RandyVW

Without starting an oil war, any other So Cal folks around here know we've had a cold/wet winter. This will be my first summer w/ my 997 and curious as to going from M1 0w40 to a thicker oil is a good idea. (We often reach over 100 here in summer). In this link in particular ------> https://bobistheoilguy.com/forums/th...vs-5w40.350812 .....I see preference for 0w40 even at the cost of weight, presuming its formulation is better. (I know there's an M1 5w50 as well, which I'd opt for if it's considered a better formulation than whatever's missing from 5w40.

Some comments in the thread that caught my attention.....

• Mobil 1 FS 0W-40 is clearly the superior product. I can only assume that FS 5W-40 exists because some people think 5W-40 is superior to 0W-40 and Mobil was losing market share. FS 5W-40 hasn't "replaced" FS 0W-40.

• The 5W40 tends to be a bit thicker, while the 0W40 tends to use a bit more PAO (but this could change)

• While I agree the link above only list A3/B3 for the M1 5W40 (not the better A3/B4), I believe this is a typo, as you can't get Porsche A40 approval or MB 229.5 approval without being A3/B4 first. It's part of their requirements.

• Anyways, M1 0w40 > M1 5w40, any day of the week. Plenty of UOAs and VOAs to back that statement though it is not the most scientific backing available.

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P.S. I'm not interested in other oils, I plan to stick w/ M1 though I know there are other great oils out there. Just curious as to whether a move from 0w40 for summer is wise and if 5w50 is maybe better than 5w40? (not so much for weight as for quality of content)

TIA

Petza914

Whichever M1 you choose, change it every 3k miles. It's shot after that.
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Carreralicious

I used M1 5W-50 for several years in my 997.1S cab and had no issues, and I live in the NE. Then, I switched to Motul 8100 Xcess Gen2 5W-40, and have been on it for a couple years now. I think it’s a better oil overall and want to stick with a Porsche A40 approved oil. I noticed that the oil consumption in the car almost halved after using the Motul. I have about 55K miles on the car now and put about 5K miles a year on it.

Bruce In Philly

2009 C2S 197K miles

Makers have been moving to thinner oils for a long time... gas mileage, emissions, regulations... whatever else are the reasons, IMO... it is just too thin. Of course, engineers can engineer for just about anything, but I use 5W and change every 5K miles. I also add Ceratec, a moly and ceramic friction reducer. It entertains me, no real science. I could never get M1 5W in big jugs so I moved to a LiquiMoly A40.

Your manual denotes oil options and these options can be run anytime anywhere.

Peace
Bruce in Philly (now Atlanta)

RandyVW

Thanks guys! I can get jugs of almost anything here in So Cal so not an issue but most curious avoid any validity if 5w40 “lacking” some advantage that 0w40 has.

im leaning toward just going 5w50 since they’re all pretty thin anyway and on a 100 degree day here in So Cal I think I’d almost feel better that there’s 50 at the upper end of hi temp scenarios. 🤷‍♂️

And to Bruce….ya I’ve seen most folks tear into the additive stuff. I’d probably just leave the oil be but I do run Lucas in my VW motors (not your typical Type 1 motor) despite using 20w50 VR1 as my base oil. I can’t prove a difference but we’ve got several motors with lots of miles on them so I don’t discount additives entirely. 😉

ADias

5W40 works.

ATX_Native

5W40