Cold Weather...pour point question

[21Rouge]

Originally Posted By: Ben99GT
Originally Posted By: 21Rouge
Take a look at Redline 0W30. Is there any oil that possesses a lower advertised PP than it i.e. a sexy -76 F BUT digging a bit deeper you find that its MRV is an 'ordinary' 28,000cP
(@-40°C).


Just curious, where did you get this spec?


I wanted to compare the specs of M1 0W30 AFE and the RL 0W30 but was bugged that Mobil posted only the MRV and Redline only the CCS.

I knew it was much more likely that I would get additional info re PDS #s from Redline as compared to XOM and as expected Dave replied to my email inquiry with the MRV # for their 0W30.

 

[CATERHAM]

Originally Posted By: Ben99GT
Originally Posted By: 21Rouge
Originally Posted By: Samilcar
Pennzoil Yellow bottle conventional on the left hand side, Pennzoil Platinum on the right hand side.


-39 Pour point -39

5,800(-30) CCS(cP) 5,150(-35)

15,900(-35) MRV(cP) 14,800(-35)


Even though the pour points are the same, the MRV number is 7% thinner at the same -35°C. CCS is 12% thinner even though the tested temperature for Platinum is 5° colder than the yellow bottle measurement.


And that is how to compare oils re their cold weather abilities i.e. PP is of minimal importance.


It's important if the temperature -40°C and you are using Platinum.

Not really.
The fact that the oil will pour at -39C doesn't mean the engine will crank or the oil will pump; that's why the pour point is a misleading spec'.

 

[shpankey]

I would love to see that comparison too.

 

[Ben99GT]

Originally Posted By: CATERHAM
Originally Posted By: Ben99GT
Originally Posted By: 21Rouge
Originally Posted By: Samilcar
Pennzoil Yellow bottle conventional on the left hand side, Pennzoil Platinum on the right hand side.


-39 Pour point -39

5,800(-30) CCS(cP) 5,150(-35)

15,900(-35) MRV(cP) 14,800(-35)


Even though the pour points are the same, the MRV number is 7% thinner at the same -35°C. CCS is 12% thinner even though the tested temperature for Platinum is 5° colder than the yellow bottle measurement.


And that is how to compare oils re their cold weather abilities i.e. PP is of minimal importance.


It's important if the temperature -40°C and you are using Platinum.

Not really.
The fact that the oil will pour at -39C doesn't mean the engine will crank or the oil will pump; that's why the pour point is a misleading spec'.


The pour point figure is a good estimation of the temperature at which an oil is readily pumpable.

 

[addyguy]

Nope, the MRV temperature is the temperature at which oil is readily pumpable.

The 'pour point' is a misleading term - it should be called the 'movement point'. Pour point is 5 degress above the temp at which the oil completely stops moving, so even at the pour point, the oil is just barely moving.

You have threee temps (eg for a 5w30):

Cranking temp - tested at -30C, oil can be 'cranked through' realativley easily.

Pumping temp - tested at -35C, oil can be pumped realtively easily with some force.

pour point - for most 5w30 dinos, around -36-42C, the temp at which the oil just barely moves.....

 

[Ben99GT]

Originally Posted By: addyguy
Nope, the MRV temperature is the temperature at which oil is readily pumpable.


Pour point tells you the temperature at which oil will stop pouring/flowing under its own weight. Engines apply pressure to the oil and will pump oil below its pour point, but how will it return to pan if it can't flow under it's own weight? MRV and CCS better simulate conditions that are seen in the engine as they apply shear, but pour point is not irrelevant.

Quote:
The 'pour point' is a misleading term


I find it to be a pretty apt term.

 

[mikiee]

That video was pretty dramatic. I always thought that oil still flowed like normal up to it's pour point. Even the syn in the video was like molasses at pour point. I'd like to see a video of dino vs. syn at 0 or 10 degrees. That would be more real world like for most of us. (the video had a syn blend, not full dino)

 

[CATERHAM]

Originally Posted By: mikiee
That video was pretty dramatic. I always thought that oil still flowed like normal up to it's pour point. Even the syn in the video was like molasses at pour point.

And that demonstration was at -40 degrees, the actual PP of M1 5w30 is at -45C, the point as addguy summarized so well, the oil barely moves; forget will actually flow or lubricate.