2004 986-5 speed

[Ubuster1]

I’m doing my first oil change on my 04 986-57K miles. I live in bethel Connecticut. In my trunk there is a Mobil 1 sticker. I’m getting mixed reviews on the viscosity and brand of synthetic oil. One group of friends “owners” are telling me Mobile 1 European 0-40. My neighbor who had his 911 serviced by Danbury sport group Speed Sport Tuning uses only Liquid Moly 5-40. In your experienced opinion what do you suggest or not a big difference. Thank you 

Edited November 27, 2020 by Ubuster1

[ttocs]

I chose to stick with Mobile1 0-40. Never had any issue, never used more than 1/2 liter between changes. Only sent one sample in for testing which showed that the oil was good for a lot more miles/time.

 

I never got around to trying the Joe Gibbs DT40, but it's the only other one I would be willing to try.

[mikefocke]

There must be as many opinions as there are P-car owners. For more than you ever wanted to know, visit https://bobistheoilguy.com/forums/

 

[lkchris]

I think once you find "Porsche A40" on the bottle your search can be over.

 

Liqui Moly appeals to me a little more than Mobil, but both meet the standard.  Viscosity is irrelevant.

[JFP in PA]

On 1/13/2021 at 6:59 PM, lkchris said:

  Viscosity is irrelevant.

Not even remotely correct in this world.  But I would agree that Porsche's A40 spec is irrelevant as it is a marketing tool, not a lubricant specification. 

If you want real specs, consider products that meet or exceed ACEA A3/B3/B4, which are real, technically based and widely accepted performance standards.

[mcmike27]

Driven DT40.... after talking to Lake Speed at TechTactics for several years it's all I use now in my 2001 S...when the Macan needs its next change at 60k...it will be DI-5W30...

 

Just my $.02

 

Cheers 

 

m2

[Silver_TT]

Another vote for Driven.

 

In my engine, which is very similar to the Macan's small displacement turbo-charged engine, I'm running DI40.  Also all I use now after spending countless hours reading academic and industry research on tribology, LSPI, etc.  If you go over to LN Engineering's website, Charles actually purchased an LS-1 engine and is running it non-stop until destruction -- these people are my kind of testers.

[lkchris]

On 1/13/2021 at 5:11 PM, JFP in PA said:

Not even remotely correct in this world.  But I would agree that Porsche's A40 spec is irrelevant as it is a marketing tool, not a lubricant specification. 

If you want real specs, consider products that meet or exceed ACEA A3/B3/B4, which are real, technically based and widely accepted performance standards.

I believe you're misinformed (actually misinforming) on this.

 

As you surely know, the major German manufacturers all publish motor oil specifications which oil manufacturers must prove they meet.  It's a formal process.    Of course ACEA specifications are included.  The fact is, any motor oil that meets the Porsche spec will be a full synthetic and meet a viscosity requirement.

 

I once researched Mobil 1 products and learned that the cold pour points of 0W, 5W, and 10W versions were exactly the same.  That's all that's of much importance regarding the W number in a viscosity specification, that is cold start ability. I'd not spend a nanosecond wondering which I should choose.  The warmed up running number provides few realistic choices as regards 986 and these of course will be either 30, 40, or 50.  (BMW sometimes likes 60)  Again, if the product meets A40 the viscosity will be usable.  986 engines are a little older obviously, but in 2021 Toyota for some models specifies a 0W-16 motor oil and you can take to the bank it isn't going to fail in Death Valley.  Neither they nor any other other manufacturer are blatantly or otherwise attempting to have your motor wear out prematurely--that's grassy knoll conspiracy mongering devoid of intelligence or interest.

 

Experience indicates that it is typical self promotion felt needed by mechanics to dismiss factory engineering, in this case motor oil specifications.  Typically, as again here, without technical supporting detail.  I suspect it's especially ego satisfying and impressive to novices to recommend exotic things like Joe Gibbs oil.  My response is if any of you are petroleum engineers, you'd have a better job.  To blame bean counters or marketers is again typical nonsense.

 

PS:  ok, this is Porsche and we can all have lots of fun.  If yours is a track day only vehicle, have fun using an exotic oil ... in fact have fun using it in a daily driver.  The statement that A40 is all you need to know is accurate for most driving conditions and probably Porsche has set you free to do what you want for racing, as it doesn't accept responsibility for that in any event.

 

PPS:  these comments strictly about motor oil, other contributions on mechanical issues long appreciated.

[Silver_TT]

He's not misinforming people.  His statements are corroborated by industry and academic research.  If you are interested Lake Speed, Charles Navarro, and Jake Raby have done a lot of publishing on this topic.  Not all oils are equal just because they are on an approved list and in fact if you look at virgin oil analysis they vary widely in their composition.  Oil companies have to pay to be listed and the process isn't as objective, or "formal" as you put it, as you might think.  Viscosity is just one of many variables.  I started studying this about a year ago when I discovered my timing chain was severely "stretched" and I can tell you that I have come to the same conclusion independently.

 

Anyway, for all the people with knowledge about cars on the internet John has probably exhibited the least self promotion of anyone I have ever seen (he owned a shop but I couldn't even tell you what the name was because he never mentioned it to drum up any business).  So that comment is not valid if not laughable.  If you've been around long enough what's special about JPF is he's not just another mechanic that thinks he knows better.   He only did the mechanic thing as a late act in his career; he was a suit and tie organic chemist who happened to be good at working on Porsches.  If you've been around here long enough you have probably seen that every person that tried to take him deep on something came up dry.....every time.  His reasoning is always sound and adds up no matter how far you drill and tribology is no different.  If you keep reading and have a scientific mind (ie. you're not the type of person that enters a conversation with their mind already made up) I'm confident you will change your view.

 

If you ever saw what goes on at the top of every Fortune 500 company I can promise you they are driven by bean counting and marketing.  To think otherwise is either naïve or maybe you have never worked for one of these companies.

 

Happy Memorial Day weekend

[JFP in PA]

23 hours ago, lkchris said:

I believe you're misinformed (actually misinforming) on this.

 

As you surely know, the major German manufacturers all publish motor oil specifications which oil manufacturers must prove they meet.  It's a formal process.    Of course ACEA specifications are included.  The fact is, any motor oil that meets the Porsche spec will be a full synthetic and meet a viscosity requirement.

 

I once researched Mobil 1 products and learned that the cold pour points of 0W, 5W, and 10W versions were exactly the same.  That's all that's of much importance regarding the W number in a viscosity specification, that is cold start ability. I'd not spend a nanosecond wondering which I should choose.  The warmed up running number provides few realistic choices as regards 986 and these of course will be either 30, 40, or 50.  (BMW sometimes likes 60)  Again, if the product meets A40 the viscosity will be usable.  986 engines are a little older obviously, but in 2021 Toyota for some models specifies a 0W-16 motor oil and you can take to the bank it isn't going to fail in Death Valley.  Neither they nor any other other manufacturer are blatantly or otherwise attempting to have your motor wear out prematurely--that's grassy knoll conspiracy mongering devoid of intelligence or interest.

 

Experience indicates that it is typical self promotion felt needed by mechanics to dismiss factory engineering, in this case motor oil specifications.  Typically, as again here, without technical supporting detail.  I suspect it's especially ego satisfying and impressive to novices to recommend exotic things like Joe Gibbs oil.  My response is if any of you are petroleum engineers, you'd have a better job.  To blame bean counters or marketers is again typical nonsense.

 

PS:  ok, this is Porsche and we can all have lots of fun.  If yours is a track day only vehicle, have fun using an exotic oil ... in fact have fun using it in a daily driver.  The statement that A40 is all you need to know is accurate for most driving conditions and probably Porsche has set you free to do what you want for racing, as it doesn't accept responsibility for that in any event.

 

PPS:  these comments strictly about motor oil, other contributions on mechanical issues long appreciated.

 

Please feel free to continue to drink the Kool Aid brought to you by the same superb engineering staff that not only created the A40 marketing spec, but has also brought the market such engineering masterpieces as CIS fuel injection, IMS failures, M97 and 9A1 bore scoring, and other mechanical wonders to behold.

 

There was a time, back before Exxon bought Mobil, when Mobil 1 products were quality products, but that time is long gone.  Over the intervening years, Exxon has reduced the Mobil 1 product line to a shadow of what it once was as the direct result of the bean counters cost concerns of using higher group base polymer types, several times even losing the ACEA rating that the German automotive industry adheres to as members of the ACEA technical consortium.  And one of the most problematic products is their vaunted 0W-40 oil.  Independent UOA analysis has shown that this once excellent product not only has very little quality anti wear additives such as ZDDP when virgin, but can be also reduced to the equivalent of a 0W-15 product in less than 2,500 mile in a soccer mom’s Cadillac.  The Joe Gibbs oil you describe as “exotic”, but can found in such mundane outlets like Amazon, has demonstrated UOA’s with higher ZDDP levels after 6,000 miles of mixed street/track use than any Mobil 1 product ever had when still a virgin product still in the bottle, 60-75% TBN values at the same mileage where your A40 Mobil 1 product demonstrated 25-30% TBN, indication of the viscosity control and anti wear additives packages being nearly dead at less than 3,000 miles, and the oil being way beyond the industry accepted TBN level where the oil should be changed (50% TBN). And this is an A40 rated oil Porsche recommends you run for 12,000 to 15,000 miles between changes.

 

At the end of the day, feel free to use whatever oil you want in your car; it is your car and your money, and you are the only one that needs to worry about the consequences of your choices.  You may want to continue to blindly follow factory recommendations that are more based upon marketing and accounting considerations than engineering, but when people ask my opinions, I try to give them the benefits of my over 40 years of successfully building and racing the Porsche engines, what I and my team have collectively seen operating a very successful independent performance oriented shop, and the the data we collected, which by-the-by includes a database of literally thousands of UOA’s  on many brands and types of oils.  So while you call that “self promotion”, I and others might see my comments for what they really are: Accumulated hard earned experience and data based knowledge.

[mikefocke]

I've communicated with JFP publicly and privately on Boxster subjects for probably 15 years and I have never seen a single sign of his attempting to make a penny. I know he had a shop, knew the general location but never knew even the name of the shop or its exact location. Which is startling in this day and age of self promotion. He offers insights freely and for free. How he manages to avoid burnout is well beyond my understanding.