in my 2016 F150 eco. Summer while towing 7500lb trailer and winter when it's -35C outside. Stock up when it's on sale and use it year round. It's a light 40wt anyway. Shear and dilution can put it in grade rather quickly.

 

[OVERKILL]

Originally Posted By: Srt20


Interesting. Is there a place I can look it up to find out where that crossover point is?


It isn't universal. You can figure out roughly where it might be by going up/down via CCS and MRV.

CCS and MRV both roughly half/double per 5C degree change in temperature, so, let's say you had two oils with the following specs:

Castrol 0w-40:
CCS @ -35C: 6,200cP

Castrol 5w-30:
CCS @ -30C: 5,800cP


At -30C, the 0w-40 would be around 3,100cP. Conversely, at -35C, the 5w-30, assuming it didn't gel, would be 11,600cP.

This rule starts to break down once you get up close to 0 and at some point, the 0w-40 is going to start being thicker. You can use these numbers, in conjunction with the 40C visc to figure out where that crossover point might reside.

 

[kschachn]

Originally Posted By: Srt20
Originally Posted By: madeej11
Just a thought but what about getting that 40 weight up to operating temps? Maybe use the 5w30 or 0w30 and do more frequent OCI's.

Thats a thought also. I guess I should mention, that most of the short trips I do are taking the kids to school. If its -30*F, the school will cancel anyway...

The 0W-40 will warm up faster than the 5W-30.

 

[kschachn]

Originally Posted By: Srt20
Wisconsin winters. Truck mainly sits outside.
2018 F150 3.5L Ecoboost. I am considering using 0w-40 Castrol Edge in this truck because of the shearing and fuel dilution in UOA's I see on here. Do you guys feel 0w-40 is fine for WI winters where the temp can reach -30*F? Thanks

I used Castrol 0W-40 in my old BMW when it sat outside in northern Wisconsin, when you get down that low that's when the 0W rating starts coming into play over the 5W. Like Overkill has outlined it will be thinner at extremely low temperatures and that's a good thing.

At those temperatures you're not going to do any better than an oil with a 0W rating.

 

[StevieC]

Originally Posted By: OVERKILL

It isn't universal. You can figure out roughly where it might be by going up/down via CCS and MRV.

CCS and MRV both roughly half/double per 5C degree change in temperature, so, let's say you had two oils with the following specs:

Castrol 0w-40:
CCS @ -35C: 6,200cP

Castrol 5w-30:
CCS @ -30C: 5,800cP


At -30C, the 0w-40 would be around 3,100cP. Conversely, at -35C, the 5w-30, assuming it didn't gel, would be 11,600cP.

This rule starts to break down once you get up close to 0 and at some point, the 0w-40 is going to start being thicker. You can use these numbers, in conjunction with the 40C visc to figure out where that crossover point might reside.


This I didn't know.