My first try at using 0w oil....

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I'd be interested if anyone has ever pulled a valve cover off an engine, and timed how long it took various weight oils, before they reached the top end of the engine? (Rocker arms and such). After sitting overnight in below zero weather.

Nothing too scientific. Just start the engine in below zero weather, and time it with a stopwatch. 0W-20, 0W-30, 10W-40, etc. That would be good to know. Also if they could check the various cranking RPM's as well with these different weight oils. That is information that could be useful to guys like the OP, who are trying to select the proper weight oil to suit his cold weather requirements.

An old member named BuickGN and I did that years ago during the BITOG straight grade wars. Delo 400 SAE30 was on clearance for $.99/gallon and I bought a ton. The discussion was that straight grades did not flow well enough to lubricate an OHV engine below freezing.
I used my trail Jeep in my sig and pulled the valve cover off the AMC 2.5L 4 popper and started her up on a low 20-somthing degree day. Sure enough, oil immediately flowed from every rocker. I believe BuickGN did it with his favorite 20W50 with the same results.

Absolutely no scientific method used at all, just backyard "I see oil, it's good". I don't recall any difference in cranking sound but if there was, it was likely the drag of the 80W90 gear oil in the Muncie SM420 granny low transmission because it was started in neutral.
 
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I'd be interested if anyone has ever pulled a valve cover off an engine, and timed how long it took various weight oils, before they reached the top end of the engine? (Rocker arms and such). After sitting overnight in below zero weather.


 
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That took A LONG TIME! Far longer than I would have guessed. Well over a minute on the top video. It's amazing after watching that, these engines live as long as they do. You would think cold weather operation would kill them off far quicker than running in a warm climate.
 
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That took A LONG TIME! Far longer than I would have guessed. Well over a minute on the top video. It's amazing after watching that, these engines live as long as they do. You would think cold weather operation would kill them off far quicker than running in a warm climate.
It’s about the MOFT and all oils have sufficient MOFT at cold startup, whatever temperature that is. Again as long as the oil can be pumped.
 
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I don't think Michigan (I grew up in Flint and Burton) gets any colder than Iowa so 0W30 would be my choice for an engine that requires a 30 grade.
I would think the northernmost parts of Michigan which touches three Great Lakes and is maybe 300 miles north of Iowa, would be significantly colder. I know wind chill doesn't count for engine oil but still, Brrr...
 
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It's a smart move considering numerous long term weather forecasters, including the Farmer's Almanac predicting a tough winter in the Great Lakes region. Your car may never know the difference, except the better cold start flow.
What would be the better cold flow between, you pick the vendor, and a 5-20 v 5-30 weight oil? Wouldn't you need to be well below OF or colder to realize a difference?
 
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A 20-grade oil with a 5W winter rating is always going to be thinner than a 30-grade oil with the same rating. But both will meet the cold weather cranking and pumpability performance requirements for an oil with a 5W rating.
 

ZZman

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The answer is to run it and get back to us though you won’t notice much based on one oil change.

The engine calls for a 30 grade, why not run 0w30 if you really want to run a 0w oil?
I figured 0w-20 probably wouldn't hurt. Plus 0w-20 HM oil is easier to find.
 

MolaKule

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A 20-grade oil with a 5W winter rating is always going to be thinner than a 30-grade oil with the same rating. But both will meet the cold weather cranking and pumpability performance requirements for an oil with a 5W rating.
Exactly.

And why not a 5W20 instead of a 0W20? A 5w20 has a higher percentage of base oil with less VII.
 

MolaKule

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I would think the northernmost parts of Michigan which touches three Great Lakes and is maybe 300 miles north of Iowa, would be significantly colder. I know wind chill doesn't count for engine oil but still, Brrr...
You have wetter snows than we because of lake effect moisture, but who knows what this winter will bring.:unsure:

I recall the first winter living in Iowa (Dec. 2006) and I had a 10W30 HM in my '03 Pathfinder and it started up just fine at -30F sitting outside on the parking lot.
 

ZeeOSix

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I'd be interested if anyone has ever pulled a valve cover off an engine, and timed how long it took various weight oils, before they reached the top end of the engine? (Rocker arms and such). After sitting overnight in below zero weather.
This has been talked about a lot in the past with lots of links, tables and graphs. When you look at the data, the delay time to the top end is basically due to the pumpability of the oil to the pump inlet. Once the oil becomes fully pumpable by the positive displacement oil pump, then the flow is basically the same from the output of the pump, ie: the pump is pumping oil volume at or very near it's design capability. You can see it in the oil pressure curves of the test data of cold start studies. Once the oil becomes fully pumpable the rate of oil pressure build up (a function of oil flow volume at a constant oil viscosity) basically has the same rate on the oil pressure vs time curves.

If an oil isn't very pumpable, then the pump will not move the full volume of oil, and as a result the oil flow to various parts of the engine will take longer, and the time to build full oil pressure will increase too.
 
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You have wetter snows than we because of lake effect moisture, but who knows what this winter will bring.:unsure:

I recall the first winter living in Iowa (Dec. 2006) and I had a 10W30 HM in my '03 Pathfinder and it started up just fine at -30F sitting outside on jinthe parking lot.
I was just looking at a map of the USA and came to what I thought was a logical assumption. I don't live in the US, I live in Montreal and even here winters are not what they used to be. I hope I haven't spoken too soon, don't want to jinx it. Cheers.
 
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So.... What makes one oil more "pump able" than another of the same weight or Viscosity?
Pumpability really refers to the ability of the oil to be pumped and not gel in the vicinity of the pump pickup. As long as it makes it to the pickup it will be pumped. This is the very reason SAE J300 was revised years ago because although some oils should have been pumpable due to their pour point, there were engine failures because of shear induced gellation at the pickup. So either an oil is pumpable or it is not. The energy required to pump the oil goes up with decreasing temperature of course but this is temporary as the oil temperature increases.

The winter rating of the oil is what guarantees an oil will be pumpable at low temperatures.
 
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