OVERKILL
$100 Site Donor 2021
BTW, 5,650cP is heavier than 5,553cP (the 0W-30), so I'm not sure what the point of that screenshot was 
Would you use 0W30 instead of 0W20?
- Thread starter 57_Chevy_Thunder
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Try again, the post right above this one of yours proves the CCS of HPL 0w30 is lower than the Castrol 0w20. However, you clearly don’t understand the distinction between cold cranking simulator and pumpability. As was noted earlier, if an oil is pumping, it is protecting, even if it’s thick.
Yeah, it's clear that the the two 0W oils (one a 0W-20 and one a 0W-30) @OVERKILL posted a few posts above makes it clear that both 0W are essentially the same CCS viscosity at -35C.
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I'm thinking there isn't quite a fully understanding that the "W" (0W, 5W, 10W, etc) grade is a whole different and separate viscosity measurement than the "20" or "30" KV100 viscosity. There are probably even 0W-40 oils out there that have very similar "W" grade CCS viscosity as the 0W-20 and 0W-30 oils.
OVERKILL
$100 Site Donor 2021
Yea but what happens when those coatings wear off? And they do.
It might be right there - - - but it IS LOWER when comparing name brand synthetics - - - -not some expensive boutique oil that only .0000001% of the driving public uses.
Take castrol for example
0w-30 https://msdspds.castrol.com/bpglis/...PDS CCSA Castrol EDGE w FST 0W-30 english.pdf
0w20
https://msdspds.castrol.com/bpglis/...305276F8025808B0047EB89/$File/BPXE-AHH32P.pdf
The 20 weight is lower at -35 vs the 30 - - - - - not by much but it is lower - - where it diverges is the -40 temp.
Anyway - - - - Im done providing evidence in this thread and betting bashed for it.
If you think a thicker oil will pump better in the same temp as a thinner oil - - cool.
Pumpability is a binary and is illustrated by the winter rating. If it pumps, it will pump. A thicker oil will take an incrementally higher amount of energy to pump but even then it is transitory since the oil heats up rather quickly. And the thicker the oil is the faster it will heat.
You seem to be stuck on the notion that thinner oil protects better at startup which isn't true. A thinner oil never "protects" better, ever. Both these oil examples will pump and protect.
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I don't think anyone is bashing you. There are 2 separate points being made here:
1) there are some thicker 0w-30 oils which pump better than some 0w-20 (you made a generic statement like "a -20 will always protect and flow better than a -30, this was proven false.)
2) the 0w-30 always, at all times even when cold, offers more protection than an otherwise equivalent 0w-20, as long as it is pumping.
Here are your Castrol examples, specs shown below from the spec sheets. Actually, the 0W-30 has a hair lower CCS viscosity at -35C. They are both almost identical 0W rated CCS viscosity. Both will pump essentially the same because one is 5897 cP (the 0W-20) and the other is 5800 cP (the 0W-30) at -35C. There is no evidence seen here that one is better than the other, or even better than any other 0W spec sheet posted previously. In fact, the two Castrol Edge oils you linked both have thicker CCS @ -35C than all the other previous 0W grade oil's posted previously in this thread.
As said before, if any oil is rated as a "0W" then it's going to pump in a cold start-up essentially the same as all other "0W" rated oils. That's what the SAE J300 "W" (winter) grade rating is all about. Don't know what you're trying to prove otherwise with "evidence".
Castrol Edge 0W-20.
Castrol Edge 0W-30.
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If it makes you feel better go ahead with 0w30 vs 0w20. There might be some minor fuel economy differences but that's about it. It will be something less than 2% for sure, more like 0.5-1.5% usually.
They should be designed to last the life of the part. I mean, take the bearings for example. People have torn down BMW B58 with 100k miles and the IROX coating is still looking like day 1 on the rod bearings. I’m not as familiar with the various piston skirt and cam coatings etc but I would say any coating failure is a design flaw. Every part has a MTBF target, coated or not the OEM expects x miles out of a part. Would you use these coatings in a million mile design? Maybe not, but we’ve seen enough bad cam surfaces, bearings, etc. before the coatings became popular already. Everything is a wear item given enough time.
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FYI Honda CR-V -- in Japan the owner's manuals list an acceptable oil weight range of 0W/20 through 5W/30
And Japan has their own kind of "EPA/CAFE" thing going on and they still allow a range of viscosity.
Holy Necropost, Batman.
I’m seeing a lot of misunderstanding about cold viscosity. The W ratings are just points at a given temperature. The J300 defines certain max viscosities at reference temps. If you’re within the do-not-exceed box, you get to call your oil that “w” value.
But it’s just one point on a curve. And the shape of the curve on either side of that point really matters. @ARCOgraphite posted this awhile ago and everyone seemed to gloss over it. A 0w-20 and a ow-40 do NOT have the same cold weather performance just because they both happen to get under the bar for 0w at one test temperature. The have very different KV40s and take very different paths to get to their respective viscosities.
Which means the real question comes down to this: if two oils will both pump at identical temperatures, but one has lower viscosity all the way from that temp up to operating temp, is that a good thing or a bad thing?
What the last few seconds of this video where the technician explains that CCS does NOT measure the abllity of the oil to flow thorugh internal oil passages:
In other words, the faith that the two 0w rated oils are identical in tems of of startability and starting wear just because they have similar CCS is unfounded. The CCS (as the name suggests) simulates the ability of the engine to start, not the ability of the oil to flow per se. It’s the “apparent viscosity” that CCS measures.
Regardless of CCS, the ow-20 is going to flow through the engine faster than the ow-30 at every temperature above -35C because it has lower viscosity at every temperature above -35C.
Yes, it may be that thicker oil shears more than thin oil and so will warm up slightly faster. But it’s not warming up so fast that it ever becomes thinner, obviously if it did become thinner at any point, it would cease to have the same viscous heating the created the faster warmup.
So the thicker oil won’t have a flow advantage over the thinner oil in the cold starts scenario, even if they’re both 0w rated.
Now, of course there is a boundary line that divides grades, so as you approach that boundary, you can have some crossover effects where a 9.3 30 grade and a 9.0 20 grade actually have the KV40s reversed relative to the KV100s. But that’s sort of the exception that proves the rule.
If you are using an engine and planning on lots of dead cold starts in cold winter conditions, use the thinnest oil the OEM allows. And that means by KV100, not just “w” rating.
I’m seeing a lot of misunderstanding about cold viscosity. The W ratings are just points at a given temperature. The J300 defines certain max viscosities at reference temps. If you’re within the do-not-exceed box, you get to call your oil that “w” value.
But it’s just one point on a curve. And the shape of the curve on either side of that point really matters. @ARCOgraphite posted this awhile ago and everyone seemed to gloss over it. A 0w-20 and a ow-40 do NOT have the same cold weather performance just because they both happen to get under the bar for 0w at one test temperature. The have very different KV40s and take very different paths to get to their respective viscosities.
Which means the real question comes down to this: if two oils will both pump at identical temperatures, but one has lower viscosity all the way from that temp up to operating temp, is that a good thing or a bad thing?
What the last few seconds of this video where the technician explains that CCS does NOT measure the abllity of the oil to flow thorugh internal oil passages:
In other words, the faith that the two 0w rated oils are identical in tems of of startability and starting wear just because they have similar CCS is unfounded. The CCS (as the name suggests) simulates the ability of the engine to start, not the ability of the oil to flow per se. It’s the “apparent viscosity” that CCS measures.
Regardless of CCS, the ow-20 is going to flow through the engine faster than the ow-30 at every temperature above -35C because it has lower viscosity at every temperature above -35C.
Yes, it may be that thicker oil shears more than thin oil and so will warm up slightly faster. But it’s not warming up so fast that it ever becomes thinner, obviously if it did become thinner at any point, it would cease to have the same viscous heating the created the faster warmup.
So the thicker oil won’t have a flow advantage over the thinner oil in the cold starts scenario, even if they’re both 0w rated.
Now, of course there is a boundary line that divides grades, so as you approach that boundary, you can have some crossover effects where a 9.3 30 grade and a 9.0 20 grade actually have the KV40s reversed relative to the KV100s. But that’s sort of the exception that proves the rule.
If you are using an engine and planning on lots of dead cold starts in cold winter conditions, use the thinnest oil the OEM allows. And that means by KV100, not just “w” rating.
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Done a few myself.Seen worse Necroposts.
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