How much does Point Point matter in normal Temps?

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6,987
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Michigan
I guess my question is in normal cold temps like between 0-32 degrees would a 0 or 5w oil flow that much better than a 10w oil?
 
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25,044
Location
ON, Canada eh?
Look at the CST numbers. Some 10w are almost the same as a 5w oil at 40 degrees so I would imagine they would be pretty similar below freezing as well. Not all oils though...
 
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1,339
Location
USA
Believe it or not 5W-20 starts quicker than 0W-30. Noticeably so too. The actual weight of the oil seems to have at least as much to do with cold starts as the winter number.
 
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34,956
Location
NY
You can have two 10W30 oils with different pour points. You can have a 5W20 with a better pour point than a 0W20, same goes for other grades as well. In extreme cold climates it is a good idea to look at the pour points. oilyriser mentions the differences can show up in short hop mpgs, I agree,
 
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1,339
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USA
 Originally Posted By: demarpaint
You can have two 10W30 oils with different pour points. You can have a 5W20 with a better pour point than a 0W20, same goes for other grades as well. In extreme cold climates it is a good idea to look at the pour points.
I agree with you. However, the weight of the oil is a factor. Let me give you this example. My car with German Castrol(pour point -54 C) 0W-30 wouldn't start as quick as when it had Motorcraft 5W-20 in it, which only has a pour point in the -30's I believe. Perhaps that is pumpability or flow rate? I'm not sure what you call it. Somehow an oil can pour at a lower temperature and still not flow as well as something with a less impressive pour point. Pretty wild.
 
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34,956
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NY
\:\! Yes I read that, and buried in my mind is the reason why. My problem is it's buried pretty deep. Hopefully a resident expert can weigh in and dig it up for me.
 
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39,806
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Pottstown, PA
The lighter oil will perhaps get to full flow sooner. It will always take less energy to pump at sensible flow rates. I'll say this poorly ..but .. The way an oil reacts at those cold spec's doesn't have any relationship to its sensible visc. Don't confuse that with meaning that they'll all reach some sensible flow rate in any equivalent manner ..that your oil pump will not be in varied levels of relief between two unlike viscs. Assuming that one is indeed in -35 or -40 conditions, I will assure you that when comparing 0w-40 to 0w-20 ..that you will realize FULL FLOW much sooner with a 0w-20. You will always consume less energy with the lighter oil at any point in the whole process between the two oils in comparison. It will always be easier to pump (assuming like cold spec's). This is PZ PP 0w-20/5w-20/5w-30 MRV viscosity, cP (°C) ASTD D-4684 17,500 (-40) 9,700 (-35) 14,800 (-35) The 0w-20 is higher than the 5w-30 ..but -5f colder. When comparing the 5w-20 to the 5w-30 ..the comparison is more clear. Shell 0w-40 has an MRV of 24182Cp @ -40 All of them won't exceed stress limits for their respective designations at the designated temps (CCS). Here's the CCS spec's for the same 20 grade oils CCS Viscosity, cP (°C ) ASTM D-5293 4840 (-35) 4,250 (-35) 5,150 (-35) 4,570 (-30) Here's 5w-50 CCS Viscosity, cP (°C ) ASTM D-5293 4980 (-30) MRV viscosity, cP (°C) ASTD D-4684 24,000 (-35) Very few of us operate at these temps. Transitions from motionless to flowing will vary with temp. Again, I'm lacking in some formal education links ..and the self taught process is challenging. So there are surely a few flaws here.
 

FZ1

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4,727
Location
Texas
Run the oem spec'd weight oil for your car. Synthetic flows quicker than dino. I wouldn't want to run too heavy a weight up there. It's cold!
 
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1,339
Location
USA
 Originally Posted By: jorton
Thick German Castrol can pour colder because it's made with a better class base stock.
Shhhhhhh! Your not allowed to say that here. The Group III Police will stop writing tickets and come after you.
 

ZZman

Thread starter
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6,987
Location
Michigan
The cold pour tests I have seen where they have oils side by side and then pour them out always have the oils way colder them normal temps. I would like to see the same tests at more reasonable temps like maybe one at 32 degrees and another at 0 degrees to see how well they pour. I did find this article that I thought was interesting reading: http://www.technilube.com/faqs_info/cold.php
 
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