LexVan

The OCI is set by the Marketing Department.

Reasons? How many UOAs have you studied??

LexVan

That's easy.

The SUS at 210F will be below 60 and the cSt at 100C will be below 11.

MidEngineRules

I'm due for an oil change in my MY16 3.8, still under warranty but don't want to use Mobil One. I want to change to Driven DI40 which is specific for direct injection motors. With all the cylinder bore issues coming to light as the 997 ages, I want an oil specific to combat issues to what they're seeing. I need to contact my dealer and see if they'll have issue not using a Porsche approved oil (simply because Driven isn't going to go to the expense of having Porsche approve it). LN Engineering swears by Driven.

As for the UK recommendation of 2 years, you're asking for cylinder scoring. If you don't use an oil specific to direct injection motors, then LN Engineering suggests 6 month oil changes. FWIW.

rnl

Ordinarily I would agree with you about engineering, however, a 10k interval is primarily driven by the need to comply with environmental laws and regs.
I change it every 5k or so since new and at 94,000 it does not burn any oil - I have no idea if my frequency of oil change is responsible for this

Thinc2

None. I have zero expertise in this area, which is why I'm following the advice of the manufacturer...

afk

Thanks for all the input

I am at 4500 miles now and note the oil level is now showing minimum level
and was originally thinking to add oil
but from the above info I will just change it out.

The only reason I checked the level was the other recent thread on oil level and oil consumption.

Thanks to all for the good info!

-A

shammerman

Exactly.

Bxstr

On my daily driver Audi, I do 7-8k miles typically. If I was daily driving a 991, I would probably do around 5k. But, I do 20k a year so if this was me I would be in at the dealer or independent getting oil changes every 3 months.

Jack F

Im not going to discuss oil changes intervals since what we do with our cars is our business. Could you please though do a used oil analysis on the 10k oil? There are many on this forum that would appreciate seeing the numbers and not many drive that many miles in 1 year or they choose to change earlier. I would find it very interesting especially if you us the M1 0W40.

ipse dixit

This.

So much this.

Cuda911

Every 3k to 4k miles. I am paranoid... I used to own a 996. I use my 991 as a DD, drive it approx. 9k miles per year. Other vehicles for the remainder of my driving, but the 991 is my preferred one.

LexVan

Here's the thing Jack F, you don't even need to go all the way to 10,000 miles on the Mobil 0W40 to see that it's fallen out of spec (sheers down to under a 30 weight) for that viscosity. This starts to happen even before 5,000 miles, hence the reason why many change early.

If you really really want to see these 10K numbers, there are examples here on RL.....but you have to search around for them. If I find/see some, I'll try to ping you.

Bottom-line, we don't know everything on this subject, nor do we need to, all we need to DO is take note of some of the very experienced engine builders and mechanics that have their hands on these motors daily (ie- Jake, Charles, and Kevin) and they all tell us to do much earlier and often oil changes vs Porsche's maintenance schedule. So, I don't need to know everything, I just need to know the people who do.

Lastly, I've thoroughly documented (Blackstone Labs UOAs) every oil change on my car here on Rennlist since early 2014. In that time, I have NEVER seen better/lower wear metals posted lower than mine. I've playfully challenged others to post better numbers than mine. I've had no takers yet. I am not taking any special credit for these great results. I am only taking credit for listening to those who are smarter than I am.

Bob Z.

The ultimate question though is does it matter? What I mean is that will the engine last longer if one changes the oil at 5k compared to 10k? I do not think anyone can answer that question because there are too many variables such as how the miles are driven, how long the engine runs each time, viscosity/brand of oil, climate, type of oil, etc.

Jack F

Yes those are variables that for sure play a role. I would have a tough time deciding to buy a 991.2 that used M1 0W40 that was changed every 10k. It is cheap insurance in my opinion. And I like doing it myself. I am going to use LiquiMoly 0W40 for the next 2 changes to see how the 40 viscosity holds up. In the 991.2, my opinion is that the M1 0W40 does not hold up as well as it should and I want something that holds up better at the upper end. I want to take the car on the track and be really comfortable. My 4 GTS is a keeper for me.

Bob Z.

I do agree that one should never exceed a year, no matter how few miles are driven.