Originally Posted By: BarkerMan
they have a Porsche and it has been recommended by their service writer in the tone of “you’re car will turn into a pumpkin if you don’t”
The car may not turn into a pumpkin, but the owner may be in a pickle.
I mean if the Porsche car is still under warranty it is crucial to use an oil on the list and as others have said M1 is the one readily available. Aftermarket warranty companies especially -and I assume manufacturer warranties also- often look for an excuse to exclude an expensive repair such as engine failure from the warranty.
From what I have seen and heard, most boxster and 911 engine failures result from intermediate shaft failures (wide range of years suffer from this poor single bearing design, some years have two bearings), slipped cylinder sleeves (older models), cracked blocks or heads. A few spun bearing stories out there also. The vast majority of engine failures are not a direct result of lack of lubrication, as others have said in other posts.
So my point for Porsches at least is it is important to use M1 or other oil on the list if still under warranty so that cannot be used as an excuse for someone to deny a claim, even though the oil would probably have nothing to do with the failure.
In terms of the service writer, it is amazing how their knowledge (or lack of) varies from one individual to another. Also some feel they need to spout the company line at first and will tell you something different if you really ask them about it or if they know you well. If you are out of warranty, you are free to try other oils. Personally I think the statement about "only one that works in a Porsche" is [censored] and I am open to the possibility there may be better oils out there and am actively looking/testing.
There are 3 M1 0W40 UOAs (5 runs total) from boxsters on this page fyi: mine showed what could be considered slightly elevated fe numbers and 30wt with tbn of 5.2 at 8700 miles (9 quart sump and 1 quart make up oil).
http://986forum.com/forums/showthread.php?t=14406&page=2&pp=20