When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Wonder if Porsche would take some sort of remedial action, or at least send some warning, if this is any sort of concern for 991.1 owners now surfacing years later from a liability standpoint?
Wonder if they did anything for IMS 996 etc..
Outside of the Eisen class action lawsuit settlement, Porsche did nothing. They did offer for a short period of time a replacement bearing kit that used a ceramic hybrid single row bearing, but that part shortly was removed from the system and is not available for purchase any longer. I was hopeful that Porsche was going to release service guidelines when their bearing was released, but nothing was ever published and outside of those on the Porsche classic advisory board, I don't think many knew this part even existed.
Same goes for the Lokasil blocks and to a lesser extent the Alusil blocks. We know that they fail and why they fail. But no changes have been made to the new replacements offered by Porsche. It is up to the aftermarket to come up with solutions and provide support for these applications without acknowledgement of the issue by Porsche.
In the attached used oil analysis which includes data on both Mobil 1 0W-40 and Motul 8100 Xcess Gen2, you’ll notice that after 4K miles on the Mobil 1, the Viscosity index was 11.8. 12.6 is the minimum threshold for a 40 weight oil and M1 in virgin oil analysis is shown to start at 12.9 centistokes. That means from the start, Mobil 1 barely meets the description of a 40 weight oil. It is very thin from the start in order to improve fuel economy (which is what the factory likes to have sit up there for their CAFE standards). After 4K miles, the analysis shows that the viscosity index went down to 11.8 which means the oil has fallen out of grade from a 40 weight to a 30 weight oil. This is not great and perhaps why the metal wear numbers were up significantly over the Motul which had almost 5K miles on it. After 5K miles, the Motul’s viscosity index held at 13, so still a 40 weight oil. It did not shear out of viscosity. I’m no longer a Mobil 1 fan.
If you were to go back 15-20 years, you'll see my posts about M1 being consistently formulated to the bottom of the spec for a 40wt. And yes, we know it sheers down to a 30wt relatively quickly. This is great for fuel economy.
Like you, changing oils and doing used oil analysis will show how other A40 oils like LM 2040 or Motul 8100 X-Cess are superior to M1 0w40. If you go on the 996 and 997 forums you'll see many UOAs from people who have switched from an A40 oil to Driven DT40 or DI40 with even better results. The proof is in the pudding.
If you are dead set on using M1, using the C40 spec 0w40 is a much better option and provides superior protection from what I have seen compared to the A40 M1.
This is not necessarily correct. With respect to the four ball wear test, ASTM D-2266 is for grease and ASTM D-4172 is for oils.
I would just use the 4 ball test results as a reference point for an oil having a HTHS vis @ 150C and/or for use of friction modifiers, as the addition of latter will greatly skew the results. On its own it's meaningless, but I would expect an oil that does better in these tests to provide superior wear protection.
I would just use the 4 ball test results as a reference point for an oil having a HTHS vis @ 150C and/or for use of friction modifiers, as the addition of latter will greatly skew the results. On its own it's meaningless, but I would expect an oil that does better in these tests to provide superior wear protection.
Yes I am not even saying it's a test that matters -- just that it's not only for grease. In the end my own opinion is that I don't really care too much about how a given oil does in a myriad of tests because the test that really matters is the engine you run it in (although the former should be an indication of the latter). There is nothing better I have found than Driven DI40 but for sure M1 is an oil I would avoid even if it is a PAO ester blend. The proof is in the pudding just as you say.
I can’t remember if this applied to the IMS issue or bore scoring but weren’t the 991.1 turbos not effected by bore scoring? I have a feeling it was the IMS. If it was IMS then please ignore this post.
I can’t remember if this applied to the IMS issue or bore scoring but weren’t the 991.1 turbos not effected by bore scoring? I have a feeling it was the IMS. If it was IMS then please ignore this post.
991.1 turbos have Alusil engine blocks and can (and do suffer from bore scoring). No IMS though.
01-10-2023, 01:08 PM
