Larry, you are referring to a Pour Point Depressant, not a VII. Different molecules, different results.
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BUMP ... maybe a mod/admin would consider making this thread "sticky"?
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Larry, you are referring to a Pour Point Depressant, not a VII. Different molecules, different results.
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So can anyone explain to a newb how 5W-20 oils compare to 5W-30 oils when hot?
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Larry, you are referring to a Pour Point Depressant, not a VII. Different molecules, different results.
No he is NOT talking about PPD's. He is referring to starting with an extremely thin oil that would be significantly thinner at startup than even a 0w rated oil, then adding VIIs to make it act like a 30wt oil at operating temp. If he were talking about PPD's, he would have said "why not add something to a 0w-30 oil to make it like a -5w-30" or something of the like. Reading is Fundamental.
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And yet why does it make valve train noise.
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However, what this entire analysis ignores is the viscosity shear-down at operating temperature that occurs in all oils using VI improvers. The more improvers are used, the faster the shear-down. 0W-30 will have more VI improvers than 10W-30.