Seems like a no brainer to run 0-x rather then 5-x for cold temps?

[jalikaria24]

Here in Alberta we get down to -30 and -40 sometimes and the temp will judt stay there. Most vehicles seem to be specd for 5w-x
I was curious on if it’s a no brainer just to run 0w-x for the vehicles for winter. Seems like a little better cold flow shouldn’t do any harm. Or would you only stay at 5w-20 if the car is specd for 5w 20

as far as I read and unless im wrong, ir seems like running a lower first number just helps for cold flow and the main number that matters is the number After which is operating temp.

the car in question is a Mazda 2.3L

 

[Snagglefoot]

Some manufacturers are asking for 0wX below -20 F (-29 C) and some have been making that recommendation for the past 20 years ; GM for one. I have 0w30 in my truck and 0w20 in my car. I’m in SE BC ( not the lower mainland). I find -30 C does occur and -20 C is common. The truck has to make a start every weekday afternoon after cold soaking for 9 hours. No plug-ins available at work.

 

[kschachn]

Along with your question about high mileage oils, this is also one of the top five most asked questions. It's also not about "flow", except for the flow in the immediate vicinity of the oil pickup tube. It's about cranking and pumpability.

There is no technical reason not to run a 0W rated oil of the appropriate operating viscosity.

 

[Tman220]

0wXX is definitely a good thing in temps below zero. It's only going to get oil flowing quicker to the moving parts when you perform the worst task possible for any engine, cold starting.

I dont care if an engine calls for 10w30, 0W30 would still be better for cold winters.

 

[kschachn]

0wXX is definitely a good thing in temps below zero. It's only going to get oil flowing quicker to the moving parts when you perform the worst task possible for any engine, cold starting.

I dont care if an engine calls for 10w30, 0W30 would still be better for cold winters.

A 5W rated oil will have adequate "flow" as will a 0W rated oil at well below zero, up until approximately -35F. And it's not about flow when the engine starts it's about film thickness, and any oil will be well thick enough at those temperatures.

 

[madeej11]

0w30 would probably be beneficial starting at about negative 20-25 degrees fahrenheit.-20 farenheit is around-28 celcius.

 

[285south]

True for cold regions.

For instance in the southwest, I just changed my neighbors oil from GC that I changed last year (to clean the motor from them using conventional) to this past weekend with Castrol Titanium EP (gold) three bottles of 10w30 and two 5w30, for our winter which will get to a cold 36*F in January and currently in the morning 51*F

 

[2EHA]

Very surprised somebody living in a literal igloo hasn’t posted about why a block heater is the best thing ever

 

[mahanddeem]

Some 0w30s are thicker than some 5w30s. So when comparing several things have to be taken into consideration. 0w30 is not a "colder version" of 5w30.

 

[Passport1]

Years ago I had a VW Rabbit diesel. The lowest viscosity we had then was 10W-30 conventional. The block heater made a huge difference getting the bunny started at below zero. Of course when the #2 diesel turned to jello my efforts were macht nichts.

 

[The Critic]

There is no technical reason not to run a 0W rated oil of the appropriate operating viscosity.

For many years, GM specified 5W-30 for their engines but only permitted the usage of 0W-30 under certain temperature conditions.
Theoretically, a grade with a narrow viscosity span will use fewer VII's and be more stable. While VII's have improved, fundamentally, a 5W-30 should still be more shear stable than a 0W-30.

Of course, we are talking about API/ILSAC approved GF-5+/GF-6 oils here.

 

[tcp71]

The pour point can tell you something as well. There are 5wX oils with lower pour points than 0wX oils.

 

[toneydoc]

Put in a 0w20

 

[FordMan59]

I am in an area that occasional sees temps in the negative single digits using10w40 conventional for the past 45 years and don't worry about it. Even had a few days back in Dec. 1989 when the temps dropped into the negative teens and twenties F. I think the lowest it got was -28F with -56F wind chill. She was a little slow turning over but, she started and didn't do any apparent damage. I've used a few engines in access of 200K miles and one in access of 500K. I currently have 2 cars with over 200K. When I quit using the one with 500K miles on it the compression was still 145-155 PSI across the board. I'm pretty sure something else is going to take the car out of service before a handful of days at negative teens over a 15-20 year period.

 

[edyvw]

Very surprised somebody living in a literal igloo hasn’t posted about why a block heater is the best thing ever

Block heater rules in cold. I even have it in my SIenna here in CO, as warming up 2GR-FE at 32 degrees or below is seriously daunting task, regardless of insulated garage.

 

[edyvw]

I am in an area that occasional sees temps in the negative single digits using10w40 conventional for the past 45 years and don't worry about it. Even had a few days back in Dec. 1989 when the temps dropped into the negative teens and twenties F. I think the lowest it got was -28F with -56F wind chill. She was a little slow turning over but, she started and didn't do any apparent damage. I've used a few engines in access of 200K miles and one in access of 500K. I currently have 2 cars with over 200K. When I quit using the one with 500K miles on it the compression was still 145-155 PSI across the board. I'm pretty sure something else is going to take the car out of service before a handful of days at negative teens over a 15-20 year period.

I started once Opel Vectra B in Bosnia at -42, having 10W40 in it. It si OK I guess occasionally, but all the time? It will take toll.

 

[Shel_B]

[...] I just changed my neighbors oil from GC that I changed last year (to clean the motor from them using conventional) to this past weekend with Castrol Titanium EP (gold) three bottles of 10w30 and two 5w30, for our winter which will get to a cold 36*F in January and currently in the morning 51*F

Why not just 5W-30? What benefit to you believe you derive from mixing those two weights?

 

[kschachn]

The pour point can tell you something as well. There are 5wX oils with lower pour points than 0wX oils.

Which on the other hand also illustrates that pour point is not always an accurate indicator of cold weather performance. This is where the problem came in and why SAE J300 was rewritten.

 

[SteveG4]

Which on the other hand also illustrates that pour point is not always an accurate indicator of cold weather performance. This is where the problem came in and why SAE J300 was rewritten.

Anymore, I'm looking at the Cold Cranking Simulator numbers at (°C), cP, relating to ASTM D5293.

 

[Kuato]

Here in Alberta we get down to -30 and -40 sometimes and the temp will judt stay there. Most vehicles seem to be specd for 5w-x
I was curious on if it’s a no brainer just to run 0w-x for the vehicles for winter. Seems like a little better cold flow shouldn’t do any harm. Or would you only stay at 5w-20 if the car is specd for 5w 20

as far as I read and unless im wrong, ir seems like running a lower first number just helps for cold flow and the main number that matters is the number After which is operating temp.

the car in question is a Mazda 2.3L

You're spot on. At those temperatures, 0w-xx is your oil. And last number, as you said, is at operating temp.