Shearing and mobil 1 0w40

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Oct 14, 2014
So I have used mobil 1 0w40 for one OCI (4,000 miles) so far and Im doing the second oil change on it in a couple days, before I send it to be analyzed. I was reading the VOA of it and everyone was arguing about it shearing into a 30 weight....

Is this supported by anything? If an oil shears, does it protect less? I have nightmares about getting scored cylinder walls.

Post in question...

Am I worrying over nothing?
Yes you are worrying over nothing.
Firstly, M1 SN 0W-40 is actually heavier than necessary for your Audi so any oil shear or viscosity loss will actually bring your operational viscosity closer to optimum if anything.

Secondly M1 SN 0W-40 doesn't shear much at all in most applications.
If an oil shears it's viscosity is less but sometimes it has no effect on wear since there is sufficient viscosity reserve built into most all applications.
From the link, I stopped reading after Doug Hillary's post. No need to go farther.

M1's 0W-40 is one of the best engine oils on the planet. Run it. Longer too.

It has an HTHSV of 3.8. Let it shear.
No undue or excessive M1 0W-40 shearing during my ~decade of use, inspections and testing.

I run it through to the full manufacturers' time and/or distance recommendations with nary an issue in any of mine. Knock wood.

You'll likely have other pressing matters which may prompt "worrying" long before your M1 contributes to failed hardware lubrication.
Originally Posted By: Guitarmageddon
Am I worrying over nothing?

Also don't spend money is you are worrying about wearing only.
I all the time push the idea that UOA are useless for wearing detection: big metal pieces are catched by oil filter. You could had completely destroyed camshaft, but UOA woud be almost fine. Buy a magnetic oil nut, it will be more illustrative, IMO. But oil filter will still do his job.
UOA makes sense to catch the oil condition, how many additives left in the oil, how long could oil be used, etc.
If you see the significant drop of additives, ask youself where are they. If you have no idea, I'll help you: on your pistons and oil drainage holes as high-temperature deposits.
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