Well 199Porsche 911 is correct. Porsche currently lists 7 pages of approved oils I think 84 oils are on the list for all cars built since '84. TSB group 9, #1/05.

Only a small fraction of the oils listed are 0W40 (13) and Mobil1 one is only a small fraction of the approved oils (3). And not all approved oils are available world wide.
Some of the more familiar ones approved in North America are Castrol Syntec 5W40, Castrol GTX 5W-40, Mobil 0W-40, 5W-40, 5W-50, Agip 5W-40.

So make an educated decision based upon the use of the car and your climate. Porsche does not recommend a particular oil, it factory fills its cars with a particular brand but does that mean the racers running Amsoil or somethiing similar are fools?

Just my opinion.

Todd

 

Thank god finally somebody to put that to bed.

 

... for today!

 

I did notice that there is a sticker on the engine compartment hood that says "Factory Filled with Mobil One" or some such garbage. There's only one reason that Porsche uses Mobil One as a factory fill, and it's spelled out for you right there with the sticker.

$

I don't know the symbol for deutschemarks or euros or whateverthehell money they use over there this week, but Porsche did not put that little sticker on the car out of the goodness of their hearts. Exxon/Mobil paid dearly for that, let me assure you.

But hey, if you want to think that's what you should use, then by all means do so. You'll make the marketing guys at E/M very happy.

The stuff was $6/quart last time I looked. OUCH!

Michael

 

MJB, what do you use instead?

 

Exxon 20W50 dino oil. It's on the approved, er, recommended, er, uh, well, it's on the list.

Official OE filter though. And I was wearing my Porsche shirt and air-cooled hat (left over from my 993 days) when I changed it.

Michael (AKA MJB)

 

I just got back from the kitchen to get my popcorn and a beer, did I miss anything?

Tastes great! Less filling!

 

Ditto regarding 20/50 although I use Castrol. I've used it on all my Porsches since the 80's...running all of them to 200,000+ miles without issues. I haven't changed the oil in the 996 (I've put less than 1200 miles on since I purchased it) but I plan on using 20/50 in that as well.

I have a hypothesis, born of experience, that tells me thicker is better. This is a faith based hypothesis that I'll never try to prove for sure and, as long as I'm not disproven, will continue to include as part of my regular pcar maintenance.

 

I've thought about this more since posting the message. I used to use 20w50 in my C4 Corvette. It was a track rat, and I beat the overlovin'**** out of it, that poor thing. I bought the car new and at around 16K miles turned it into my track car, major engine work, suspension, brakes. I had all manner of issues (it was a Chevy afterall) and problems due to the abuse on track; wheel bearings, ball joints, lost the power steering hoses, some electrical stuff, but other than worn valve guides and broken valve springs, not a single ittybitty bit of engine problems, even after driving in sub-freezing weather at Road America and other early morning winter events with that heavy oil.

I'll never forget flying down the straights at RA at 120+ with snow blowing in the window. Brrrrrrrrrrrr.

Michael

 

How dare you people use an oil other than those approved by Porsche! I guess there are fewer zombies who blindly follow anything Porsche says than some thought. Some people on this board frown on those that actually use their intelligence and make decisions based on their own experience and knowledge rather than blindly following marketing hype.

 

Here's the thing (and out of curiosity): why do you think that Porsche recommends 0W-40 fill then? Mileage? HP? Seriously, what do you think?

And second, anecdotal evidence that's been espoused on here is fine and often worthy, but anecdotal evidence also was responsible for flat earth societies, bloodletting via leeches in medicine, mainframes instead of PCs, etc. I'm not trying to throw cold water on these experiences, but it's always worthwhile to question things.

 

Porsche DOES not push Mobil 0W40 at all. As a matter of fact, 95%+ of their approved list includes oils other than 0W40. Their factory fill is directly related to the amount of money Mobil gives them for using their product. That is not opinion, but fact and is a standard practice in the industry.

Yes, in theory, a thinner oil will improve gas mileage as well as power. That is, unless it causes burning of the oil. In an emsision compliant car, this means that all this burned oil is being expelled out of the exhaust AFTER it has passed through the intake. This means the octane of the fuel in your car is reduced and the inatke air is hotter (power loss). In the short run, a thin oil may give you more power, but unless it also provides the maximum protection against wear, it won't give you power as long as it should. Among the componants at risk because of too thin of an oil are, guides, seals, bearings and journals, and so on.

Many racers will use an ultra thin oil to maximize power, but their engines are rebuilt regularly.


BTW, blood letting was sound medical practice and has been proven to reduce risk of many ailments, including heart desease. This is the reason given why premenepausal woman have fewer heart attacks than do men.....due to their regular monthly bloodletting. Risk level for men who give blood several times a year, also have shown to drop to the level of woman.

 

You missed my point; why do most US Porsche dealers fill with 0W40? I mean, even in light of a relationship with Mobil, they clearly make other alternatives, like the aforementioned 20W-50 and also a 5W-50 version. Why not use that formulation?

I'm not even going to get into a discussion on bloodletting, but feel free to read this link from Wiki for more info.

 

Does a dealer care? Additionally. more and more dealers are using oil other than Mobil 0W40.

 

A dealer will likely do what Porsche recommends/suggests, though. I guess a study comparing the wear of an engine during average use in a cold and warm climate would be the only way to scientifically settle this debate.