Last time I checked MC 1701 was feb, did that oil get added to the approved C40 list?

Im no Porsche Master mechanic or anything, but I think you will be fine. I'd get it changed, but I wouldn't not drive the car.

The MC-1701 document confirms that Mobil 1 ESP X4 0W-40 is C40-compliant for Porsche vehicles starting from model year 2021. This means it meets the specific requirements set for oils used in these vehicles, particularly those equipped with gasoline particulate filters (GPFs).

Key Details

• Oil Type: Mobil 1 ESP X4 0W-40
• Compliance: C40-compliant
• Applicable Models: Porsche vehicles from model year 2021 onward

This compliance ensures that the oil is suitable for use in newer Porsche models, adhering to the necessary performance and environmental standards.
siberian

I will add that US vehicles do not have GPF's and despite extensive conversations with Liqui Moly engineers given the restriction on Mobil1 0w-40 C40 oil at the time it wasn't clear to either of us what specifically mandated C40 compliance given the above. HOWEVER given it is specified they recommended we live with it. My only drawback is that given it's 5w-40 I can't drive it if it's below -20F.

If you do a search on the forum, you'll see a summary of this odyssea 5 years ago or so.

siberian

So I called the indy this morning and they were adamant that A40 is fine because it is a US car and doesn't have GPF, that they've been using it on all their 992s including the GT cars for years with no issues. I mentioned the manual and Porsche specifications, and they said that was mostly for emissions purposes. For those of you more knowledgeable than me, any validity to what they are saying? Even still, it worries me for warranty and resale purposes to use a non-recommended oil.

Yes and no.

Yes, our cars do not have GPF's as I mentioned above. HOWEVER because P did not issue a disclaimer stating that C40 oil is not required for US vehicles, Liqui Moly engineers advised in case of any "issues" to stick with what the manufacturer recommended.

Lastly we don't know (and the indie certainly doesn't) if the reason for C40 extends beyond GPF's and specifically what mods were done between the 2020 engines and 2021 to require this.

I would urgently look for another indie (or do it yourself) as what they have or not used for years is irrelevant in case of a claim. There is no excuse for it irrespective of whether our cars have GPF's.

siberian

How nice of them to decide for you that you don't need to follow the manufacturers recommendations.

Call me old fashioned but I use C40 oil per the Porsche spec. That way if there is any issue I know I did things "by the book" rather than what a random non-porsche engineer said.

A lot of people here complain about mobil 1 oils but I've run cars to 250k+ miles on book intervals with no problems.

I use C40 just not Mobil1 (Liqui Moly); though I use that oil (A40) on my skid steer and LC200

siberian