Oil question, sorry in advance, Im confused, DT40 or DI40??

So Ive read that the DT40 was developed specifically for the M96, but also read that DI40 is better, from seemingly knowledgeable people on the subject! So which is it?!?! My vehicle is a 2000 911 C4 manual with 163k miles. Engine rebuilt at 137k. I live in SC, I drive it hard, daily driver, but I dont track it.

Here you go. Driven DI40 / DT40 & pca Video - Rennlist - Porsche Discussion Forums https://share.google/987yaol0BuXRYr6Wh

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If you street drive the car, DT40 is great. If you have mixed use including track use, DI40 (or DI50 if your oil temps are sustained above 225F or peak 240F) is what you should run. https://lnengineering.com/products/driven-racing-oils/

Ok Im going with DT40, thank you!!!!!!

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Might help to see what Porsche's recommendation on oil viscosity currently is for our 996.1 & 996.2. The "50" is the important thing to note, regardless of brand type, especially in a southern climate going into summer, driving it hard.

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I know, and Ive seen that. The fact that Porsche recommends a 50 weight and an oil that was designed for the M96 is a 40 weight is hard to square. I guess Im back to square one. I dont know what to run.

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Newer to 996 ownership so I�m sure I�m missing something obvious, but just curious where you heard that the Driven 40 weight oils were designed for the M96? Going on the Driven website, I didn�t see any specific mention of Porsche other than �DI40 has an active following in the Porsche community�. DT40 page just says its used for German, Italian, British sports cars and Chrysler 6.4L hemis, as well as for European turbocharged engines. I have definitely heard about the many positive benefits of the oil in our engines, but was just curious about the �designed for� comment as would think it would be specifically called out on the website. Thanks!

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Lake Speed who was the tribologist at Driven worked with Charles Navarro and Jake Raby to develop DT oil for the M96. Later the DI oil was developed which many of us prefer. Both are excellent high moly, high viscosity oils. DI can be run on both the street amd track, whereas DT is for the street. Watch the video I attached early on in the thread. It will fill you in.

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Thanks for that. Is there any reason not to run DI on a street use car? Is it overkill and extra $$$? I don�t usually drive my car that hard but once in a while it gets the old Italian tune up.

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DI is more expensive would be the only downside. I run DI50 on both street and track. If I didnt track my car I would still run DI. FwIW, if you live in a cold weather town amd want to drive your car during the winter, you may want to consider running DI40 in the cold weather months and then switch to DI50 in the warm weather months. DI50 is higher viscosity than DI40 and will improve the oil pressure.

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The Driven website leaves much to be desired. I have brought this up to them on several occasions. However, if you do contact Driven regarding Porsche applications, they just forward those inquires to us as they don't have any European specialists on their support staff. I myself deal directly with the person in charge of formulations. Jake and I did the testing for Driven in Porsche engines way back in the day. In subsequent years, Driven purchased a Boxster and did extensive OTR testing on that platform to back up our results. You Tube Although Lake may not be at Driven any longer, he still drives a Boxster. LN's in fact, with a 3.8 with plasma sprayed bores that has been on the road since 2019. All this aside, just look at the used oil analysis results shared by other forum members with their use of DT40. There really isn't any other reason to use any other oil in your street driven Boxster, Cayman, or 911.

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Got it, thank you for this. Guess I have more to catch up on!

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Thanks, remember watching that a while ago but will rewatch - must have missed some of it.

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Thank you so much for the input. One more question, just to confirm, and I promise Ill drop it LOL. Considering 1) I live in South Carolina (its hot), my car has 163k miles, 2) it was rebuilt 25k miles ago which included honing and ridge-reaning the cylinders (which I assume might increase internal tolerances a little bit?) and 3) I tend to try to drive hard on the street (but not track), do you think it would make sense for me to run a 50 weight oil?

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Was this 'rebuild' on oem @163k miles Porsche lokasil cylinders, or on previously built sleeved niksil or steel cylinders...?

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Im not sure, the rebuild was done at 137k in 2019 at a shop in Thousand Oaks California. I have the paperwork but there is no mention of any sleeves?

Correction, the shop was in Pasadena and it was in 2018. Paperwork shows new piston rings, rod bearings, main bearings, etc, etc...$15,000+

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Oh no,, I'm sure Charles , just like me, enjoys answering the same questions over and over and over for decades, as these cars owners change hands, even if the answers to the questions change a little bit over the years...( j/k ) One interesting comment you made about the honing and ridge reaming on your engine... Ridge Reaming is never needed on Lokasil cylinders due to the extreme harness and wear resistance...Thier failure mode is scoring or ovaling....and the "Honing Process" is very very specialized and even though Kolbenschmit ( the Lokasil invention company ) has a process for this, I have never seen anyone who successfully refinishes these cylinders using the process....Hartech had some limited sucess doing this but in 2019 7 years ago went to replacing the full cylinders with Nikasil plated ......If this statement is indeed correct, I would love to know the "full detailed technical story" behind this " rebuild" .. PS : I'd love for you to do a Blow-by test on this engine to see how well these cylinders are actually sealing...

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Yep, I think the " Ridge Reaming and Honing" is just a "figure of speech " carried over from the Old Days since this was an old bussiness... In actuality they probably brushed the cylinders with a dingleberry bush and put in some new rings .... and they put in all new everthing else.. We did some rebuilds like this at Tom Williams Porsche back in the day 2004-2010 not quite that much cost because back then we could get a "AT" engine from Porsche that was completly new, even had oil in it, for $6800 ... I would still like to know the results of the Blow-by test on that engine...

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I was just reading your thread on the blow by test, Ill have to do that one day. So you think this particular engine in this southern climate, especially in summer, would probably like the 50 weight oil over the DT40 or DI40?

I'm in DC, so mid-atlantic where we get some colder winters and I have ran 5w-50 for years with great results. Have a bunch of UOA from speediagnitix showing it works and works well. Remember that the 50 number is the viscosity when the oil is hot so the climate doesn't really matter that much. Once the motor and oil are up to temp, they are up to temp be that in February or August. You just get more headroom with respect to oil performance once you really push the motor. Modern synthetic oils flow very well, even at cold temperatures.

I found this comment on Reddit from LN engineering.... FR50 no longer available and according to Driven website, the replacements are DT50 (10w-50) or HP-X 5w-50. Im currently leaning towards the DT50.

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Skip, you beat me to it. I saw ridge reamer and immediately pictured them also knurling the piston skirts :-) I sure hope they didn't "hone" the cylinders either. Needless to say, I have lots more questions.

We recommend Driven DI50 or Motul 300V 10W-60 with ~5k mile intervals for our street engines. It’s cheap insurance against rod bearing issues from oil starvation. And we have hundreds of UOAs and data logger traces showing this to be the best protection for our customer's engines.

I feel bad for OP being taken out behind the wood shed for repeating what he was told about his rebuild process, LOL. Atleast the right people are in here to set the record straight on both oil and the appropriate processes for major overhaul on an M96. Anyhow, for OP� however it was rebuilt, it�s been 25k miles and your biggest concern to date is oil weight. You should do a blow by test now, then refill with a 50 weight as recommended here annd do another blow by test after 50 miles. Then you�ll know your engine rebuild is holding up just fine and you�ll have a data point between the two oil weights as well! Once you have a manometer and a modded oil cap in hand a blow by test only takes 5 minutes, unless you include the spirited drive to get it warmed up. That could take all day�

Well I had studied this document before I bought the car and knew that it hadnt been resleeved. But other than that, it looked like a thorough rebuild. So I figured if I could get the car for cheap, it was worth the gamble. And I did. $17k for a Manual coupe original paint rust free Millenium edition with 19k on an engine rebuild and a stack of service records going back 2 decades from that same shop, wasnt bad. Since then Ive been resigned to the fact that I like this car enough that I want to keep it forever and would be willing to spend 20k on an engine rebuild if I have to. If I can get another 20k-25k out of this engine, Ill be happy. Even if I have to do a rebuild, I wouldnt be that much upside down if I did decide to sell it.

So now maybe the question has evolved from which type of 40 wt, to 40 vs 50, now to 50 vs 60 weight! I guess I just need to do a blow by test to see where Im at.

Everyone has an opinion, here's mine. Agreed to get the blow-by tested as a baseline. I think the best way to determine what oil to use is the Used Oil Analysis. But this is a long process. If you test every six months, you'll know pretty quickly if one oil is doing better than another. Once you have a stable base, you can back off testing to once a year. To be fair, both these oils are excellent at 40W. 50W and above is for heavy use conditions, track or hot atmosphere. The difference in engine life between them for a street driver is likely nothing.

To be technically accurate about oil viscosity recommendation I would need to know the coldest your oil will see, the hottest your oil will see, your climate location, your driving style, your vehicles usage pattern , and most important, the exact oil pressure measured at the heads at exactly 4k RPM with 40 weight oil at exactly 90C oil temperature.. Recommending an oil weight without all this data is like a Doctor giving a Dietary Plan to someone without knowing their height, weight, age, physical health, life-style , and expected goals... Sure you can give general recommendations, but it seems easy for Porsche owners to take them out of context, or to misunderstand the scenario around the recommendation....I guess that's why there is endless threads on the subject.. I think the most important thing to know about protecting the M96/7 engines from oil starvation is the higher viscosity oils will slow down the flow of oil out of the Sump. This leaves more oil in the Sump so that air is not picked up by the oil pump... This is most important when doing high-G-force maneuvers ...( one of the biggest difference between the design of the oiling system of the Mezger GT3 and the M96/7 is how much/fast oil is returned to the Sump from the heads...GT3 has 4 pick-ups at each corner of the heads while M96/7 has only 2 at opposite corners of the head ) ...So the higher viscosity oil can help a lot in these curcumstances ..

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"my 2�" , don't make this more complicated than it is. We now know more about your 996 usage, engine condition, ambient conditions, & type driving. Blowby test would be interesting, just like knowing engine oil consumption, if there is any piston slap, etc, but imo not needed to choose the best oil for you. As we can probably guess what a full on blowby test results would probably be. At the least, Use any quality 0/5/10/15/20w-50 oil. 50 being the important number. More than likely, all on this thread will agree thats the best oil for a hard driven, hot climate, high miles, m96 996. Especially with the new info on your honed ridge reamer lokasil m96 build. I do believe the rebuild shop did exactly what they wrote on the receipt. To help anyone choose a m96 oil,,, Best to have a higher content of Zinc & Phosphorous anti wear additives, and some moly for lokasil cylinder wall to piston protection. Not a lot of oils have lots of moly so get a can of Cera-Tec additive and dump in half a bottle to those oils that have low moly specs. Not trying to take away anything from Driven oils, they're a great oil with all the needed components, just at a premium cost of more than double many other appropriate m96 quality oils. jmho

Walmart has Mobil 1 15w-50 for a really low price.

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Anyone compared VOAs between that and the Porsche classic 996 oil?

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As far as the temps go, I live in SC, I drive it hard and I drive it everyday. I dont track the car but I basically drive it as hard as I can on the street. Im not sure if this is specific enough but my oil pressure gauge is over 4 at 4k at operating temp with the 40 weight oil Ive been running (currently Liqui Moly).

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No idea, but based off this VOA for M1 , I'd say it's a good oil to use if you add in some Ceratec.

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Understood, but in this case Im basically trying to eke out as many miles as I can out of this engine, so I have to figure there is an optimal oil

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if i owned your car and its history, the first thing I would do is call the shop that did the partial rebuild to understand exactly what the did to it. Then i would take an oil sanpke and send it in to Lake Speed ar Speediagnostix to establish a baseline understanding. Then I would drop the sump to see whats in it, cut open the oil filter to see whats in it, then scope the bores to see what you have. Then I would fill it up with either DT50 or DI50 and perform a blow by test and then live happily ever after.

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Yes I have actually done all those things to a degree. I couldnt get much info from the shop on the rebuild because it was 8 years ago and they changed their system since then. I sent the car directly to my Porsche Indy shop right after I bought it over a year ago. (I actually consulted with them before I bought it.) I had them take an oil sample for a UOA, they use Oil Analyzers, and there were no abnormal levels of anything in that sample. I had them do a borescope at that first visit and they said it looked fine. At one of the following oil changes, I cut a filter open and found green/brown bits and along with the code I was getting, figured out one of my cam adjusters was deteriorating and wasnt fully adjusting, so I had the shop replace it. I have not noticed any significant oil consumption or signs of it like sooty tailpipes or any smoke whatsoever. I agree Ive basically come to the conclusion I should probably be running at least a 50 weight oil considering mileage of engine on original cylinders and the climate where I live. Although, Im not real sure that the results of a blowby test will cause me to do anything differently than I will be doing anyway? And I do plan on living happily ever after regardless! Thanks to all for the input!

Here you go. From @Porschetech3 Quickest and best test for engine health " case in point" - Rennlist - Porsche Discussion Forums https://share.google/poZ1ZqsfFqyeLwqsW Engine health "blow-by test" - Rennlist - Porsche Discussion Forums https://share.google/Vq7QpmueuPoUxpcW7

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OK. So past the point of knowing your blowby and doing UOA, you need to instrument your engine to understand the aeration your engine produces, as discussed in the Oil Pressure Instability thread, https://rennlist.com/forums/996-foru...ility-124.html . You can use this method to validate that the heaviness of the oil is sufficient for your radical driving. No more guessing. I can help with the data when you get it.

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If you "fancy" a rebuild, look at Slakker in Oklahoma City. Call or write to Brandon Clark, and ask a bazillion questions. He is gracious enough to answer all, even the "dumb" ones (I had a few....). Cost is commensurate with excellent warrantied results, 100,000 miles of reliability, and the 996 p-warts & failure points eliminated. Slakker has multiple "Adds" that increase power and cost. so you can pick and choose, just like on a menu. Simple. Go Look: https://rennlist.com/forums/996-foru...today-844.html , post #12656 & post 12671 for some photos. Other than that, I wanted to walk my pet-peeve, but found that my pet-phrase had run off with the leash. YMMV

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Well, as long as this is another oil thread.... So, while you recommend those 2 oils, why not also recommend VR1 20-50 and Mobil1 racing 0-50...? I'm Using VR1 20-50 synthetic now in my 996 engines and like it. OP seems to always stay high even when as hot as it will get in summer s FL weather in spirited drives. I've used M1 racing 20-50 a lot in my high strung boosted engines very successfully, ya its as expensive as the DI50 and maybe even harder to get. Won't find M1 0-50 or VR1 20-50 synthetic at Wallymart, ...These are both a superior oil imo. M1 racing 0-50 might be a great track oil if not going with a 60 weight. Valvoline VR1 20-50 syn seems to have a very similar additive package as DI50, maybe better(?), as does MI racing, and M1 racing has the most moly of any oil on the chart you posted below. Both the above oils have as good or better astm/cst properties at all temps as the DI50 and the Motul 50. I like the below chart, thanks for posting it. I've checked values on the manufacturer sites and chart values seem to be all correct, at least for the values they list.

I did find at least one inconsistency. These two highlighted numbers do not jive. One of them has to be wrong. As I've said before, the specs on paper are one thing. The info on the chart is valuable but how it performs is completely different and arguably more important.

Jeez, Driven gets so much attention on this forum, no doubt due to its sponsor (and former sponsor Jake Ruby) marketing it so heavily on rennlist over the years. Not dismissing their overall efforts, but certainly a conflict of interest. The Driven website indicates it was developed for NASCAR, not sure if any teams use it. If you search rennlist, you’ll find a quote from Jake indicating he recommends several different oils, e.g., Motul, Redline, as well as Driven, and you should ask your engine builder what they recommend. Driven does not publish the same specs other oil producers do, so difficult to research. Ultimately, if LN and Flat 6 want to properly demonstrate the superiority of Driven, they should publish used oil analyses of M96 engines comparing different oils under identical conditions after extended use. FWIW, I’ve used exclusively Motul X-Cess 5W-40 for three HPDEs (yes, should have used 5W-50!) and 20K DD miles on a rebuilt engine with virtually no drop in UOA values between annual changes. FYI, Motul now sells Power, a mid step between V300 and Xcess. There’s a thread from several years ago discussing 5W-40, -50, and 10w-60. A Motul representative indicated 10w-60 should not be used in the M96 engines. Check out https://bobistheoilguy.com ! Lots of independent information.

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Hey man, i am all ears if you can pinpoint the best oil for an M96 engine. In the meantime, i will continue to encourage the M96 industry professionals who put their reputations and businesses on the line every time they open their mouth or reply to a question. No question they have a vested interest. So do we as 996 owners.

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Lake has said the exact same thing. And Lake has no vested interest in Driven or any other oil company. And he is an owner of a Porsche Boxster.

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As is so commonly posted, do a search. There are literally dozens of threads and even more posts with UOAs for Driven DT40 compared to most all A40 approved oils. The proof is in the pudding. I have also publicly posted that MIllers Nano is just as good as DT40. I have personally run it vs DT40. And yes, I am biased. Jack Ruby and I were intimately involved in the development of DT40, DT50, and DI40. I'm also still working closely with Driven (waiting for a call back now from Bill at Driven). And do I technically make money on selling oil. Not really. Free shipping and credit card fees leaves us making next to nothing. It's sold because we believe in the product, but do what you want to do. There are other choices, like LM+Ceratec.

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We recommend the heavier weight oils because they cover all of the scenarios. Even a street only driver with an original engine that burns 1L every 1000 miles, is due to add a liter, but finds himself in some twisted roads and decides to romp on it for the first time in years. VR1 20W-50 full synthetic is on our approved list specifically because it can be purchased locally. The challenge is ensuring people buy the synthetic version and not the conventional version, which we've seen some very poor UOA's from. M1 racing's low HTHS rating is concerning to me though we do have a customer running their 0W60 with success. Both numbers are based on M1's published data. I don't have a good explanation for why their HTHS is so low.

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........and Budget $$$$ and Frugalness ..... No 60 weight oil full synthetic is on the shelf at Wally World...

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Wally World for the win. Not sure why I continue to waste my time trying...

What's the point of dt40 if you need x-60 or at least dt50? What advantage is 40wt if 50wt or 60wt saves motors?

"Application dictates chemistry" Lake Speed

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Street versus track. That's the short answer.

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Because that's what we DO !!! Doctors " Practice " Medicine.... We "Try" to fix all the cars........

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Yes, agree those are the numbers I've seen. And the posted HTHS is the correct number as published by M1. Not being an oil engineer can't say this is 100% accurate, buts its whats been said about M1 racing oils for years now. Supposedly the large quantity of VII's required to get the large 0w50 viscosity spread leads to a large amount of temporary viscosity loss when the oil is sheared at the extreme high temp of the HTHS rating of 300� F. In reality no engine should be run even close to 300� oil temp, so imho its almost irrelevant compared to the 280� ATSM rating. And the M1_0-50 racing oil posted ATSM rating at 280� is pretty dang good at 9.8, better than Driven 50's 8.1. Whats max engine oil temp you recommend on your 996 builds...? JMO

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The HTHS number at 300F is not irrelevant.. .. The actual engine oil temperature at the ROD Bearings can be much higher than what you see on the " gauge" because the gauge is a "average" of all the oil in the system and quite a few people are measuring oil temp at the Head which is after the oil cooler and still seeing about 270F "after the oil cooler"...... Sure if you can keep the oil temp lower it is much much better because Heat and Friction is Engine Enemy #1 !!! ( and dirt ) The HTHS number is how well the oil " maintains" its viscosity under high temp and high stress .. It is common to see even high quality race oils loose 3 points of cst @100C in just a few hundred miles of track time... ( one weekend)...

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Wouldn�t a higher HTHS oil, with better film strength under high temperature and load, reduce the chances of dropping into boundary lubrication and help mitigate bore scoring?

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Again, depends on operating temperature, as I stated above. Higher viscosity on a street driven engine is a band aid. More is not always better.

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Don't misunderstand my post or take bits out of context... Its comparative to the M1_0-50- ATMS @ 280�. Which in my opinion, once engine shows that high a oil temp, its time to back it back down and let things cools off unless you're in the heat of battle last lap and about to take 1st place on a pass. Checkered flag is in sight, and don't care if engine needs a rebuild after the race... Supposedly, iirr, M1 0-50 racing starts to fall off the cliff around 290 then drops 4 points quick once it reaches 300�F. But keep in mind it still is similar HTHS of DT40 at those extreme HTHS 300� temps that most will never see ever, if they know whats good for them... "Mobil 1 racing oils are the official motor oil of NASCAR and are used by over 50% of teams in the top three national touring series, providing extreme engine protection and performance. These high-performance, fully synthetic oils are engineered to reduce friction and withstand extreme racing temperatures." M1 racing oil engineers are no fools, You'd think if there was a problem with the HTHS in M1 racing oils all of Nascar would drop them like a burnt valve.

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Not necessarily. There is a viscosity sweet spot; more is not always better . Film thickness rises with viscosity but the flow rate also drops as viscosity rises. So increasing viscosity will give you diminishing returns once you are safely separated (full film) while continuously penalizing flow. You are assuming a higher HTHS automatically always equals better protection....but your mental model is not correct. A shear-stable 40 weight is the sweet spot of flow vs film strength for this engine. The only case it might make sense to move up to a 50 weight is sustained high oil temps where the 40 weight is shearing down or thinning excessively.

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Honest question - why does Porsche Classic sell 50 weight for the 996 and does anyone know who makes that oil for them?

If 40w was the sweet spot, we wouldn�t be seeing this many engines, street and track, exceed its safety margin�and fail.

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Im wondering if its just the Mobil 1 15w-50 in a cool looking can. EDIT: that wouldnt be right as the "Porsche" oil is a 5w-50

Sooooo..... DI50 or DT50 for a 163k mile, ragged out, daily driven and thrashed M96??

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Not all 40 weight oils are the same and there are variables you aren't controlling for in this generalized statement. When I see you saying things like DI40 voids your warranty and there are "conflicting agendas" it makes me wonder what your agenda is. I recently stripped down one of my engines at 135K miles that ran DI40 almost all its life since around the time it first came out. The engine looked brand new. The crank, camshafts had no wear. Things like the rod bearings looked like they had only been run a few thousand miles. I had bought new upper and lower shells to replace them with like just about every other wear item in the engine but after seeing them I skipped it. I showed them to a friend who is a dealer mechanic and has rebuilt hundreds if not thousands of these engines -- his response was they looked about the best he has ever seen. I don't know what you think is outdated but what you are saying goes against what we have known about hydrodynamics for over a hundred years and still holds true today. When you're riding the Stribeck curve once you reach full-film hydrodynamic lubrication friction and wear don't improve, they get worse. What you are advocating is that being the farthest to the right of the Stribeck curve is optimal, but this is not right. You want to stay in the sweet spot on the plateau.

After reading this from the Porsche site about its Classic oil for the 996, Im LESS inclined to think its the right oil for ANY M96. LINK For a few reasons. 1) In the first paragraph, it says its suitable for the Turbo engines also. But the M96 seems to have a lot of issues that the Mezger Turbo does not, like bore-scoring. So I would think the M96 would require some things in its oil that a Mezger does not. How can one oil be best for these 2 very different engines? 2) In the second paragraph, it says the purpose of the Classic oils is to mimic the oil that was available at the time the M96 was developed. Is it not true that the oil that was recommended and used back than may have had something to do with the wear issues that M96s are known for? Why would we want the old tech oil when the M96 has issues somewhat attributable to that oil?? We have the benefit of 2.5 decades of hindsight and gained knowledge that tell us the weak points of the internals of the M96 that nobody knew then. Doesnt that knowledge tell us that these engines require something extra in their oil, regardless of how its driven? And finally, it says its for the "usual use" here and also mentions elsewhere that the oil was for cars that arent driven regularly. What about for daily drivers??? That is all a bit bizarre to me. Maybe theres a good axplanation, but it escapes me right now.

My agenda is simple—I want to see less of this: https://www.facebook.com/share/r/1BMr51MwVy/?mibextid=wwXIfr There is no warning light that says: You are now exceeding the safety margin of your oil—please stop your car and upgrade immediately. And in the real world, we continue to see excellent UOAs from owners following our oil recommendations. And I have yet to hear from anyone who moved from DT40 to DI50 that did not see equal or better results.

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Unofficially it's now ROWE.

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Its a very complex topic on application and chemistry coupled with procedures. I have had a 23 year test case for the M96. As an example, my 2002 996 has 68k miles, half of which are 110+ track days since 2004 and driving too and from the track, and the other half is tooling around town since 2002 in the midwest 4 season climates. I have no borescoring and very good oil tests. The question is why? To add more detail, i ran Mobil 1 0w40 from 2002 thru ~2008 and then moved to Millers Nano 5w40 until ~2021, then DI40 until 2023 and then DI50 since. So why no bore scoring or oil starvation/bearing problems on the track especially after all the years with Mobil 1 0w40, and then all the years with Millers 5w40? Yeah, i even run in the fastest run group and a good portion of that time on Hoosiers? Today its RE71RS. For sure, I have run a 2qt deep sump and Pprsche Motorsports AOS since the beginning of time, and now run the much better UAOS, so I always had between 10.5 qts of oil in the engine w/ the PMS AOS and now 12.5 qts with the UAOS. No question that this helped with lubrication and cooling. But there an interesting variable to the equation, which is the frequency of oil changes, which i have been maniacal about oil changes. I dont go to the track unless I have fresh oil. Nor does my oil sit in my engine for very long if I dont go to the track. To put it another way, the oil is always fresh and therefore it doesnt loose its lubrication qualities. Yep, i have over 110+ oil changes over 23 years. But if i didnt track the car, I would still change the oil 2x year. If I went 5k miles between oil changes I would break out into hives. Imho, frequency of oil changes is critical, and can make up for short commings in sub par oil chemistry like Mobil 1, or 40 vs 50 oil. While running 40w oil for so long hasn't necessarily hurt my engine with always keeping the oil fresh. But I do wish I ran Millers Nano 50 or DI50 instead of the 40W oils on the track. But at least I can do it now. Best advice I can give is to run the best high moly/viscosity oil you can afford and keep it fresh.

Quotes source post: 20555623

Yes. DI50. Change it. Then change it again in 1000 miles, or one month. Then change it at 6 month and send a sample in for UOA. Then another UOA in another 6 months. Then you will be able to know something about engine using this oil. Post results back here for further discussion.

Quotes source post: 20555867

Why DI over the DT? The DT has more Moly than the DI according to that VOA above. Isnt that what we want, more Moly? This is what started this whole conversation, the "I" vs the "T". Which do I want/need and why?

Quotes source post: 20555923

Somebody asked me already and I make the recommendation of DT40.

Quotes source post: 20554814

Interesting point, I agree. So, are you saying 270�F is OK normal 996 running oil temp...? How to measure that difference of incoming rod bearing oil vs the oil that flows out of bearing while lubricating the bearing would be quite the experiment.

I had always heard that at 290 on the oil gauge your M96 is toast.

Quotes source post: 20555923

DI40 and DI50 use a higher quality, more shear-stable viscosity modifier (LZ/Star 100cSt), which is designed to better resist viscosity loss under extreme shear. In other words, it holds up better when you need it the most.

Love me a good oil thread 😉 Quick question - DT 15w-50 seems to be more readily available (from forum sponsors) - but descriptions say for air cooled. 15w ok for our 996? Warm climate here in NC. Thanks much for so much good info

Unless your car is in death valley or on a track DT50 isn’t necessary dt40 is perfect on my 996

Quotes source post: 20556633

Not an issue and I'm on my second OCI with DI50 and many DT50 changes before that. Recent oil analysis looked great. Take a look at the graph of outside temp vs viscosity I posted above. Unless you're seeing temps in excess of 20 degrees celsius below freezing, which I suspect you don't in NC, a modern synthetic like DI50 will provide sufficient flow at start up. If you're closer to Canada, where it does actually get that cold, then different story. This old thinking might have held true for old non-synthetic oils but is not the case these days. FWIW, BWM specs 10w60 for their E46 and E90 M3 with their V8 motors. Every so often, mid summer, I'll be stuck in some really bad city traffic where you're just sitting there for extended periods of time creeping forward...you'd be surprised how quickly the motor will heat soak and the temps will get to 220F. Happy to have a 50 weight oil on those days. With 40, I remember seeing oil pressure drop to 1 or slightly less when at idle.

Quotes source post: 20557570

Completely different engine with different tolerances. Not relevant to this discussion of M9x.

I'm no tribologist and I know we are talking about the different Driven oil options, but for the OP's use case (aggressive street driving in hot weather), Valvoline VR1 Full Synthetic Racing Motor Oil SAE 20W-50 seems like a good option with high moly at half to a third of the price of Driven, Motul, Millers, and Redline options. Any reason not to use it? Do you get what you pay for?

Quotes source post: 20559106

Couldn't agree more, VR1 20-50 is a great oil with very similar additive package as Driven or better, and from the specs, better ATSM specs than all Driven 50's. Problem is, many go down to Wallymart and see VR1 20-50 Valvoline on the shelf and thinks its the oil I'm talking about. Its not, as Walmart does not sell VR1_20-50 FULL SYNTHETIC on the shelf . From what I've tried in the past, can't even order it from Wallymart. The oil sold at Walmart is the conventional oil VR-1 20-50 . I do not like how many vendors treat this distinction between VR-1 conventional oil (dino oil) and full synthetic oil VR1. Its like they play a shell game with the oils. On the Walmart site they do list VR 1 full syn , but do not sell it (not available for years now) and try to switch your cart or 'buy it now' to conventional VR1. Be careful as conventional oil VR 1 is not what we want at all. Other sites do similar switch and baits like this. VR1_20-50 FULL SYNTHETIC use to come in the black bottle, it has been changed recently to the same grey bottle the dino conventional oil VR1 comes in. Very confusing for most. Not sure why they did this, other than a marketing ploy, got to luv those bean counters. But on the bottles if you read it, they do specify either full syn or conventional oils. Thats the only way to tell the difference. So make sure to read the bottle. Best place to get VR1 full synthetic oil is right on the Valvoline site. No shell games there. Can get a 25% discount on 10 quarts for $85 free shipping (only comes in qt containers). As long as we're on the subject of other good oils, some have said Mobil 1_0-50 Racing oil is on the shelf at Walmart, IT IS NOT, ever. Its very expensive, similar to Driven. Sometimes you can order it from Walmart and get it shipped.

Quotes source post: 20559106

Im looking for a VOA of the VR1 synthetic 20w-50 to see exactly how much Moly it has in it, but I cant find one. Any idea?

Quotes source post: 20559556

Take a look at the grid on post #43. The column has Mo at the top.

As @allcool says, the best source for VR1 Full Synthetic 20W-50 is the Valvoline website. They have several coupon/discount schemes that get 10 quarts delivered for $82.85 on my last order in February. All the oil arguments are somewhat silly (to me) if you�re just driving your car around and enjoying it. Yeah, if you�re a racer there might be a difference but for normal, spirited use just pick one and stop obsessing over it. At least that�s my approach 😆

Quotes source post: 20559837

That may be true on a 50k mile engine, but mine has 163k, and has shown signs of some cylinder wear, so Im just trying to maximize its life. And so thats exactly what Im doing, Im picking one!

Quotes source post: 20559581

Sure is, I missed that, thanks

Quotes source post: 20560144

As you can see from spec sheet, all the needed components at the correct levels are formulated into VR1 20-50 syn, and are very similar levels to Driven DI50, along with as good or better specs for HTHS and ATMS. no need to add any extra moly to VR1 syn. But, more than likely the base oils used in VR1 20-50 syn probably are not the same as Driven. I'm not the oil expert so can't tell you Driven has higher quality base components like many claim. What we can see from the ATSM & HTHS grueling test specs for VR1, that no matter what its made with, it passes all the main oil certification tests as good or better than DI50 at 1/3 the cost.

Quotes source post: 20560176

Lake may have done a test on VR1. We will all have to take a look. I dont mind paying more for Driven DI50 because my oil tests are damn good. Same can be said for DI40 in my Audis. Huge improvement over Castrol Syntech in the tests. But at this stage, I am not willing to be a guinea pig for testing on VRI to save a couple of bucks. Instead, i would rather see what tests are out there and what they say. I am about to send two oil samples into Lake over the weekend for both my 996 (DI50) and Q7 (DI40), and will ask his opinion of VR1 for the M96.

Quotes source post: 20560250

Agreed. I'll let someone else be the guinea pig. I have been on a quest to find the best oil for my Porsches for decades. For many years Mobil 1 was the magic oil until they, like all oil producers, reduced Zddp. Next, I found Swepco and it is still at the top of my list. Now, Driven oils seem to have the most robust combination of Molybdenum, Zddp and other mystery ingredients. My used oil analysis reports have been great. That's all I want. Sticking with Driven DT40. If you want good engine oil with the best ingredients, it will cost you. You like Maker's Mark? Ante up.

Quotes source post: 20560176

I get the impression from watching Lake on Motor Oil Geek YouTube channel that additive packages are not created equally. There's four main companies that make additives for engine oil. They'd all have their own formulation on making Mo. So having the same level probably isn't going to be the same effect? Viscosity Improvers would also be different and suffer from different breakdown rates I suspect.

Quotes source post: 20561105

Ya, could be correct... Maybe one of our resident oil experts will chime in. Like said above, just looking at oils spec sheets that both oils pass with great numbers that are very similar. Not sure how they actually get there or if that even maters.

Quotes source post: 20547474

The post above should be the last post in this thread.

Quotes source post: 20561848

Yes. I alluded to this previously. You can't estimate an oil's performance simply by its data sheet. Not all additive packages or their subcomponents are created equal - same goes with base stocks. I'm not hung up on base stock either. Some of the best used oil analysis reports I've seen over the years have come from oils made with group I from Pennsylvania.

Quotes source post: 20547450

i spoke to Jake Rabey about this. He was clear that DT40 is for the 996 and DI40 for the direct injection cars like my Macan Turbo.

Quotes source post: 20549151

i have spoken to Jake and Driven racing. They confirmed that the DT40 was developed for the M96 with high molybdenum content to help prevent bore score. Driven agreed that their web site is misleading as it stands but confirmed what Jake told me. For track applications I believe that the DI50 is also fine.

Everybody should do themselves a favor and watch this video. You Tube

Quotes source post: 20561888

So, are you saying additives are not all created equal. Can understand that... Please expand on that. I'm thinking something like,,, some oils use MoS_2 type moly instead of regular Mo..? Or do they go to an organic Mo...? Because if I remember my Chem classes Mo is Mo. Purity and concentrations are weeded out with the PPM tests we all see in spec sheets, aren't they..?

Quotes source post: 20562943

Yes, exactly. Additives are not all created equal, and this applies to friction modifiers like moly just as much as it applies to ZDDP, VI improvers, detergents, dispersants, corrosion inhibitors, and anti-foam agents. Moly is a perfect example. When you see molybdenum on a VOA or UOA, the lab is generally reporting elemental molybdenum ppm. That does not necessarily tell you what molybdenum chemistry was used. It could be an oil-soluble organomoly friction modifier such as MoDTC, MoDTP / MoDDP, a molybdenum amide, another proprietary organic molybdenum compound, or in some cases a suspended solid such as molybdenum disulfide, MoS₂. To the elemental analysis, those may all show up simply as �moly,� but they do not behave the same in the engine. That is the important distinction. �Mo is Mo� only at the elemental level. The chemistry carrying that molybdenum matters. Different moly compounds vary in solubility, activation temperature, friction-reduction behavior, oxidation stability, compatibility with other additives, and the type and durability of tribofilm they form on the surface. For example, MoDTC is widely used as an oil-soluble organomoly friction modifier. Under boundary-lubrication conditions, it can react at the contact surface and form low-friction molybdenum disulfide-type tribofilms. That is very different from simply dumping solid MoS₂ into an oil. Both involve molybdenum, and both may be associated with MoS₂-type surface chemistry, but the delivery mechanism, stability, filtration behavior, treat rate, and interaction with the rest of the oil formula are not the same. That is why two oils can both show, for example, 80�150 ppm moly and still behave differently in service. One oil may use a moly chemistry that activates quickly and works well with its ZDDP, detergent, dispersant, and antioxidant system. Another may use a different moly compound that is less effective in that particular engine environment, or that depends on a different supporting additive chemistry. A basic ppm test does not tell you that. It's a limitation of the testing methods available to us. ZDDP is another good example of why ppm does not tell the whole story. When a VOA or UOA shows zinc and phosphorus, it does not tell you which ZDDP chemistry was used. ZDDP is not one single additive. There are primary ZDDPs, secondary ZDDPs, mixed primary/secondary ZDDPs, different alkyl chain lengths, and neutral versus basic ZDDP forms. These differences affect reactivity, thermal stability, oxidation control, volatility, corrosion behavior, and how quickly and effectively the anti-wear tribofilm forms. More zinc is not automatically better; the right ZDDP chemistry in the right balance is what matters. VI improvers are another example. One oil may use a more shear-stable viscosity modifier, while another may use a polymer that provides a wide viscosity spread but shears down more quickly. Both oils may meet the same SAE grade when new, but they may not stay there in the same engine after heat, fuel dilution, and mechanical shear. Detergents and dispersants are not interchangeable either. Detergents help keep hot surfaces clean and neutralize acids, while dispersants keep soot, oxidation products, sludge precursors, and other insolubles suspended so they do not form deposits. Calcium, magnesium, sodium, boron, or nitrogen numbers may give clues, but they do not identify the exact detergent or dispersant chemistry, molecular structure, treat rate, or how it interacts with the anti-wear and friction-modifier system. Corrosion inhibitors and anti-foam agents are usually even harder to judge from a data sheet, yet both are important. Corrosion inhibitors protect ferrous and non-ferrous metals from acids, moisture, and other corrosive byproducts, especially in engines that sit, see short-trip operation, or experience fuel dilution. Anti-foam agents help prevent aeration, which can affect oil pressure stability, hydraulic lifters, bearing-film strength, and heat transfer. True race oils, like Driven XP oils, have better anti-foaming packages than the street oils- yet another reason to run a race oil on the track. This is why I do not judge an oil simply by base stock, zinc ppm, moly ppm, or a few data-sheet numbers. Those numbers are useful, but they are not the whole formula. Finished oil performance comes from the complete additive system, the quality of the components, the base oil blend, and how everything works together in the actual engine. I remember reading once in an SAE whitepaper the suggestion that the byproducts of the oil additives formed during engine operation (exposed to combustion byproducts, heat, friction, etc.) actually outperform the raw components. In the paper, it suggested that it could take up to 1000 miles for this to occur. I've also seen numerous tests carried out with used oil versus new oil. So again, numbers don't mean much here. The used oil analysis is what tells the true story. And while I'm critiquing the whole oil table, let's talk viscosity. A higher HTHS number is useful, but it does not tell you how the oil got there or how well it will retain that viscosity in service. Again, that's what the UOA is so important. As Lake Speed Jr. often points out, oil formulation is about balance. More of one additive is not automatically better, and adding something aftermarket can upset a finished formulation rather than improve it. A VOA tells you part of the recipe; a UOA, used in context, tells you more about how that recipe actually performed. Lastly, this isn't my first rodeo when it comes to testing oils. I've done the whole test every oil (and additive) to see what's in them. I spent tens of thousands of dollars doing oil testing back in the early 2000s. Both testing new and used oils along with weeks spent at Jake's on the dyno. That's how we caught the attention of Lake, back when Driven was still under Joe GIbbs Racing. That's how we ended up with DT40 and DT50. Data might be old (see my uploaded Excel file), but it does show that formulations have changed since the early 2000s, at least on an elemental level. I know I have all the dyno testing data somewhere along with the UOAs, but that was well over 20 years ago. Lucky I still have that old excel file.

What a treasure trove of oil information!!

Quotes source post: 20562908

Great video, thanks! @Charles Navarro why do you recommend DT40 and then say you personally run DI40 with Lake in the video above? No spears, just curious. I have been running DT40 and I�m due for an oil change, you guys make DI40 sound like the way to go in that video. Im a street only kind of guy but I do occasionally give it a good run.

Quotes source post: 20563378

Price. DI40 costs more than DT40. Simply that. There is no reason why you couldn't run DI40 though if you don't mind the added expense. The biggest jump in wear reduction comes from switching to DT40 from an A40 oil. You don't have to take my word for it - there are plenty of other threads with people who have shared their UOAs.

And while other's UOAs can be a helpful guideline, they won't accurately reflect your driving style and use case. If you want to objectively find the best oil for your situation, then you'll need to run some UOAs on your engine.

Quotes source post: 20563547

I have run two so far since I�ve owned the car. Once as soon as I got it and once at my first oil change. The first one I guestimated the mileage based on when the previous owners receipts. About to do a third but I�m not overly familiar with what I�m looking at on these.

Quotes source post: 20563248

Great post, thanks for explaining that...!!! What is your opinion of Cera-Tech MO additive...? In your testing has it shown if a 'good' effective type of MO is used in VR1 20-50 syn...? How about in M1 racing ? Motul 50, Liquid Moly 20-50, Redline, Amsoil Dominator ? Any spec sheets that you've accumulated over the years that could help show different oils hidden properties...? What is the correct amount of MO needed in a oil. Seems even Driven uses different concentrations, as in double the ppm in DT vs DI. What is the correct concentration for the 996 m96.?

Quotes source post: 20564389

I haven't tested anything in years. I haven't seen the need to. The UOAs for Driven still come in great. That's all I need to see. My opinion still stands on Ceratec. It does improve the performance of LM A40 oils, but it does drop the viscosity some. But I wouldn't use an additive unless I had no other choice.

I had a really interesting conversation with Driven. One thing I learned is that the DT oils have been updated to use the same VII and additive package brands as the DI oils, so they�re now very similar oils with the main difference being that the DT oils have a higher detergent level for more street-oriented use. The other interesting piece was their HP-X 10W-60, which is PAO-based, sounds like it could potentially be a really good fit for our engines.

mPAO inherently has very strong shear stability due to its stereochemistry and has a very high natural VI so a 5W-40 isn't going to need a lot of VII. Given that it is likely combined with ester and/or AN, it will need even less VII. It's going to be a lot more of a concern with a 50 grade and especially a 60 grade oil, especially when paired with lower winter ratings. The reason DI40 has lower Ca detergency compared to DT40 is to prevent LSPI particularly with turbocharged direct injected engines.

Quotes source post: 20570150

Thank you for that! That answers my original question and reason for the thread! Among the Driven oils, I think I would go with DT50 for my paritcular engine and types of driving. Amongst all the uncertainty, in the meantime I decided just to go with VR1 20w-50 Full synth. Im gonna run it for a couple thousand miles and send it off for testing. Ive sent of the Liqui Moly 5w-40 I ran for the last 2200 miles to Blackstone. I will see what everything says and then pick one and continue to test.

Quotes source post: 20570383

You made a good choice, VR1 is great oil, don't let the talk of the "quality of additives" lead you to believe VR1 has a low quality additive package, it does not. And even though I asked this particular question here on this forum, no one here has ever claimed that.... Valvoline VR1 Synthetic racing oil is considered to have a high-quality, robust additive package, particularly designed for high-performance, flat-tappet, and racing engines. From what Charles has said on this thread, MoDTC is a good organic moly additive. post #99 "Valvoline VR1 Synthetic 20W-50 racing oil uses premium Moly-based friction modifiers, often identified as Molybdenum Dithiocarbamate (MoDTC) or similar organic moly compounds" For our prone to oil pressure instability foamed aerated oil M96 engines, this is a nice feature in the VR1 additive package... "Anti-Foam Agents: The formula includes specialized anti-foam agents to ensure stable oil pressure under extreme stress and high RPM conditions"

SInce we're talking oils and such. This is the first run of Motul 300V 5W-50. Still running the oil given the numbers of the latest results. Will change before 10,000km cannot workout why fuel dilution started out poorly but has come back over time. Driving style hasn't changed. And virgin test I did

Nice, I like the fact that you have samples at 5000 and 7000 km. It looks like a great oil for your engine, and I look forward to the 10,000 km sample.

Quotes source post: 20563422

Received my order from you guys today, DT40 it is for my use. Money isn�t really a factor for me (not when it comes to oil changes) but I�m going to stick to DT40 until my use case changes or the UOA shows otherwise. Appreciate the input from everyone!

Here is the UOA on the Liqui Moly I just changed. I had added 1 bottle of Ceratec a few hundred miles before I changed the oil. I know, kind of a waste, but it was only half the recommended amount for that size oil capacity. The only figures that should affect on this analysis are Moly content though, I think.