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YOUR RESEARCH996 Oil
Leading reported evidence
Run 2-3 degrees cooler
Performed · outcome unconfirmed
No successful repair reported for this finding.
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0
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Performed · outcome unconfirmed
I use Red Line as recommended by my mechanic, and noticed right away that the engine ran 2-3 degrees cooler.
Leading evidence: 'Run 2-3 degrees cooler' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'best and easiest i.e' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Check numbers (particularly hths' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed
The Mobil1 5W-40 on the shelf today is also API-SM graded, which means it also has the lower levels of the anti-wear additives that all SM-graded oils do, versus the SH oils the 996 engines were designed for and tested on.
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Performed · outcome unconfirmed
(I use Mobil1 0-40 to top up, as and when required.)
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0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
I use Red Line as recommended by my mechanic, and noticed right away that the engine ran 2-3 degrees cooler.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
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6SpeedOnline: 1 discussions
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Generation: 20261026T222516Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Since my car's out of warranty I can use whatever I think is best, which is a blend of:
5 quarts Mobil1 0-40 (automotive oil), plus
4 quarts of Mobil1 Racing 4T 10-40 (4-stroke motorcycle oil)
(I use Mobil1 0-40 to top up, as and when required.)
This blend gets very close to simulating the Mobil1 API SH-grade oils as specified by Porsche for the early 2000's 996. Today's API-SM graded oils have lower amounts of anti-wear additives. Check out the dissertation on engine oils on the LN engineering website (
http://lnengineering.com/oil.html
); this is what I consulted before embarking on the recipe I'm now using.
Mobil 1 5-40. Been leaning toward Castrol Syntec or Motul...same grade. Really depends on where you live with the temps you get. Viscosity is a science and the 1st number means something at cold start and the last numbers mean something with the operating temperature. Best thing to do is change your oil often say every 3-5K miles and drive the car the way its meant.
My mechanic is the crew chief of one of the GT3 teams.
He recommended Liqui Moly
http://www.liqui-moly.de/liquimoly/p...id/e_1360.html
It's made in Germany and retains the anti-wear additives.
I've been using Mobil1 0-40 since I got the C4S Cab. but I'm seriously thinking about changing to Royal Purple since a friend of mine swears by it which he uses in his Benz. Another 6speeder uses this Royal Purple blend for his 996... 8qts of 10w40 + 2qts of 20w50
Quote:
Yep, seriously. At least with Mobil 1. The LN Engineering article I linked in my original post goes into the gory details, but the short version is that the Mobil 1 formulation available today meets only API SM spec, which has lower amounts of certain key inorganic anti-wear additives than the API SH spec Mobil 1 that was "off the shelf" when the 996s were developed and sold new by Porsche. The change in API spec was done to prolong catalytic converter life (should any oil leak past the piston rings, the inorganic wear additives accumulate on the cats, slowly deactivating them), but at the expense of high-temperature film stability and wear prevention.
The blend I use takes advantage of the fact that the Mobil 1 4-stroke motorcycle racing oil has very high levels of the inorganic wear additives essential for high-temperature, high shear part protection--even higher than the SH-spec car oil. The resulting blend is very close to a 5W-40 SH spec Mobil 1 which is the original oil specified by Porsche.
Plus...I'm a chemical engineer by training, working in the oil industry. Making custom oil blends is *fun*
So next time I change my oil, I should switch from my usual Mobil1 0w-40 to Mobil1 5w-40 since it has
"very high levels of the inorganic wear additives essential for high-temperature, high shear part protection"
?
Quote:
The Mobil1 5W-40 on the shelf today is also API-SM graded, which means it also has the lower levels of the anti-wear additives that all SM-graded oils do, versus the SH oils the 996 engines were designed for and tested on.
The key in the blend I'm using is the use of the Mobil1 4T 10W-40 4-stroke motorcycle racing oil...it's not SM graded and has much higher levels of the anti-wear additives. Blending the 4T with SM graded Mobil1 0W-40 gives a near 5W-40 SH graded Mobil1 (which you can no longer buy).
50/50 is fine and is what LN engineering's article on oil suggests. I blend 5 qts 0W40 regular Mobil1 and 4 qts 10W40 of the Mobil1 4T racing since my 996 takes 9 quarts on an oil change.
My first post in this thread gives more details and link to LN's article,
Castrol Syntec 5W40 is SL rated. Should be better than the Turbo Diesel 5W40 Mobil 1. Right? Seems like probably the best and easiest i.e. no mixing, and you can buy it anywhere. Thoughts? Agree? Disagree strongly?
Oil formulas and standards change all the time. That's why all of the 0W40 guys who blindly follow the recommendations from 10 years ago may want to consider switching to a 2010 spec.
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+1 on not blindly following anything...but, in this case, I'm not. Oil formulations have to balance a lot of performance factors. The SH to SM spec change traded decreased high-temperature wear resistance for increased cat converter life in cars with significant oil consumption. Our *friends* at the EPA in DC care about emissions, not engine reliability. Cats are cheap; engine rebuilds are not. Knowing this and the nature of current oils is what drove my decision to go the route I have.
As for the Syntec SL 5W40...that's another possibility. Read the LN article, check the numbers (particularly HTHS test results IMHO). Like I said before, I like messing about with oil blending but I fully understand that many others don't (like She Who Must Be Obeyed
, when I make a mess of the garage).
I went for Valvoline Racing VR1 5W50 (only for Europe)
In Bob's the oil guy there's a pile of info
C. Navarro has a fantastic exposition in his web too.
You should never blend different oils. They can have a chemical reaction as they are synthetics and they do not mix. I have been reading about that for many years. Your P-car manual should let you know what oil to use at what temps. I prefer the "old" mobile 1 that still has ZDDP. The High mileage one. The EPA will not give the starburst, because they say ZDDP clogs cats, but the wear protection is great. I also love Royal Purple, best wear protection, but it breaks down a bit faster over time.
wow, very cool. I haven't visited 6speed for some time, and I'm taking a look around and here we are in the midst of the continuing and neverending OIL WARS. Hoo-rah. Semper Fi. Let's rock and roll like we did last summer, baby. ok, enough of that. Red Line 10-40, my friends. There, I'm in, locked and loaded. Burke, what do you need in your car at all times? Right, a spare Red Line bottle and a Springfield EMP.
Well, I was off work for a month from an injury about 2 years ago and studied oils the entire month. It is confusing, mostly because the EPA is jerking oil companies around. Lots of false data out there too. I have seen hundreds of tests and oil analysis data on uncountable numbers of oils. Many companies make deceiving claims, but as I compiled all the data from tons of hours of study, I switched from my beloved Royal Purple, to Mobil 1 High mileage. I do think that Royal Purple is the best oil for cars that don't sit around for long, but I decided to change after all that I learned. I own many cars that sit around most of the time, so I decided to pick an oil that has been tested and proven effective, and has a bit longer life. I wrote tons of info on here with links to everything about 2 years ago. The discussion went on for over 50 pages. It is confusing, but I feel confident with my choice. As far as weight goes, use what the manufacturer recommends for your climate. I have a different weight oil for 5 cars... Crazy. I really love Royal Purple though, because when I rebuilt my 300ZXTT with 140K miles on it, My machine shop guru said that he had never seen an engine with so little wear with that mileage. I had no brown stains on anything. The metal parts were all super smooth and shiny. My machine guy was confused why I was doing a rebuild, but I just needed a stronger bottom end so I can push my RWHP to close to 600. The stock internals are only good for about 500-550HP. That really made me a believer in Royal Purple. That car only holds 4 quarts with a larger oil cooler. Under 4 quarts stock, so that oil was working hard and staying really hot in Tucson, AZ. Virtually no wear. I'm sure if you want more info, search past posts. Tons of info on here with real studies and real tests. The discussion was on the 996TT forum.
oil wars are great. lots of information out there.
I use Red Line as recommended by my mechanic, and noticed right away that the engine ran 2-3 degrees cooler. Also ok for your cats, should not burn them out.
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