Dock

I checked with a friend at PCNA concerning the Porsche recommended maximum oil change interval listed on their web site (the information you are citing), versus what is in the owners manual. Specifically, I asked him why the web site lists 12k miles while the owners manual lists 15k. Here is part of his e-mail reply (his first sentence is referring to the Porecheusa.com web site)...

"We intend it as a printing for generalization on porsche.com/usa. The more specific technical explanation to our dealer organization is as described in the attached Maintenance Schedule bulletin for the 911 Turbo."



Here is page 1 of that Maintenance Schedule bulletin he attached:



According to the bulletin provided to their dealers, Porsche recommends a maximum of 2 years between oil changes if the car is driven less than 9000 miles during that time. For cars driven more than 9000 miles/yr, they recommend performing the 15k mile service (which includes an oil change) when that mileage is reached.

Dock

Might that have been a few years ago? Just maybe the oil and engine technology are both better now.

"detroit iron" being the key here. Not sure "detroit iron" can be fast forwarded to 2011 and applied to a 996 Turbo.

I have a car that has over 160k miles on it with oil changes averaging WAY over 3,000 mile intervals (it has gone over 10k miles many times). The car runs great.

I have another car that has almost 400k miles on it with an even longer oil change mileage interval (it has gone over 10k miles between oil changes many times) . It also runs great.

neanicu

I heard this from mechanics : if it's a lease leave the oil for 10K,if it's yours change it sooner. I think it sounds a little wrong....I'm more interested why Porsche technicians tell me to leave it without a problem for at least 10K,while most of the people,including independent mechanics with lots of experience tell me to change it sooner because they've seen over the years how 10K oil is looking and it's not good. I guess nobody knows the Universal Truth....
Btw,I heard somewhere that you're supposed to change the oil soon after using the Chevron-Techron fuel system cleaner...is that true?

SimonK

Of course your mechanic tells you change it earlier it's more $ for him and more $ for the oil which he charges you commission for or receiving rebate. I think if Porsche says 15k, 10k is common sense to be on the safe side. If you do it at 7.5k you like your piece of mind. If you are really protecting your engine more is questionable. Under 7.5k I think unless tracking your car you are definitely into paranoid category.

Danyol

But wait! Then Porsche could make money for their dealerships shortening service intervals!.., hang on that doesn't work either....

DOC - with all due respect, Porsche are showing no consistency here; am I reading correctly the service bulletin is from 2006? I still maintain if their position is longer intervals they should update the chart on their website (attached). I can see the quandary they're in though, with additives being removed from their primary recommended M1 and they would have to admit their earlier recommendations could be causing premature failure (only they have the historical warranty data)

Simon, this has been a good discussion but put me in the "paranoid" category

- I replace my own oil <5k miles or 1 year (cost <$100)
- There is anecdotal evidence (on here and other forums) to exercise caution
- Engine >$20k; false economy
- I run M1 TDT 5 w40; the engine makes different mechanical noises at start-up, why?
- These (public) discussions over and over again will have an impact on prospective buyers - shorter oil change history leaves nothing in doubt.

I think this dead horse has been beaten enough now, we can reconvene on this topic a few years from now.

SimonK

5k Danyol? I will just call you slightly paranoid. I change at 10k and use 10w60 Castrol Edge. So I guess I gain some protection with big weight numbers to of set my "long interval". . Agreed interesting debate.

Dock

I'm just the messenger. If you have problems with what Porsche recommends, take it up with them.

My PCNA source is a high ranking officer in the organization, has a degree in engineering, and has been to the Porsche Mechanics School. He can get answers from the source (PGA) by just picking up the phone and calling them. I trust what he says.

Danyol

Dock, my comments weren't directed at you, I always appreciate your insight.

I'm probably more concerned about Porsche and their direction, this is a forum to air/share opinions besides share in the joys of ownership (we know what they're worth!). With Porsche UK recommending 20k intervals, Porsche US 10, 12, 15k (or whatever it is) that is a big span. In 2006 I owned a C4S that lost an engine at 19k miles (intermediate shaft), maybe I'm more sensitive than most.

Dock

Thanks, and not to worry; I didn't feel targeted