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Topic Re: Yea, i keep bringing it up because... |
Oil talk Jim in Iowa - Sunday, 6 October, 2013, at 4:22:58 pm |
Terrific writeup Laz - Sunday, 6 October, 2013, at 5:37:53 pm |
Re: Terrific writeup +1 Guenter in Ontario - Sunday, 6 October, 2013, at 7:07:32 pm |
High levels of ZDDP can actually cause wear. The ZDDP under heat/pressure reacts... MarcW - Sunday, 6 October, 2013, at 8:59:40 pm |
Another reason to change the oil, or at least the filter Roger987 - Sunday, 6 October, 2013, at 9:21:56 pm |
Have you ever seen evidence of spalling from ZDDP in the real-world? First hand? Papers? grant - Monday, 7 October, 2013, at 2:34:42 pm |
GM supposedly is the company that looked into this. Here's a link... MarcW - Monday, 7 October, 2013, at 4:35:12 pm |
I'll follow that link, thanks. Still sounds like noise in the system at first glance. *NM* grant - Tuesday, 8 October, 2013, at 7:29:09 pm |
Eeek! MArc, you didn't mention that they were talking about over 0.2% - that's like 10-20x grant - Tuesday, 8 October, 2013, at 7:34:54 pm |
Non gas oil additives are listed by weight. For instance the amount of ZDDP in 15w-50... MarcW - Wednesday, 9 October, 2013, at 10:04:48 am |
Thanks for posting Roger987 - Sunday, 6 October, 2013, at 9:08:01 pm |
Re: Thanks for posting Ed B - Monday, 7 October, 2013, at 9:27:14 am |
Re: Oil talk gedwin - Monday, 7 October, 2013, at 9:43:45 am |
It is not how far you drive per day but how hot the engine gets during that drive... MarcW - Monday, 7 October, 2013, at 10:07:38 am |
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gedwin
"I then asked about interval changes. He said that during warranty, it's important to always follow the manufacturer's guidance. He added that 95% of the oil samples that they receive *didn't *need to have their oil changed. The oil was not worn out, nor was there too many wear particles in it. So much for the 3,000 mile oil change myth vs. data."
This is interesting. I still wish I could get a better answer regarding whether I am wasting my time changing my strictly street driven 981's oil at 5K when the interval calls for 10K. I drive far enough every day to burn off condensation, and don't mind changing more often if the engine needs it. I just don't like wasting time, money, and oil if it is not needed.
The quote above tells us to follow the manufacturers guidance, but that is a minimum, and we know that. It states that 95% of samples didn't need changing, but we don't anything about those samples (miles, usage, etc.).
Re: It is not how far you drive per day but how hot the engine gets during that drive... gedwin - Monday, 7 October, 2013, at 1:55:27 pm |
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MarcW
I used to put cardboard on my radiator in the winter. After reading that, i may again! *NM* grant - Thursday, 10 October, 2013, at 8:18:39 pm |
Yea, its that "area under the curve" bit - it comes down to grant - Monday, 7 October, 2013, at 2:31:48 pm |
Why is my used oil black? Bruce In Philly (2000 S Boxster, now '09 C2S) - Monday, 7 October, 2013, at 2:12:26 pm |
those are detergents doing their job.... grant - Monday, 7 October, 2013, at 2:27:46 pm |
Hoo boy - lots of good advice here - but also lots of "except that..." grant - Monday, 7 October, 2013, at 2:25:34 pm |
Can you tell us if Mobil 1 0-40 Euro (factory fill) had a hard time? *NM* Laz - Monday, 7 October, 2013, at 4:31:24 pm |
It would not be appropriate to say that, either way, no, but i can say that grant - Monday, 7 October, 2013, at 9:29:48 pm |
Based on what oils Porsche approves all of its approved oils have an upper limjit of viscosity... MarcW - Monday, 7 October, 2013, at 4:44:45 pm |
Yea, i keep bringing it up because... grant - Tuesday, 8 October, 2013, at 8:19:34 am |
Re: Yea, i keep bringing it up because... Guenter in Ontario - Tuesday, 8 October, 2013, at 8:41:07 am |
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grant
For the rest of the world, i'm sure that relatively fresh 5w30 is fine. Just don't expect it to protect at 100+ deg C and hgih rpms. Which, on my morning commute occurs roughly, well, never.
Grant
That's pretty hot. I dont have a oil temp guage in my boxster, but grant - Tuesday, 8 October, 2013, at 11:08:35 am |
Re: That's pretty hot. I dont have a oil temp guage in my boxster, but Guenter in Ontario - Tuesday, 8 October, 2013, at 2:33:32 pm |
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grant
In my Audi i typically run about 170-190 degF; on the track i have hit 230-240F. That was a hot day, running dfoot to floor pretty much all the time (pocono).
100 degC is simply the typical temp for hot viscosity measurements. Note there is no magic number; there's a fairly smoo9th viscosity curve vs temperature.
Grant
Re: Yea, i keep bringing it up because... MikenOH - Tuesday, 8 October, 2013, at 5:25:38 pm |
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Guenter in Ontario
Quote
grant
For the rest of the world, i'm sure that relatively fresh 5w30 is fine. Just don't expect it to protect at 100+ deg C and hgih rpms. Which, on my morning commute occurs roughly, well, never.
Grant
From a cold start, it takes a LOT longer for the oil to reach operating temperature than it takes the coolant. I think it's part of the 981 thermal management. Coolant will be near operating temperature (90 C on Canadian cars) before the oil temperature begins to rise much above ambient temperature. At around 20 C (68 F) it can take anywhere from 10 - 15 minutes for the engine to reach operating temperature. For me, I consider that to be 90 C for coolant and oil temperature. I always avoid hard acceleration and high RPM's before the engine is fully warmed up.
And its not like we need to drive weasy until its 95 dec C - opil is flowing incrementally grant - Tuesday, 8 October, 2013, at 7:21:15 pm |
Well, I'm no oil expert but my recollection is the concerns about VIIs... MarcW - Tuesday, 8 October, 2013, at 10:24:44 am |
VIIs adn better vs different grant - Tuesday, 8 October, 2013, at 11:23:06 am |
I've regularly seen oil over 200 F, but the motor's never been run at nearly continuous high rpms. Laz - Tuesday, 8 October, 2013, at 10:45:49 am |
A3/B4 and HTHS - doesn;t matter? grant - Tuesday, 8 October, 2013, at 11:29:46 am |
OK, now i'll take 10 minutes grant - Tuesday, 8 October, 2013, at 11:52:04 am |
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Jim in Iowa
others call it (or Mobil, in particular) a marketing scheme.
--> its both. But anyone in the busines knows these are paid for endorsements.
The PCA's tech editor Alan Caldwell (a retired Boeing engineer) did an extensive look at oils, and concluded that so long as the oil is Porsche-approved, and the second number in the formulation is 40 or higher, change at factory intervals, and you are good to go.
--> the problem is that car's duty cycles are different. If you drive the car regularly, adn get the oil hot, and burn the moisture offr, and dont add too many acids, then yes. If all those if's dont occur, then no. And there are wide differences in the Totoal Base Number for A40 oils, so they simply can;t be identical in terms of counter-acting acid.
Excellence magazine's tech staff recommends using Motul, often with much more frequent than the factory recommended change intervals. You'll see a bunch of other places recommend changing oil every 3K miles.
--> in general i think that buying by brand is misleading. Buy by numbers. Changing frequently is also good, btu one has to know why, adn beyond x its just wasteful. Interestingly, when i do UOAs my track cars have vastly lower dilution - THEY GET HOT
One really interesting question I saw posed at the 2009 Mobil 1 Parade tech session, during the 9x7 generation of cars, Porsche shortened the drain interval. I forget the exact number, but maybe it went from 15K down to 12K, something like that. Someone in the audience asked was that interval change due to the high frequency of ethanol in most U.S. gasoline, and as the alcohol is a solvent, does it strip the lubrication from the cylinder walls faster and break the oil down more quickly? Nobody answered that question, unfortunately.
1. Theyhave done thsi several times
2. moisture and acid are typically the enemy
Then of course there is the lowering of the ZDDP levels in oil in the last few years, a source of great consternation.
--> one reason, and its no secret - to protect catalytic converters. But i pose this: if your car burns no oil, how does the Zddp get to the cat?
To paraphrase Mobil's position, they told us that there are only two mass producers of the synthetic oil base stock in the world, Exxon-Mobil was one, and I forget the other, it might have been Royal Dutch Shell. So all of the various boutique oils are using one of the major's base stock, and putting in their own additive package.
--> not true. Maybe they make 85% or something, but there are small makers. Heck, look at the BP-EM lawsuit.
As to the ZDDP drop, Mobil says that's due to the EPA getting after the SAE (Society of Automotive Engineers), who do the oil certification. The EPA wants more life out of catalytic converters, I want to say a certain amount of effectiveness at 10 years instead of 8. The zinc and phosphorus metals build-up inside the cat, reducing its effectiveness over time.
--> absolutely correct, btu look above. Only if your car burns substantial oil.
Mobil says that ZDDP is a very cost-effective anti-wear additive, hence its widespread use. It's a relatively old additive, dating back to the late 1940s. They note that it's not the *only* anti-wear additive in the oil formulation array, nor is it magic, there are others, but they are generally newer and more expensive. ZDDP was popular because it works, and is low oost.
--> its about protection when you switch from hydrdynamic lubrication ( e.g.: oil film) to barrier lubrication (e.g.: oops, my oil failed at hgih temps and rpms)
The engines reportedly most prone to wear issues are those with "flat tappet' engines, such as the original Beetle. Mobil said that no Porsche motor from the 911 (1964) onward has that flat tappet condition (not sure on 356s).
--> yep, for us it only matetrs when the ehem, hits the fan
Some users have become fixated on reduced levels of ZDDP as being the potiential cause for many ills. Hemming's, the classic car car magazine, even markets a self-branded oil with high levels of ZDDP, "to protect your engine."
--> they are in the old car game. We are not.
Mobil, being aware of this stumbling block, has their "Racing" line of Mobil 1, so anyone insistent upon high ZDDP levels can get it. The EPA generally won't concern themselves with a "racing' labeled product, as they assume that's for off-road use, or small potatoes on road.
--> IMNSHO you are better off racing with oil that wont fail hydrdynamic lubrication. e.g.: hgih viscosity; low vis range; astronomical HTHS number. Oddly, this may be a hgih wear oil. But wear does nto mean "total film failure"
So that brings me to the lab again. When I asked what levels of increased wear were they seeing with these newer low ZDDP oils, the answer is "None." They base their judgment of how an oil is doing upon the wear metals coming out of the engine, and the measured characteristics of the oil. So it's interesting to see that wear metals are no different with lower ZDDP.
--> bingo per my above. If the film does nto fail, and the acid is neutralized, and the water boils off, under normal lubruication, wear is a non-issue. Problem is, many circumstances cause those failures. I would go out on a limb and say IMS's succumb to acid and water; track cars to oil film failure (or starvation of coruse, another topic)
Moreover, the flat tappet engines that have people so worried about wear, they're not showing up with any elevation in wear metals, either. When I asked for possible reasons why, he said they were using other anti-wear agents to replace the ZDDP, most often molybendum.
My next question was how do the various Porsche-approved synthetic oils do in their wear metals profile? Is Motul or Shell Helix, for example, better than Mobil 1? He said their lab hasn't seen any significant differences, they all do a fairly equal, excellent job. It's also interesting to note that the unit location averages in your oil report are for your type of engine, not all engines. So if you've got a 3.2L M96, they'll show you averages for other 3.2L M96s. I asked how big the population was for that group, and he said around 200 motors.
--> as i said
I then asked about interval changes. He said that during warranty, it's important to always follow the manufacturer's guidance. He added that 95% of the oil samples that they receive *didn't *need to have their oil changed. The oil was not worn out, nor was there too many wear particles in it. So much for the 3,000 mile oil change myth vs. data.
--> i agree about 3k for modern oils being short. But 1) it depends on your use 2) there is a giant self-selection bias in those who submit to UOA - they CARE. A 3k mile oil in a 1500 mile per year garage queen will be 30% oil 30% acid and 30% water,a dn 10% low. I'm exagerating, of course.
I asked what about time? Should engines always have their oil changed in selected time? That's usually once a year for Porsche. He said in warranty, always follow the rules. Out of warranty, mileage is more important. For automotive engines, they're so "tight' when it comes to environmental exposure (per the EPA), you don't have to worry about time so much. Now for piston-driven aviation engines, time is far more important because they're not as tightly sealed.
-->>no, no, no. That's literally true, but practically unlikel;y. Think about the characteristics by whcih a car gets to long time intervals but low miles. Sits. Accumulates water. Not too much use. Maybe rarely gets the oil hot for 30 minutes. In when it does, how hot? There will always be exceptions, but i would guess that garage queens have some of the worse dilution issues going. The best way to fix those is change the oil. Heck, use $8/jug dino. Its ph neutral at least!
I said hypothetically speaking, if you bought a new Porsche, would you change the oil early, or wait for the full year or 12K miles? He said he'd be tempted to change maybe before a winter storage to get the wear metals out, but you probably don't need to do it. He said most German engines these days don't throw off much in the way of wear metals, anyway.
--> again, its nto about wear metals. Its about shear (if you are a track rat), water and acid.
So it sounds as though Alan Caldwell's advice really is a safe way to go without overthinking it.
__> I prefer Einstein: things should be made as simple as possible, btu no simpler. we may have achieved "simpler than possible"
Thought you'd all be interested.