0W-20 vs 5W-30 synthetics in cold temps

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I have two jugs in my stash right now.

One SuperTech 0W-20 HM, and one Pennzoil Platinum 5W-30 HM.

Engine is a Honda 3.5 V6. Burns a bit of oil, maybe 6/10ths of a quart every 3,000 miles. Car calls for 5W-20.

Mileage is approaching 150,000. I'd like to start running 30 weights for film strength, but with the cold weather almost here (coldest mornings for me are about -10 degrees F. Not crazy cold, but still cold).

That said, I don't want to run the 5W-30 weight in the winter if it's going to induce extra wear as cold start-up over the 0W-20. At those temps though, is there even really a difference in pumpability, or does that really only matter once you start getting to more like -40 degrees with synthetics?
 
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GM used to recommend switching from a 5W-XX synthetic to a 0W-XX synthetic at temps below -20F.

I would say that you are fine with a 5W-xx, but you are getting close to the point where a 0W-xx could be beneficial.
 

cheesepuffs2

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GM used to recommend switching from a 5W-XX synthetic to a 0W-XX synthetic at temps below -20F.

I would say that you are fine with a 5W-xx, but you are getting close to the point where a 0W-xx could be beneficial.
Is there actually a difference between the two at less than that -20 mark? Or do they act the same up until that ceiling where then the 0w becomes required?
 
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GM used to recommend switching from a 5W-XX synthetic to a 0W-XX synthetic at temps below -20F.

I would say that you are fine with a 5W-xx, but you are getting close to the point where a 0W-xx could be beneficial.
Yes, they still do in some cases. This from the Chevy 2500.

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Pennzoil synthetics are very good in the cold. Had PP 5W-30 in last winter, and right down to a true -30C air temp my car fired up with no drama at all.
 
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A quart every 4k or so isn't bad. -10f is an artic blizzard to me so I'd use 0w-20 and use the 30 in the warmer season and alternate between the two. Difference isn't massive but it's there at that low temp. At 30f like I'm used to it does next to nothing. 15w-40 pumps just fine in these warm winter temps. It's only when it got down to almost 10f where i started to have some issues cranking it over but it was probably my old battery at the time.
 

ZeeOSix

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I'd like to start running 30 weights for film strength,
Viscosity has nothing to do with "film strength", but does have a lot to do with the "film thickness" (MOFT) between moving parts. Yes, I know what you meant though. ;)
 
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I will use M1 0W40 in my 3.5 Honda this winter, this is Canada and I'm expecting -35°C/-30°F. Just because I had that in my stash.

From previous winter experience in my Mazda, 0W20/0W30/0W40 didn't make much of a difference. Never tried a 5Wxx in the winter.

In your case if you don't want to split the difference and buy some 0W30 I'd use whatever you have, if the coldest coldest you're expecting is -10°F. With a battery (and starter) in decent shape I don't think you'll notice much of a difference.
I would say that you are fine with a 5W-xx, but you are getting close to the point where a 0W-xx could be beneficial.
+1
 
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I live in the southeastern US and switched my Integra to Mobil1 0w-30 at least 15 years ago. This was after reading the Dr. Haas articles about oil viscosity and oil pressure at cold startup vs. operating temp. My car has 381,000 miles on the original drivetrain, all original internals, never rebuilt. I've put nearly 300,000 of those miles on the car myself. So, it must be working out okay. :)
 
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I live in the southeastern US and switched my Integra to Mobil1 0w-30 at least 15 years ago. This was after reading the Dr. Haas articles about oil viscosity and oil pressure at cold startup vs. operating temp. My car has 381,000 miles on the original drivetrain, all original internals, never rebuilt. I've put nearly 300,000 of those miles on the car myself. So, it must be working out okay. :)
You’re attributing the longevity of your engine to the winter rating of the oil? In the southeastern US?
 
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You’re attributing the longevity of your engine to the winter rating of the oil? In the southeastern US?
well apparently the writings of Dr. Haas on here are known to be outdated and in some cases incorrect. I wasn't aware of that until just now.

But, at this point with this many miles on the engine, and having just gotten a good UOA back this week, I ain't changin' it. Mobil1 0w30 for as long as I can get my hands on it.
 
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I'm leaning more towards the 10W30 synthetics now for GDI engines - may substitute 1 to 1.5 qrts. of same brand 5W30 synthetic oil during colder months .
 

Jackson_Slugger

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GM used to recommend switching from a 5W-XX synthetic to a 0W-XX synthetic at temps below -20F.

I would say that you are fine with a 5W-xx, but you are getting close to the point where a 0W-xx could be beneficial.
Prior to DEXOS, it was either 5W-30 syn or 0W-30 below -22F IIRC...
 
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Jackson_Slugger

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I have two jugs in my stash right now.

One SuperTech 0W-20 HM, and one Pennzoil Platinum 5W-30 HM.

Engine is a Honda 3.5 V6. Burns a bit of oil, maybe 6/10ths of a quart every 3,000 miles. Car calls for 5W-20.

Mileage is approaching 150,000. I'd like to start running 30 weights for film strength, but with the cold weather almost here (coldest mornings for me are about -10 degrees F. Not crazy cold, but still cold).

That said, I don't want to run the 5W-30 weight in the winter if it's going to induce extra wear as cold start-up over the 0W-20. At those temps though, is there even really a difference in pumpability, or does that really only matter once you start getting to more like -40 degrees with synthetics?

The main issue with cold start up wear has nothing to do directly with (thick vs. thin) if using quality syn base stocks. It is the acidic compounds that form from the water vapor created as a biproduct of internal combustion; it's something astoundingly never acknowledged here. There isn't a huge difference either way, just like there isn't a huge difference in high temperature wear based on the weight of the oil.

But I do prefer 0W-20 in the appropriate application in cold weather as there was a noticeable difference in idle performance and at startup of my previous car (also calling for 5W-20). But the real issue is that engines struggle to get to op temp fast enough to douche these acidic compounds from the crankcase...
 
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At -20 I'd be using 0W30, just in case. In the event it dips a bit lower I wouldn't worry about my OCD kicking in possibly driving me nuts.
 
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