When hydrodynamic lubrication fails, you want something like ZDDP (or boron or titanium or....)

Not wanting to start a new oil thread just for the fun of it, but I’m hoping someone can make me feel better about which oil to go with on this next change.

I've taken responsibility to do the next oil change on Chuck's 03 S. I’m being indecisive on oils, which is primarily due to the overwhelming number of posts/opinions on which oil to go with -lots of opinions on changes in formulations over the years of different brands (Mobile 1 being a good example) and what that means for our engines. Of course, they’re all done with statistically meaningful sample sizes running validated test protocols.

Seems like the consensus here is that there are many good synthetic oils out there and that replacing it regularly is the most important and not to sweat it. However, I don’t want to be the guy who did the last oil change before the car had an IMS issue. Yes, as far as I’ve read, there isn’t a clear correlation between IMS failure and oil used, but I want to keep my conscience as clear as possible by sticking with those on the Porsche approved list. So while I see recommendations about 10w40 or even 15w50, if they’re not on the list they aren’t in the running. With that said, I tend to agree that a higher weight oil is probably a bit better, so I’ll go with an approved 5w40. Understood the A40 designation on the product designates it’s Porsche approved as well. The only ones on the list I’ve been able to locate (along with their part numbers) are:

Kendall GT-1 (1060743-AC)
Motul X-cess (102784-A012 or 007250)
Motul X-clean (102051-A017 or 102786-A016)
Pennzoil Ultra Euro (550022576)
Pennzoil Platinum (550016718)
Total Quartz 9000 Energy (185703)
Valvoline SynPower MST 5w40 (VV966)

Notice there aren’t any Mobil 1 variants -I don’t think there are any 5w40s on the list that are available in the US. Also notice that I didn’t include any Castrol ones? Marketing seems to have played around with the names (“SPT”, “Titanium”, “edge with Syntec technology”) so I’m not confident which ones are approved. Likely Castrol Edge SPT (06249) is, but can’t seem to find a part number matched with a datasheet showing A40 approval, and the [url= [url]http://pedrosgarage.com/Site_3/Porsche-Approved_Oils.html[/url]]Porsche approved oils list[/url] doesn’t go into these other naming conventions (and also says “Edge” is WW except for America), so I’m steering clear of Castrol for now.

I was previously leaning toward the Valvoline, but I may try the Motul X-cess instead.

Sorry for the wall of text, but does anyone have any input to make this decision more clear?

with low ambient temperatures a 0w-40 is probably best, but in areas where the ambient temperature is not real chilly 5w-40 is ok.

However, if you live where it gets quite hot consider using the 5w-50 oil (not a typo for 15w-50!). I think the next oil change for either car I'm going to switch to Mobil 1 5w-50. Both techs suggested it as it gets hot here in the summer. Have to point out though I've been running Mobil 1 0w-40 for years in all kinds of weather, including for prolonged times at up to 118F ambient temperature with no problems whatsoever. (I went through this switching from 0w-40 in the winter (what passes for winter here where I live) to 5w-50 in the summer (where it can get quite hot and did get up to 111F one late June day during a heat wave) but got tired of having to keep both oils on hand and then the oil distributor moved and I could no longer swing by the distributor and pick up 5w-50 on my lunch break, I just switched back to 0w-40 -- which comes out of the service bay oil gun -- and didn't think any more about it.)

Anyhow, it comes down to which of the approved oils is most available and then I guess at what price.

... Mobil1 10W40 High Mileage regardless of the mileage on their vehicles.
This blend has the highest amount of ZDDP of all of their street blends.
ZDDP is probably the best additive to extend an engine's life but the quantity (ppm) is regulated because of environmental regs.
Mobil1 was able to find a loophole in marketing it to high mileage vehicles which are grandfathered in, so-to-speak.
Happy Boxstering,
Pedro

PS: I'm not one to blindly and exclusively use products that are Porsche approved. Tires and oil, for instance.

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

---

Racecar spelled backwards is Racecar

"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

"If you wait, all that happens is that you get older"... Mario Andretti

"Being second is to be the first of the ones who lose" ... Ayrton Senna

Interesting. I've read up a bit on the ZDDP additive -seems like that might be the stuff to get. Of course, an alternative would be to get a bottle of the ZDDP and add it myself.

Of course, that still puts me in the position of using a non-Porsche approved oil.

Maybe ok in a Diesel engine but not in a high revving Porsche gasoline engine.

But again, for most drivers this is mostly irrelevant. Use a good 0w40 --> 10w40, adjust for how used and ambient temp, pick a hgiher TBN if oyu can, and insist on ACEA A3/B4 (which you will find correlates very well to A40).

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

else in the oil is going to keep metal to metal contact from taking place? For one thing a break down in the oil film means there is no oil to carry any of this magic additive to the bearing interface. There is also no oil to carry away the heat. The crank journal and bearing material are going to friction weld to each other in no time. And on top of that there is just not much of anything else in the oil. Mobil 1 0w-40 has IIRC 1100 PPM of zinc in it. This might prevent some scuffing at a cold start after the engine has sat over the season unused but at 6K+ RPMs on the track if the oil breaks down? No way.

It is the oil that protects the engine. Anything else is just marketing.

No time to go into all the details, but films break due to shear strength limitations - a stringer film will not break and there will be hydrodynamic lubrication - its lubrication 101. That's much of what HTHS tests for by the way.

As to barrier lubrication, yes, that is also proven via testing.

So, "yes and yes" but what i believe is not important - its what *is* that matters.

Why do you think A40 specifies a A3/B4 rating?

Why do you think for all time manufacturers spec thicker oil for warm environments?

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

.. all-questioning approach you bring to nearly any argument. There are lots of sacred cows that need to become acquainted with McDonald's.

But the failure mechanism associaetd with high-rpms and high heat and pressure is well documented, and fully endoprsed by Porsche in A40.

As to additives, again, its a very poor 2nd, btu if its a) dry bearing vs. b) dry bearing with soft metal or similar sacrificial material, i'll always take b)

while they correlate, HTHS viscosity, and hot viscosity are NOT the same. This strongly suggests that a bearing may be dry due to film failure specifically. While i have nto run the tests, my contacts confiirm this. note it only appleis to extreme situations of high (temp,. rpm, pressure) - not just one.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

This is a point always overlooked by who tout non approved oils.

While all A40 oils have the A3/B4 classification not all A3/B4 classified oils are A40. To me this strongly suggests that the A3/B4 classification is so loose, so open, so easy to receive, that all oils so classified are not in fact close the same and therefore one can't just rely upon that classification when selecting an oil.

This classification is quite loose enough that oils that clearly do not comply with in this case Porsche's requirements for a suitable oil (viscosity and make up) still have this A3/B4 classification and are advertised as suitable for use in not only diesel engines but gasoline engines too, including, if one goes by the oil maker says (at least on the surface) suitable for use in Porsche engines as well. But then everyone choses to ignore the fine print, which says in so many words that in selecting an oil to follow the automaker's guidelines. This in effect then says use our oil until the automaker says to not to. And in this case Porsche says to not use the oil, select an oil to use from this list of oils.

But of course some owners believe they know more about what's a suitable oil than Porsche.

You make (in error) the assumption I worry about A40. I do not. Just the opposite in fact. A40 gives me peace of mind because when I see an oil is A40 I trust it to be a suitable oil for my Porsche. As I have covered before and which is always conveniently ignored by those oil experts online is Porsche has the most to lose by specifying a subpar oil, any lubricant, or vital fluid for its fleet of vehicles.

I would worry if I decided to ignore the A40 approved oils for then I would have to either rely upon my ability to select a suitable oil or upon someone else's ability. I do not trust my ability to select an oil and I certainly would not trust anyone else's ability to select an oil for me. I mean everyone who elects to not use an A40 oil has their own selection criteria that is often at odds with the selection criteria of others who believe they know which oil is best. If one wanted to he could collect oil recommendations that would have the entire universe of oils "approved" for use in his Porsche, which I would then interpret that none of these oils selected by individuals are any good unless they just happened to snag an oil (probably by accident) that just happened to be an A40 oil. But for the online oil experts just the presence of A40 is reason enough to exclude the oil.

I went ansd dug out my report, made a JPEG, loaded it to tinypic, and linked it here. All because you wont trust me to have the facts, even if i dont reveal everything.

Here are the requirements for A40:

A40 reauirements

Point by point:

A40 doesn't specify any rating...

--> yes it does, see above

While all A40 oils have the A3/B4 classification not all A3/B4 classified oils are A40.

--> No shit sherlock, they need to meet the other requirements and Pay Porsche.

To me this strongly suggests that the A3/B4 classification is so loose, so open, so easy to receive, that all oils so classified are not in fact close the same and therefore one can't just rely upon that classification when selecting an oil.

--> What it suggests to you is irrelevant. on HTHS/ it is by no means loose. It means > 3.6 The absolute worst performing A3/B4 oil ont he market w/r/t HTHS is the one they recommend with a sticker, for which they are paid. in oil.

But of course some owners believe they know more about what's a suitable oil than Porsche.

--> i certainly dont say that. But i do say i know more about my environment, how my car is used, and i have less pressure to comply with CAFE.

You make (in error) the assumption I worry about A40.

--> I did not. I said Porsche knows what the cars need and specifies high HTHS
Porsche has the most to lose by specifying a subpar oil, any lubricant, or vital fluid for its fleet of vehicles.

-->No, it simply cannot blow up within 50k miles or 4 years, quite a low bar. The IMS fiasco shows that they dont pay too much attention to the reputation from technical folks

I would worry if I decided to ignore the A40 approved oils for then I would have to either rely upon my ability to select a suitable oil

--> yes, that is true. I don't mean to put capabilities in your brain, but you have more facts than Porsche has, if you begin with their own facts.

But for the online oil experts just the presence of A40 is reason enough to exclude the oil.

--> ok, now i get the sarcasm. But we should take any type approval for what it is. Since i was once in that game, i know quite well. its not bad, you just need to understand the motivations.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com



Edited 1 time(s). Last edit at 05/07/2014 07:06PM by grant. (view changes)

M1 0w40 is available everywhere and is on the list.

As is edge 5w40 SPT (that's the old syntec formulation)

I am often the one advising some people to run thicker oils, but please focus on the trade-off. For most daily drivers, thinner may well be better - it will flow better. For track use however, thicker oils may be necessary to retain a film strength at 6000 rpm, sustained WOT for 20-40 minutes at a 50% duty cycle or so. Temps get high, as do mechanical pressures.

You can worry or not about A40. I read the specs and work from there. in warm climates for hard-driven cars 10w40 is probably a very good choice.

The key is ACEA A3/B4. High TBN is also good.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Quote
grant
M1 0w40 is available everywhere and is on the list.

As is edge 5w40 SPT (that's the old syntec formulation)

I am often the one advising some people to run thicker oils, but please focus on the trade-off. For most daily drivers, thinner may well be better - it will flow better. For track use however, thicker oils may be necessary to retain a film strength at 6000 rpm, sustained WOT for 20-40 minutes at a 50% duty cycle or so. Temps get high, as do mechanical pressures.

You can worry or not about A40. I read the specs and work from there. in warm climates for hard-driven cars 10w40 is probably a very good choice.

The key is ACEA A3/B4. High TBN is also good.

Grant

I've looked for years to find independent evaluations of the types of motor oils I use and have found very little.
Do you know of any available tests that compare--head to head--similar oil weights from brands like Castrol, Mobil or the like?

1. done internally by blenders
2. done by labs for ACEA and API certs
3. done by manufacturers for their certs, such as A40, VW505 etc.

people in the labs dont obsess over brands nearly as much as we do.

I'm more and more convinced that we need 1) undiluted, 2) PH balanced and 3) proper weight for the use and environment (not "thicker is better nor the reverse).

For our cars we really do need ACE A3/B4, unless you putt-putt, at whcih point you dont

Grant

Grant

gee-lenahan-at-gee-mail-dot-com