variations in reported pour points of a motor oil

[Virtus_Probi]

It's hard enough to find CCS and MRV data for the temps from the SAE spec, much less a bunch of random temperatures.
The PQIA only publishes CCS at the temp appropriate for the "W", believe maybe the ROC had MRV for some oils but am not sure without looking (which I only do sparingly with that website). Mobil only gives pour points for most of their oils that I am interested in, but I do see MRV results for a few (M1 0W40 and 0W30 AFE, for example).

 

[OVERKILL]

Originally Posted By: merconvvv
Why should i have to "guess" at mrv ccs values?

I am not making any "accusations".

Tests results can be provided as pass/fail or numerical scores can be given instead.

So what is the mrv ccs of both oils at -40c ?

If you dont know just say so !


I think you are having a hard time with the concept here. The limits for CCS and MRV (which have a 5 degree split between them, CCS is always 5C higher than MRV) were established based on values that were deemed to be appropriate limits before:

1. The cranking speed of the engine was impacted (CCS)
2. The oil was unable to be pumped (MRV)

Ergo, there is absolutely no reason for an oil to be tested once it no longer falls within those limits. The lowest W rating the oil meets based on its performance in those two metrics determines what you see on the bottle. So a 10w-xx for example did not meet the CCS and MRV requirements for the 5w-xx designation, it failed one or both of the tests. Subsequently, the MRV and CCS data you see published (if provided) are for the best cold temperature rating the product was able to achieve.

Not all oil companies provide the CCS and MRV performance data for all of their products. Mobil doesn't provide it for M1 5w30 and 10w30 for example, but do for other grades.

Now, Shell DOES provide us with a TDS for their 10w30 and 5w30 synthetic products, here is their Pennzoil Ultra Platinum 10w30 for example.

CCS @ -25C is 4,100cP
MRV @ -30C is 8,700cP

The limits for the product to achieve the 5w-xx designation are, as per J300, 6,600cP for CCS @ -30C and 60,000cP for MRV at -35C. Using the "doubling" rule we can immediately see that it is going to fail CCS well before it fails MRV. The pour point for this product is listed as -45C BTW. So, if tested using the 5w-xx temperatures, we'd have (roughly):

CCS @ -30C is 8,200cP (FAIL)
MRV @ -35C is 17,400cP (Pass)

You could extrapolate down further, but since CCS has already failed, the product would not be tested for those temperatures.

Now, let's do the same exercise for their conventional product, PYB 10w30:
CCS @ -25C is 6,170cP
MRV @ -30C is 15,400cP

Doubled, we end up with:
CCS @ -30C is 12,340cP (FAIL)
MRV @ -35C is 30,800cP (Pass)

HOWEVER, the pour point for this product is -30C. Which means that the MRV above is likely wrong and the oil has already hit its gel point well before it gets to -35C.

 

[kschachn]

Originally Posted By: merconvvv
Why should i have to "guess" at mrv ccs values?
I am not making any "accusations".
Tests results can be provided as pass/fail or numerical scores can be given instead.
So what is the mrv ccs of both oils at -40c ?
If you dont know just say so !

No, I don't know and neither does anyone else on this board unless they have some sort of insider knowledge. Besides, it is data from a test being run outside of the prescribed parameters. Why would such a number be published? It would be as relevant as publishing a result at -99F or 300F.

And as to an accusation, you keep saying that something is missing but never give details about exactly what is missing:

Quote:
The standard for w rating does not provide a complete picture.

What, exactly is incomplete?

 

[merconvvv]

I dont agree with your definition of random numbers !

A plot or table of say mrv or ccs v. temp starting near the pour point is not asking for a bunch of random numbers. I am sure someone in industry or acedemia has done this.

 

[merconvvv]

Overkill i think you are posting what i am thinking.

It is possible that m1 10w30 fails to meet the 5w rating by a hairline (almost made the 5w) but could be superior in every other way.

 

[kschachn]

Hopefully you are defining "superior" as minutely as you wish to define the cold weather performance. But if that is your goal then why not buy M1 0W-40? With that oil you have clearly demonstrated superior performance as well as proven superior cold weather pumpability over either M1 5w30 or 10w30.

 

[merconvvv]

Because my ford burns 1 quart of m1 0w40 every 700 miles on highway !

 

[kschachn]

Originally Posted By: merconvvv
Because my ford burns 1 quart of m1 0w40 every 700 miles on highway !


Well perhaps try Castrol 0W-40 as it has even more demonstrated superior performance than even M1 0W-40. The consumption may also be lower.

So where in Illinois do you live? North, central or southern? What cold weather performance standard (W rating) is needed for your location?

 

[merconvvv]

Chicago area. Both winter cars (not rx7

are specd for 5w according to owner manuals. Though i used to have an 86 rx7 that was all season with sand bags in rear for ice and snow. She wore blizzaks.

 

[Garak]

Originally Posted By: merconvvv
A plot or table of say mrv or ccs v. temp starting near the pour point is not asking for a bunch of random numbers. I am sure someone in industry or acedemia has done this.

Most of the matter has already been addressed in the thread, and I think more or less to your satisfaction, but there are still a couple points. I don't know if academia would bother. I'm sure someone has gotten a relationship somewhere as to what an MRV or CCS curve would look like when dropping below the appropriate temperatures for the oil's pumpability. But, having a bunch of specific and current examples, no way. I don't think anyone in the industry would be terribly interested what results show when one runs M1 10w30, specifically, in such tests at 20 degrees colder than specified, or a 20w-50 at -60 C. Competitors have some incentive to keep each other honest, but if Shell, for example, is happy that M1 10w30 is an actual 10w-XX example and not a 5w-XX ringer, I'm not sure they want to test further than that for their own edification.

And, if you're Expedition is burning one quart of M1 0w-40 every 700 highway miles (I've seen worse), the first thing I'd do is ditch the synthetic.

 

[merconvvv]

If none one in oil industry or academia has ever thought of a plot of mrv or ccs v temp then that would explain the inadequate SAE "W" standard.
Garak please i never said test 20w50 at -60.
Please note from your cut and pasted i said plot of mrv ccs v temp starting from near the pour point.
I ditched 0W => burning a quart per 700 hwy miles
I ditched 5W => burning a quart per 700 hwy miles
I did not ditch synthetic.
I adopted high quality synthetic 10W30=>burning one sixth of quart per 700 hwy miles.

Quaker state advance durability 5W30
Pour point -33c
Ccs at -30 5840
Mrv at -35 21900

M1 10w30 pour point -42c
No other info given !

Which will provide better winter protection and by how much?

I will stick with a high quality 10W30 synthetic.

Testing and standards seem to be controlled by industry anyway so that is for another rainy day.

 

[merconvvv]

"If no one" edit up there.

 

[Shannow]

Originally Posted By: merconvvv
If none one in oil industry or academia has ever thought of a plot of mrv or ccs v temp then that would explain the inadequate SAE "W" standard.


Inadequate in what way ?

Need oil to run at -X, then it needs an MRV no greater than y, and a CCS no greater than z.

If it meets the next temperature range down, then it get labelled as such.

What's inadequate about that ?

Of course academia has such curves...just google MRV and CCS versus temperature and read your heart out.

The fact that no-one bothers to test certified oils at every other temperature doesn't make J300 flawed...

But to re-iterate, as you've obviously got some point to make that you aren't quite making...

Inadequate in what way ?

 

[Shannow]

Originally Posted By: merconvvv

Quaker state advance durability 5W30
Pour point -33c
Ccs at -30 5840
Mrv at -35 21900

M1 10w30 pour point -42c
No other info given !

Which will provide better winter protection and by how much?


If you need to start at -35C, then the 5W30 is your oil...if the 10W30 met the same MRV and CCS...then IT WOULD BE LABELLED 5W30...

 

[merconvvv]

Shannon suppose i had taken 20 identical cars 10 years ago and divided them into 2 groups with identical driving in chicago during winter months only say november to march as we are talking about winter protection. After 10 years which group would show more engine wear and how significant?
Group a
Quaker state advance durability 5W30
Pour point -33c
Ccs at -30 5840
Mrv at -35 21900

Group b
M1 10w30 pour point -42c
No other info given !

 

[Shannow]

As I've gone over previously...

"W" USED to be partly based on pour point...and they found that it DIDN'T WORK !!!

So they adopted CCS and MRV.

If your Mobil 1 is rated 10W, then you are guaranteed that it didn't pass 5W, as if it did, it would be labelled 5W.

Thus the 5W is your best go to in weather requiring a 5W, regardless of what Mobil's pour point is...

what's the problem with that ?

Where is the flaw in J300 ?

 

[merconvvv]

Shannon did you say group a with qsad 5w30 or group b with mobil 1 10w30? The fact that you dont know how close m1 10w30 is to being a 5w30 is one big flaw. It would have been better to rate oils ...5w 6w 7w 8w 9w 10w ...atleast reporting mrv ccs values obtained while testing should not be forbidden. Oil formulations can be a secret ofcourse.
Mobil 1 10w30 could be a 6w etc which can only help the consumer in making informed decisions.

 

[kschachn]

Originally Posted By: merconvvv
Shannon did you say group a with qsad 5w30 or group b with mobil 1 10w30? The fact that you dont know how close m1 10w30 is to being a 5w30 is one big flaw. It would have been better to rate oils ...5w 6w 7w 8w 9w 10w ...atleast reporting mrv ccs values obtained while testing should not be forbidden. Oil formulations can be a secret ofcourse.
Mobil 1 10w30 could be a 6w etc which can only help the consumer in making informed decisions.

What a jumble of nonsense.

 

[merconvvv]

Kschachn when one is ignorant they resort to comments such as yours.

 

[merconvvv]

Remember your comment if you ever state m1 0w40 is a light weight 40