I get a car diagnostics and oil change done at 2k then every 5k. Keeps me and the car feeling good. As others have mentioned, the engine runs smoother after an oil change....that may just be in my mind but I'm ok with that.

 

I'm not sure I read this correctly, but the 1st service is at 10k or 1 year, so it should never be longer than a year before the oil is changed.

 

It isn't but there was a comment at some point that in Europe it was 20K for some reason

 

Yeah I hardly believe the car actually runs smoother after an oil change.

I will agree with you I "feel" as if it does too (which is why I also change more frequently). It seem to run smoother and better after I wash and detail it .

But if it was significant enough for you to notice by driving, you'd probably have enough friction being generated that you'd have a host of other issues..

 

+1..

 

Yeah kind of like how the scientists said in the 50's that cigarettes were good for you.. And how radiation posed no real health risk..

I'm a engineer and scientist by training and trade.. expert advice is never a complete substitute for common sense..

 

Common sense is to follow the manufacturer's recommendation. Porsche AG are the only ones with the r&d to support their opinion. The rest of us are only guessing based on a body of knowledge that has limited applicability to today's oils and DFI engines. Has anyone seen an actual honest-to-goodness experiment/data on DFI engines and effect of different oil change frequencies?

The "it certainly can't hurt" argument that keeps popping up has severe and obvious limitations. Why not change the lug nuts, engine air filters, cabin air filters, brake fluid every year? Hey, while we're at it, let's change the spark plugs every 2 years and the tranny fluid every three years? Maybe by paying the technician to do unnecessary work, he will diagnose another problem early...

 

I changed the lug nuts. Got rid of those annoying locks.

 

Wow. You are right! I need to change my entire car every 2 years!

 

One year is a long time . Plus that's even assuming that the owner realizes the passage of time on an ultra low mile car .

Plus there is a bit of flawed logic . Let's say a driver only puts 700 miles on his car in an entire year . Does that mean the oil is bad ? How long does oil sit on a shelf in a store ? Does it make that much of a difference if the oil is on the shelf vs an ultra low mile car ? How about the person who goes out today and buys a 2013 leftover car ? Should he insist on an oil change ? Or how about a 2014 car that sits a year and is sold in December ? Is that oil no good ?

But the oil in a drivers car with 9.5K miles of hard driving is still good enough for 500 miles ? Not to mention the climate in any of this ? Does 9.5K miles of the little old lady driving on the highway with no traffic daily at 55 MPH to her retirement home in 50-70 degree dry climate equal the 25 year old pounding 9.5K miles on a hot and humid Sebring track ?

Why are some so complacent to question the merrits with such a huge range of disparities ?

Not to forget adding the 6 other reasons I listed on top of this .

 

Yeah wasn't suggesting other than that.. Just the mindless attitude of following and acceptance of things because some so called experts said so..

In this case maint recommendations are of course what should be relied upon.. Because porsche is of course the expert and in the best position to determine..

Scientists with an interest or paid to say something.. Not so much.. That's all..

 

[QUOTE=KonaKai;4057859]Common sense is to follow the manufacturer's recommendation. Porsche AG are the only ones with the r&d to support their opinion. The rest of us are only guessing based on a body of knowledge that has limited applicability to today's oils and DFI engines. Has anyone seen an actual honest-to-goodness experiment/data on DFI engines and effect of different oil change frequencies?

The "it certainly can't hurt" argument that keeps popping up has severe and obvious limitations. Why not change the lug nuts, engine air filters, cabin air filters, brake fluid every year? Hey, while we're at it, let's change the spark plugs every 2 years and the tranny fluid every three years? Maybe by paying the technician to do unnecessary work, he will diagnose another problem early...[/QUOTE]

I bolded two comments .

1) Do you firmly believe that Porsche AG R&D isn't fused with the objective of 1) selling cars and 2)establishing cost to own parameters within THEIR warranty period ?
If you paid 125K for the car who really owns it ? You or porsche AG ?

2) The second comment is a straw man argument . We can discuss each one of those parts separately but they are not related to the value and merrit of an oil change interval recommendation .

 

[QUOTE=yrralis1;4058079]Track use is a different story. Everyone, including Porsche in the maintenance manual, agrees that "hard use" follows a different schedule, so let's take that out of the equation. For the rest of us...

1. Porsche AG's (and the dealer's) sole focus is profits. That can come from selling cars, or from service. If they doubled the oil change intervals to say 5k miles, that would be a significant increase in dealer's profits (from service). From the sales side, would that also crimp sales materially? We can disagree on that, but I'm pretty sure it's a tiny group of 991 buyers that would walk away from the 991 purchase because the maintenance handbook has oil changes at 5k instead of 10k miles.

2. It is not a straw argument. In ALL these cases (oil and otherwise), you and I are everyone else on this board are purely hypothesizing on whether Porche's recommendations are strict enough, with no useful data whatsoever to back up our claims, whereas Porsche has actually gotten their hands dirty with the r&d.

 

There was an SAE paper I read that describes a test back in the mid 70's when Mobil first came out with Mobil 1 synthetic. Mobil oil first went to Ford to test the oil in daily use. Ford provided a new Lincoln driven by one of there management team. This Lincoln was garaged in Detroit where, for one year the executive drove less than one block before getting on the freeway where he drove to work for all 4 seasons. After one year with no maintenance or oil changes the engine was completely disassembled and inspected. Every single wear item was found to be within factory new specifications. Since that time Mobil has continued to improve their oil and the specifications of the oil has changed due to environmental requirements and changes in automotive manufacturing policies and procedures.


From day 1 through today Mobil recommends a maximum of one year between changes. One reason is because unlike the oil still in the container it is exposed to air, moisture and combustion by-products. Water in oil changes to an acid base and is the main reason why 1 year changes are recommended. The owner who only drives a few hundred or a thousand miles a year needs to change his oil more frequently because the oil never gets hot enough to dissipate the water vapor in the oil. All internal combustion engines produce approximately one gallon of water vapor for every gallon of gas consumed. Much of that water goes out the tailpipe but some of it gets in the oil.


Europe is a completely different discussion. Their requirements for oil are very different then in the USA and in fact I believe it to be much better. That may be one reason why Porsche has different requirements for change intervals in Europe.


I believe that Porsche is one of the best engineering companies in the world that happens to build sports cars instead of aircraft or rockets or . . . I'm on my 3rd Porsche and I've always tried to follow the Porsche recommended maintenance schedule. They know a hell of a lot more than I do about their products and the maintenance needs. Yes, marketing and sales all come into play but they are still the best at what they do.

 

Your first paragraph discusses a study done in the 1970's on a Ford engine with no evidence supplied to support it. Yet the claim is made that its true.

I am not a proponent of junk science because if I was I might buy into this more recent (2009) report in which Mobil 1 actually failed (link provided) . http://www.jobbersworld.com/March%2020,%202009.htm

Or discussions like this https://www.6speedonline.com/forums/997/149658-local-porsche-shop-told-me-mobil-1-has-been-known-damage-engines.html

I feel that the accuracy and merrit of the various research results is up to the one who questions.
I am not a scientist but I am willing to ask questions and they reveal many aspects (and debate) to this discussion.

I do agree on the point that you made about the engine oil properties being different than oil on the shelf but that was not my entire point . In fact I advocated frequent changes .My point was to show a huge disparity of engine use , driving style, and climate and feel that spending a few extra bucks on an expensive car to have a technician inspect it, document it , and place clean oil is minimal expense to help preserve a cherished vehicle.

I do feel Porsche is one of the best companies in the world. I currently have 3 Porsches and in total have owned 11.