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YOUR RESEARCHWhat do you use for engine oil?
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Replace back; i've been
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No other factors changed back; I've been using an LN spin-on adapter and the same Napa filter all this time.
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Suggestion
As long as you have good, clean oil that's well made - and I believe there are way too many out there that fit the bill - you will be fine for general street use.
Leading evidence: 'Replace back; i've been' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Clean oil' (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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Last week I changed my oil and used Liqui Moly 5-40w because of a write up in PCA's website claiming up to 20 more HP by using Liqui Moly and their additives.
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It ran 5 solid minutes with no cooling before it failed.
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I'm running Castrol Syntec 5w40 and will probably stick with it
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I have run DT40 0w40 every since having IMS replaced in my 2002 C2 at 96,000 miles, but recently, when temperatures hit 122 F in Palm Springs, my oil pressure seriously drops at idle because (I assume) the oil is too hot and too thin.
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Clean oil
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Suggestion
As long as you have good, clean oil that's well made - and I believe there are way too many out there that fit the bill - you will be fine for general street use.
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Suggestion
No unexpected coolant level changes; no smoking issues, AOS tests good with my digital manometer, no visible difference in output from one bank than the other as far as tailpipe deposits, visible condensation @ cold start.
Replace intervals and overheating, etc., cause engine failure issues
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Suggestion
I know that extended change intervals and overheating, etc., cause engine failure issues but irrespective of that, will DT40 in a stock engine really reduce the failure risk?
Last week I changed my oil and used Liqui Moly 5-40w because of a write up in PCA's website claiming up to 20 more HP by using Liqui Moly and their additives.
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I purchased the flush, oil saver and Cera Tec along with the type of oil and have noticed no difference from my regular Mobil 1.
What are folks using for engine oil? I will soon need to change the oil on my '99 C2. For my earlier 911's I use Mobil 1 0W-40. Is that a good choice for the 3.4?
Thanks!
I'm an idiot
wrong tread
@James - You'll get a lot of flak for asking this given how many threads already cover the topic. Spend 30 minutes reading a few threads & you'll get a good feel for what oil meets your intended use.
My car came with fresh 0-40 Mobil 1. I left it there and swapped it for 5-50 for summer/track use only. You can keep using 0-40 unless you are really hot climates.
Hey, I did a search and nothing much came up on the 996 forum. Go to the 993 forum if you love popcorn.
PS-Tony, my Fister D mufflers should ship next week. I got the ceramic coating.
s
Nice work, I'm excited to be done with exhaust mods
.
I use DT40 and have used Mobil 1 0w40 before learning about the engine's propensity to devour oil that doesn't have good resistance to sustained, elevated temps. Switching to Motul 8100 Excess reduced oil consumption for me and now on DT40 I barely went through a quart in the last 3,000 miles. So I'm staying on DT40. Other guys run Motul with success & others have 100+ k miles on Mobil 1. Royal Purple is another one some guys use.
The wet sump system in the m96 isn't the best for high-performance driving, particularly on the track. So 996s are more susceptible to loss of viscosity from running at high temps.
A good DIY you could do is figure out what temps your car runs at (oil & coolant) with your normal use. Then select an oil that works well at that temp + a dozen or two degrees for margin of safety. The inadequacies of the m96 wet sump manifest in localized hot zones, particularly in bank 2 (pax side). So there's a long list of failed m96 engines thanks to bank 2 weaknesses.
Mk1s your main risk is cracked heads, whereas mk2s are more susceptible to cylinders being compromised. From my perspective, a 10-20k+ engine is worth $100 oil. And I drive my car a lot, with 2-4 oil changes per year so far.
Keep on combing through the old threads & you'll find more information to incorporate into your decision making. There's a good Blackstone oil analysis thread that you can participate in to understand what level of metals are running through your engine. If you're running clean oil I think you're in good shape (assuming you don't decide to run the 996 in an endurance race at a track).
Started running DT40 almost 20,000 miles ago, and now at 166,000 my mild oil consumption (about a quart every 3,000 miles or so) has actually decreased. Oil analysis reports look good, and car runs great.
(You're getting off easy here! When I saw the thread title I thought you would get way more abuse! I've had trouble searching for things in old threads, but oil "discussions" shouldn't be too hard to find.)
Walmart now sells Pennzoil Platinum Euro 0w40 for $25 for 5 quart bottle. It is Porsche approved and only $2 more per 5 quarts than the mobil 1 0w40 for those of you with mobil 1 derangement syndrome and want a reasonably priced alternative
I would never use Pennzoil, or Royal Purple, since I've had my 996 (5 months ), I've used mobil 1 0w40, but might switch to Amsoil 5w40 next change. Amsoil is the only oil i used in my previous car , a track prepped Sti.
Just finished a shorter interval with Castrol 0W40, currently have Pennzoil 0W40 in the sump. Previous owner ran M1 0W40.
If I ever do a track day, I'll probably look at FSI's recommendations, otherwise I'll stick with a brand name xW40, a 5K interval, and not sweat it too much.
And, FWIW, Motul 8100 5w40, Wix 51042 filters on a LN spin-on filter adapter. 5 liter jugs of Motul usually run about $35 shipped through Amazon Prime, a little less if you catch a sale elsewhere.
I like to wait outside my local autozone with empty milk jugs and buy oil from people bringing it in to recycle..... J/K. Oil preference is almost as daunting as the age old: blonde, brunette or redhead question.
James, I am new here and found many things don't come up when I do a search on the forum. However, if you do it a google search it will sometimes bring up two or more threads on the subject.
BTW: I am in Houston and run Mobil 1 5/40 FWIW.
Not only is google a better search engine for rennlist, it also includes Renntech, Planet9 & others that have great content scattered amidst the chatter.
We have the DT40 in a nice kit including filter and magnetic drain plug, use coupon code RENNLIST for 5% off.
Kit for 996:
https://rennpart.com/product/oil-change-kit-complete/
Individual bottles:
https://rennpart.com/product/driven-...synthetic-oil/
Last week I changed my oil and used Liqui Moly 5-40w because of a write up in PCA's website claiming up to 20 more HP by using Liqui Moly and their additives.
https://www.pca.org/would-you-give-c...ore-horsepower
I purchased the flush, oil saver and Cera Tec along with the type of oil and have noticed no difference from my regular Mobil 1. Maybe the benefits, if any, have yet to come. It's only been about 100 miles so far.
that 20hp is probably only realized on an 800 hp engine with sludged oil in the crankcase. Mobil1 is low enough friction, there is no way changing to a different oil will net you a 20hp gain. As a long time car guy, I seriously despise the aftermarket and their often ludicrous power gain claims. 20 hp is about 0.2 seconds faster in the 1/4 mile. That's nearing something one can notice using a butt dyno. 20hp is a huge gain.
Come on man...the PCA article was sponsored by LiquMoly and the results provided weren't even for a 911. No way you're going to get that type of HP increase from an oil change.
If you truly want to go down the motor oil rabbit hole, here are a couple of sites to really get you started:
https://540ratblog.wordpress.com/201...-test-ranking/
https://bobistheoilguy.com
Oh, man ... the FSI competitors are ramping up their press releases as we speak: "Raby says M96 owners should switch to canola oil, DT40 prevents beneficial engine wear."
Just kidding, Jake ... I've got Motul 8100 in the sump, but I'm still saving up for a 3.6 FSI rebuild.
I used this in my 996, it is heavy duty and comes in 2 gallon jug. No issues in AZ heat.
https://www.walmart.com/ip/Super-Tec...r-Oil/16213443
For trans and brake fluid I used this one. Does fine job and gear engagement got much smoother after the flush. Put it in the braking system too, never had a problem.
https://www.walmart.com/ip/Super-Tec...mrI#about-item
Use a 0w40 or 5w50 engine oil. Porsche approves Mobile 1 in both grades. In theory the 0w40 offers more protection in cold climates due to the 0w viscosity being able to lubricate in sub freezing temperatures.,and the 5w50 offers more protection in warm climates with better viscosity at higher temps.
In the Netherlands you should fine with the 0w40. As long as you change your engine oil every year or 5000 miles you'll be fine. Note that Mobile indicates a longer change interval.
As for DT40 not being available, that is irrevelant. There are plenty of excellent lubricants available.
I'm sure that I'll get slammed for this response but I stand by it.
Why bother slamming you?.......it will just get deleted. Do have some nekid pics of the mods for them to delete posts to an...........wait for it.................OIL THREAD?
Hurry up, for your own benefit.
I've ran an engine at wide open throttle in front of 500 people until it failed... Ran on a mixture of Panama Jack and Hawaiian Tropic suntan oil. It ran 5 solid minutes with no cooling before it failed.
Upon teardown the oil was clear, and didn't even smell burned. That was back in 2002.
No "oil rabbit hole" here. Porsche did their research and decided Mobil 1 0-40 or 0-50 was what they wanted me to run in their engine design. Even printed it right there in the owner's manual, rendering any rennlist oil thread utterly useless.
Theres no way that could have been monetarily or politically influenced... No way. Right?
Remember, those same people also brought us 29 modes of M96 engine failure. I couldn't thank them enough. Love those guys.
I love 'em too. Every Porsche (and any other..) I've owned has had some degree of misstep in design or execution of some major part of the machine. And yet, here we are- driving, repairing and loving them still.
Yes, and the car might be 95% perfect, but as we discover flaws, we can just live with them or find ways to remiediate or improve them. That's where all these aftermarket solutions come from. If there wasn't a better way, some of these aftermarket solutions would not work and never sell and there would not be any reason for these companies to be in business. Granted, there's a lot of crap out there, but less crap out there for Porsches.
Oil happens to be a choice a manufacturer has to make based on a myriad of factors, and concessions and compromises have to be made. One the one hand, all top class 5 oils are probably "good enough," but since a Porsche engine is so damn pricey, good enough turns into a risk worth exploring.
I run Mobil 1, but I don't think it's the best oil for these cars in specific situations, such as a track day.
I still have 3 drums of slightly used DT40, so I haven't _bought_ oil in a while. Thanks, KK!
Seriously, though: I use DT40 because the kool-aid tastes great. Prior to that, I was using Total Quartz 9000 Energy per my indie's recommendation, but he's not as convincing with the sugary instant drinks as others...
^^ lol
My indy drinks Motul 8100 xcess. He let me taste it, it was mildly sweet with a reasonable monetary bite. I'll be getting the really sweet stuff for my next track day.. 300V
If this was true, there wouldn't need to be an approved oil list. Since Porsche lists a number of oils at more than one viscosity, "useless" might be a bit extreme. How about "99.99999% useless?"
Hah!
I'm genuinely interested and I'd think we all are! I know that extended change intervals and overheating, etc., cause engine failure issues but irrespective of that, will DT40 in a stock engine really reduce the failure risk?
Someone more intelligent than I am can explain how the additive loads can reduce wear and perform other seemingly magical feats. The various additives do some amazing sh*t.
https://en.wikipedia.org/wiki/Oil_additive
There is one passage in that Wikipedia article I found especially enlightening (assuming it's true and not hyperbole):
"Nearly all commercial motor oils contain additives, whether the oils are synthetic or petroleum based. Essentially, only the American Petroleum Institute (API) Service SA motor oils have no additives, and they are therefore incapable of protecting modern engines."
If we accept the concept that a modern engine's life can be drastically shortened if the oil does not have the correct additives as truth, it seems a logical extension that an additive package could be developed to help ameliorate known issues with a specific engine.
Oil, is better than no oil. We can all agree with this much.
Now, not that the courts get it right 100% of the time, there are many documented cases of additive claims not being proven. Slick 50, STP etc...
Please put oil in your 996. Motor oil is better than cooking oil. Although I have read that Copper Tone can produce an extra 30HP for a very short period of time in a 996TT.
[Image-only post; no author-written text. Original image references:]
https://cimg3.ibsrv.net/gimg/rennlist.com-vbulletin/285x213/package_d5b667e5446b245038104e5e013427f4a5aa3cf8.jpg
Blackstone Labs attempts to answer this very question using their data. The results? It pretty much doesn't matter which oil you use...
https://gallery.mailchimp.com/f64139...Aug_17_ENG.pdf
Not too surprised, but one thing i don't understand is why a longer oil change interval would result in lower iron found in the oil. They should have accounted for this in the beginning.
The true mindf*ck of this whole discussion is that Blackstone's conclusion can be perfectly valid for the engines they monitored and completely invalid for engines they didn't review. You'd need some metadata and a good sample size to draw any serious conclusions about the m96.
It's easy to assume things that aren't appropriate if you don't put a fence around what you truly know. If the guys that live & breathe m96s and m96 racing say something, it'll take a lot of data for me to go against their word.
Yeah, but "their word" is purely anecdotal. None have been running race cars with multiple oil types, then logging wear and failure rates. Raby, if anyone, prolly has the only empirical data.
I asked Blackstone if they would either a) run this same analysis on M96 motors or b) send me the data and I'll do it. I'm guessing the answer to both will be "no," but it's worth a shot...
I see no reason why a company that specializes in testing oil - and presumably has thousands of data point - would not be one of the best sources of data anywhere. Thier data actually correlates to bobistheoilguy.com and other oil manufacturer sites that describe test among different oil with a conclusion that the idea that "all class 5 top oils" will work pretty much equally well.
The other comment I have is with regard to 0-40 Mobil 1. Didn't Porsche list that oil for the 996 from day 1? If yes, hasn't it been 18 years with no change? I'm not saying it's a perfect oil - far from it. But with tens of thousands of 996s running it, and no correlation to IMSB failure or any other engine failures, I cannot see how this oil wouldn't be anything other than "perfectly fine" for most everyone in their 996s.
Of course, many folks don't trust that, and have switched to something else, and yet, we don't see problems with those oils either. Strange? Not if a top oil is a top oil.
How many of us have threads that go into deep detailed comparisons on other Porsche fluids? Most recommend Porsche fluids for Coolant, gearbox/diff, power steering. Yet motor oil has to be so different because we believe it's the lifeblood. As long as you have good, clean oil that's well made - and I believe there are way too many out there that fit the bill - you will be fine for general street use.
I have this little sticker on my engine lid. It came from the Porsche factory that way. Since mine was manufactured 7/98 (sold as a 99), it is close to 20 years old. I have 140K miles and daily drive. I run Mobil 1 0-40 with an LN oil filter adapter and magnetic plug. I also use a Mobil 1 oil filter. I change the oil/filter about every 3,000 miles and consume none in between. Guess I'm doing something right.
2013 Porsche Super Cup Car (notice what it says on the front fender)
I have very little inclination, nor desire, to try and outsmart a bunch of Porsche engineers, Porsche testing, or my own experience. Especially at my age. Everybody is free to do what they want and run what they want. Just sharing.....not trying to be definitive.
and some of that sponsorship money?
I know two pro teams that are sponsored by Mobil but do not run that oil in their engines. I'm sure there's more than that .
same goes for Mutul,and I've even taken the oil to that particular shop and witnessed it poured into an engine.
never believe a sticker on a race car. Never
I gave up on trying to convince people what to do. I realized that the best thing for my business is for them to follow their inclinations, and factory directives. Why tell them any different? No reason.
It was at that time when I became selfish and only made directives for the owners of my engines. That's when I realized that those people are the only ones that rate my recommendations. Send me an oil question and it'll get deleted, not replied to.
So yes, today I love some Mobil 1!
B3 Freak, that's not a machine gun. It's a drum fed Saiga-12 shotgun. I have several legally registered class 3 weapons, but that one isn't NFA regulated.
Crazy to think the Mobil sponsored car doesnt run Mobil oil. Sad, but could be true in today's corrupt corporate culture.
But, my guess is that its top secrete and only a few people on the race team know the truth. Midnight, before race day they do a quickie lube oil change and put in Copper Tone super lube.
Full dry sump vs. a strained & out of place wet sump system is a big delta to cross with assumptions. Pros in any discipline will migrate towards what works best, or at least what gets the job done. 2 of the 2 LN certified techs I've worked with have been clear about their preferences, so I use what the most knowledgeable people I know use. To each their own, drive what you want & be happy.
So there is this report from Blackstone. I expect there will be much wailing and gnashing of teeth.
https://www.blackstone-labs.com/News...uly-1-2017.php
I'm gonna weigh in here and suggest that whatever money/ royalties, sponsorships or anything else suggested here paid by Mobil 1 (or anyone else) is not going to be enough money to sway Porsche into risking powertrain warranties, short or long term reliability, or 60+ years of general brand reputation on that kind of business decision. I mean, seriously?...
I should've known that because last time I posted that picture, Kalash pointed out it was a Saiga-12. Then, I just happened to look it up in Wikipedia and look in the main paragraph. Talk about coincidence.
my 106k mile 996 survived a day of hpde running motul xcess 5w40 although it was rainy and not particularly hot.
I prefer the vepr to the saiga, personally. Get em while you can.
I have run DT40 0w40 every since having IMS replaced in my 2002 C2 at 96,000 miles, but recently, when temperatures hit 122 F in Palm Springs, my oil pressure seriously drops at idle because (I assume) the oil is too hot and too thin. Still going to use DT40 but heavier weight. Change oil every 3000 plus and have no loss.
With apologies for perpetuating yet another oil thread ...
My Touareg also requires copious quantities of 5W40 - I put in 8+ quarts last time. The 996 gets DT40 but if y'all want to save some $$$, RockAuto have Pentosin 5W40 for $30.79. "Designed for German automobiles" apparently - YMMV if you want to put it in your beloved 911, obviously.
They wouldn't take risks on cheating emissions systems to lose billions either, would they?
Its all about the bottom line. Anything that helps that bottom line is the goal.
With the info available it would be hard to argue that DT40 is impressive, but have any of the tests had some sort of control sample to compare to? For example, a boxster with mobil1 0w-40 driven along with the boxster with DT40 on its Parade road trip, and then the wear and failure rates compared between the two?
I have this. Its not shared as it is proprietary to my engine program, as all evaluations were down with my Street Performer, and Track Performer engines. This started in 2007, and continues today.
Engines were assembled for this specific purpose based on the standard menu for each aforementioned base engine. They were then used, and abused, and in one instance drive 8,800 miles in a 10 day period, then disassembled and re- measured.
Trying to share stuff like this is a waste of time. That sticker they placed in the back of the car was really effective. I finally gave up and realized that people's bull- headedness, and attitude about this was the best thing for my business for the long haul.
It was at that time that I only gave a damn about what was built here, and thats because people pushed me to do that.
The future is really bright....
The world needs DT40 stickers that are just big enough to cover the Mobil1 decal on the engine lid. My m96 doesn't need to be constantly reminded about a past, abusive partner. It's just not nice.
Amsoil Dominator 15/50 here.
Just spent 3 days at BIR in 85 degree heat.
Hitting 150 or so on every lap in every session. Full throttle pulls down the mile long straight.
6 turns in 3rd gear around 6k. 4 turns down shifting from 5th to 3rd.
1 large smile from ear to ear.
That ole Jake magic at work all day every day.
And they say it can't be done. They don't know Jake.
I'm likely not the only one here that uses Shell Rotella T6 year round. Multiple oil/filter changes throughout the year.
Bought in bulk, I change the oil and filter between nearly every track event for around 8-10x total changes per year under $50 per with filter.
Overkill in a lot of respects but it works for me. Oil analysis coming soon.
With an LN single row pro upgrade IMS, They and my indy suggest Motul 5/40
Purring like a kitten with it and no oil use and clean reports from Blackstone.
Napa Gold filter to add to madness.
Rather than start my own oil thread (I'm not THAT stupid), I thought I'd post this question here (because I am still
fairly
stupid):
When I first got my 996, I changed it to TOTAL Quartz Energy 9000 5W40 and ran it that way for the first year or so. I switched to (popular oil here on RL), which is also a 5w40-weight oil, and ran THAT oil for two years.
During the time I ran oil B, I burned about 1/4 quart of oil per 1K miles. My car had never burned oil before, so I was a little concerned. No oil in coolant; no coolant in oil. No unexpected coolant level changes; no smoking issues, AOS tests good with my digital manometer, no visible difference in output from one bank than the other as far as tailpipe deposits, visible condensation @ cold start. Intake was free of accumulated oil; nothing leaking onto the garage floor.
As SOON as I switched back to oil A, my car stopped consuming oil. Like, nary a drop. Still no change in coolant level, and no coolant in my oil. No other factors changed back; I've been using an LN spin-on adapter and the same Napa filter all this time.
1) Is there any way this is actually a legitimate observation, or is there some obvious cause I'm overlooking? No significant changes in where the car lives, where I've driven it, the fuel I buy, or anything else I've identified.
2) If you think it's possible: WTF? Learn me good.
Have you checked oil viscosity differences between the two oils at 90 or 100C yet? It could be that both oils are not the same viscosities. Besides that, there are many differences between two seemingly similar oils that can cause what you experienced.
This is a source reference. Confirm exact model applicability in the original material.
