I don't completely agree with MarcW ...

I have been using Mobil 1 since I took delivery of my '00 S (~3/00). I used the grades as recommended by the owner's manual. The car has always run good, so I never had a reason to try a different oil.

But after reading all the hype about the reduction in zinc additives in motor oils and their effect on flat tappet engines, I decided to try an oil that was recommended by many sources including LN Engineering.

I did an oil change in January and used SynTech 5/40. I have about 800 miles on the oil now. The engine seems to run a lot smoother. A bit more responsive under acceleration too. I have experienced this since the oil change.

It may be anecdotal, but it is definitely a noticeable improvement. It is typical that new oil gives an initial improvement, but never for this long after a change.

YMMV.

the ingredients of oil when one can find them are listed by percentage of weight. For instance, the ingredients in Castrol Syntec 5w-40 is synthetic base stock, proprietary performance additives.

Specifically, base oil, highly refined is listed as making up 90% to 95% of the oil. This info from Castrol MSDS data sheet.

This means 5% to 10% of the oil, by weight, consists of additives.

One way of looking at this is to weigh a container on a precision scale and zero the scale then pour in a quart of this oil. Then pour out oil until the scale reads 5% to 10% less than it did. What remains in the container represents how much *oil* the quart of oil contains.

It is the oil that provides the lubrication that keeps the engines parts from touching, helps conduct away heat from the hotter areas of the engine (the bearings.valve stems, and rings), and carries around whatever additives are in the oil to help with corrosion resistance, provide detergent action and so on.

BTW, ZDDP only comes into play if this oil breaks down and can't perform its job. One thing that suggests itself is that an oil that contains a large dose of ZDDP is a substandard oil which the presence of ZDDP is intended to address. Cheaper I guess to load an oil with ZDDP than it is to make the oil, well, better. This is not a slam against Castrol oil though since I believe the ZDDP level in Syntec oil is low.

Thus an oil that has a large (relatively) speaking dose of additives, is in some respects a lesser oil than one that has less additives.

The history of ZDDP is that it came about to help prevent wear of flat tappet engines. This was back in the change over from flat head engines to over head valves. This change led to higher output, higher rpms cause in most case overhead valve engines breathed better and could run at higher rpms. This higher output and higher operating rpms of course results in more heat and more demand upon the oil.

But as engine designers/makers and oil refiners learned how to properly deal with the differences between the older style engines and the newer ones, ZDDP and its like became less necessary. One reason is as I pointed out above the more there are of addtives, the less there is of oil.

Another benefit from ZDDP or other additives is they make the oil 'thicker' and this of course results in a quieter engine. Whether this means the engine is subject to less wear I can't say. I have observed with all the various oils I've run in my cars that an oil change quiets the engine some, mainly due to the old oil having been contaminated with water and unburned gas and thus becoming thinner over time. A new oil of course contains no water and unburned gas and is thicker, naturally, and thus the engine ought to be quieter.

Sort of related, but I'm having the Boxster's oil changed today and the dealer is using Mobil 1 0w-40. (I just had the Turbo's oil changed (car was in for a broken shifter and I picked up the Turbo just this AM) and I had the dealer use Mobil 1 5w-50 oil (which is also an approved oil). Anyhow, I'm curious as to how the Boxster's engine will sound with 0w-40 oil in it and with nearly 242K miles on the engine.

Sincerely,

MarcW.

Just got the Turbo back the other day with Mobil 1 5w-50 and the Boxster is getting (has gotten) Mobil 1 0w-40 oil. I didn't have enough Mobil 1 5w-50 on hand to use this in the Boxster and I tried to find some at a local car parts store and it doesn't carry it. The same name brand parts store carries it over here in Hayward and then there is a Mobil oil distributor just a few blocks away from my office. But I wanted the Boxster's oil changed and I didn't want to wait. Besides it will be interesting to hear how the engine sounds with all those miles with 0w-40 oil in the engine. If it sounds too bad I'll replace the 0w-40 with 5w-50 myself.

Sincerely,

MarcW.

... since I believe that including additives makes for a better (not lesser formulation).
If motor oil's only intent was to lubricate parts, then I agree, but motor oil serves many other functions as well:
• Cooling
• Protecting
• Cleaning
For these additional requirements is that pure oil needs to be fortified.
These additives help with heat transfer, anti-wear and internal cleaning, among others.
ZDDP, Zinc DialkylDithioPhosphate is probably the best anti-wear agent there is for oil, but it's regulated because of environmental issues.
In my point of view, for my car, the more the better.
I had used Mobil1 15W50 because it had the highest amount of ZDDP in the market (Phosphorus:1200 ppm, Zinc: 1300 ppm)
I now use Mobil1 0W50 Racing because it contains Phosphorus:1750 ppm, Zinc: 1850 ppm.

If you'd like to read more on oil, here's one of the Tech Articles I've written for a couple of dozen PCA Regions:
[www.pedrosgarage.com]

Happy Boxstering,
Pedro

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




Edited 1 time(s). Last edit at 04/23/2011 07:20PM by Pedro (Weston, FL). (view changes)

I did not know you switched oil again Pedro.
You use to state in your warm climate that you used a 10 or 15 something 40 or 50.
Is 0W/50W also suitable for street cars?
Seems like you are going for the highest phosphorous/zinc content.

i agree with Pedro. ZDDP is being reduced for one reason: Catalytic Converter life.

This is a good thing, on the surface. But if you dont burn oil, there is no way for the ZDDP to get to your cat a foul it. So, if you burn appreciable oil, avoid oil with hgih levels of ZDDP. If, like me, you appear to burn zero oil, WTFC?

On a more general level, additives are the most costly component of oil, liter for liter. So additives are used sparingly in some cases, when more would in fact bee good. In other cases there is a right amount and more is not better - e.g.: some detergents, and anti-foam agents that have other side effects.

I honestly think that changed reasonably, all the above will provide good service. And off track, none of this [probabl] matters.

Grant

willing to sacrifice a $12K (or more) engine for the sake of extending the life of $2K converters?

I agree somewhat with Pedro's point that additives are to help fortify the oil but a good oil should need little in the way of fortification. A few percent of additive can't help much in heat transfer, there's just not enough of it to make any difference.

Mostly there is ZDDP and detergents. A big does of detergents is overkill for high quality sythetic oils at least Porsche gasoline engines. AFAIK, none of the approved oils have high levels of detergents.

A heavy load of additives can make the oil run hotter because these additives make the oil thicker and thus the oil generates more heat from fluid friction.

Mainly what I think Porsche is after is approving a good oil, one that relies upon the quality of it base stock(s) and a sensible amount of additives. An oil loaded with additives is not a good oil for these engines.

Sincerely,

MarcW.

And Porsche really has to go along with them.

Add that to the fact that 99.x% of its customer base does not drive hard, and therefore does not need it, and voila.

Yes, i'm somewhat cynical. But i've spent a lot of time on industry technical standards, and it ain't pretty.

Ditto thin oil recommendations (5w20; 0w-anything, ...) - that's for CAFE.

Grant

based on SAE viscosity and the API and ACEA specs are the 'same' as the approved oils these oil are not approved, are not on the approved list.

I believe Porsche uses something besides/beyond just these various auto/oil/government clasification/grading standards to construct its list of approved oils. And I think it is as you hint at: These standards have been so compromised that they have become nearly useless as the sole basis for judging the suitability of an oil for a given application.

Sincerely,

MarW.

And they all require lower zink, etc.

I'll go one better based on non-exhaustive observation. The porsche spec is simple:

ACEA A3/B4. Plus some minor addition. A3/B4 means HTHS >= 3.5+ (which is marginal)

Grant



Edited 1 time(s). Last edit at 04/24/2011 08:04PM by grant. (view changes)

ironically enough this issue is addressed in this months Excellence Tech Forum and they recommend oils with a high level of ZDDP and SAP to reduce wear on the valve train, but what does Tony Callas know? He doesn't even participate on a car board.

Motul which is ester based and low on ZDDP. Motul is on the approved oil's list.

Tony Callas -- I vaguely recall coming across the name -- doesn't/can't speak for Porsche regarding oils unless he's willing to stand behind what he recommends if for instance someone comes in and says I followed your oil advice and the engine is sick and I want it fixed.

Also, even the Porsche engine builders can't agree. I have a co-worker running a breathed on 993 3.6l engine in his 914 and the engine builder (Jerry Woods IIRC) recommended he run Mobil 1 0w-40.

Sincerely,

MarcW.

Several grades of Motul have very high ZDDP and that is why it was recommended it is also one of the Oils Callas recommends to get high levels of ZDDP.

Motul 5w-40 8100 x-clean and 8100 x-max. Even the Motul 15w-50 6100 Synergie oil lists no ZDDP in its ingredients.

The 1st two oils have a bit (between 1 and 2.5 percent) (by weight) of a long chain alkyl calcium salicylate. This is a detergent and dispersent and provides for alkalinity reserve (corrosion resistance?).

The 6100 oil has less than 3 % of two calcium compounds: calcium alkaryl sulfonate and calcium alkuyl phenate.

Sincerely,

MarcW.

just what do you think Zinc alkyldithiophosphate is?

[grandprixregion.com]

[www.callasrennsport.com]

aside from being the real name for ZDDP.

Note there are other additives that can perform the same function - many being soft metals.

The issue is that under high pressure and wiping actions ( think: cams) you can go from Hydrodynamic lubrication ( all this stuff about weights and film strength out the window) to boundary lubrication - meaning the two parts just collided and are about to grind against each other. Then you want a sacrificial soft solid to keep them somewhat apart.

ZDDP. Moly. Heck, microscopic brass!

Just keep it off your cat

Grant

Quote
old timer
just what do you think Zinc alkyldithiophosphate is?

[grandprixregion.com]

[www.callasrennsport.com]

material safety data sheets (MSDS) for the oils I named for ingredients and no ZDDP or anything like it was listed as an ingredient.

Other oil makers list ZDDP as an ingredient worthy of well listing, even Mobil 1 with its Turbo Diesel Truck oil which has 8 ingredients listed and all 8 are listed at 'Trade Secret 01' through 'Trade Secret 08' yet still under the section Composition/Information On Ingredients, besides

1-DECENE, TETRAMER AND TRIMER HYDROGENATED (20 to 30%)

which I think is PAO, also listed is

ZINC DITHIOPHOSPHATE (< 2.5%).

Anyhow, for the two Motul 5w-40 oils I mentioned in my earlier post I found just the polymer LONG CHAIN ALKYL CALCIUM SALICYLATE stuff I mentioned listed along with

DISTILLATES (PETROLEUM), HYDROTREATED HEAVY PARAFFINIC (50 <= x% <= 100)

and

DISTILLATES (PETROLEUM), SOLVENT-DEWAXED HEAVY PARAFFINIC (0 <- x% < 1).

So I would have to say based on the info I have on Motul oil, at least the 2 5w-40 8100 series oils that are Porsche approved oils, ZDDP is not in the list of ingreidients.

Sincerely,

MarcW.

The whole point of this discussion is that political pressure in the form of regulations and monetary penalties has caused automakers to alter their recommendations so they have. Oil company's have also altered their formulas. That's not to say the new oil is not good it's just not the best. You are sacrificing the parts when contact occurs to save your planet. Now it is very unlikely that any of the wear cause by the lessor oils will cause a problem while the car is under warranty so a valve train problem will belong to the cars owner not Porsche.

The brands recommended by the writers at Excellence are recommended because they are in the owners best interest not the planets.

Quote
old timer
The whole point of this discussion is that political pressure in the form of regulations and monetary penalties has caused automakers to alter their recommendations so they have. Oil company's have also altered their formulas. That's not to say the new oil is not good it's just not the best. You are sacrificing the parts when contact occurs to save your planet. Now it is very unlikely that any of the wear cause by the lessor oils will cause a problem while the car is under warranty so a valve train problem will belong to the cars owner not Porsche.

The brands recommended by the writers at Excellence are recommended because they are in the owners best interest not the planets.

ZDDP and other similar additives provides no real benefit. If it did, if it was truely needed and given the number of vehicles that are not using oils with these higher levels of ZDDP et al, we would I think see worn out engines, flat lobed cams, worn faces of lifters, etc. right and left.

We have not seen this.

Also, if these additives are not benefical, if the oils containing these higher levels of addtives are not the best, or are even harmful in some ways, we'll not see the effects of this for some time.

So right now all is rosy and everyone's going out and seeking out the oil with the most ZDDP and detergents and what have you believing that represents the best oil.

When the people making the claims that oils with high levels of ZDDP and recommending these oils be used instead of an approved oil, when these people actually stand behind their recommendation that will be something.

Right now, if one has a new car and something goes wrong due to the wrong choice of oil, the factory eats it. That is unless the factory has an oil analysis done and finds the oil is not a recommended oil due to the oil's wrong signature.

In some cases Porsche techs are under Porsche/PCNA orders to take an oil sample from the engine and send it to a lab in the USA Porsche has contracted with for just this purpose. So Porsche is at some level analyzing oils in the engines that come in that are sick or have a possible oiling related problem.

But when someone says use a high ZDDP oil and if something happens that is oil related and the factory declines to cover the problem because a non-approved oil was use we'll cover it, well, that would be when I would start to possibly believe all the wonderous benefits of ZDDP et al that these people state may be true.

Sincerely,

MarcW.

... vs boundary lubrication. I suggest people go and read what i wrote under "unpronounceable" but any soft metal or similar additive is a last resort under high pressure, sliding conditions when hydrodynamic lubrication fails. At this point all the talk of flow, viscosity, etc is moot.

When does this occur? Under pretty extreme conditions. In fact, most of thsi talk matters not under say to day conditions. For normal use its more important to have low levels of moisture and additives, ability to fight sludge, etc.

But if you are racing, or running very hot ( various conditions, towing comes to mind) etc - this stuff matters.

Discussing lubrication at the margin, and then saying that "most" data points don't support it, is nonsensical. Of course they don't - they are not at the margin.

There is no technical debate over whether ZDDP, molybdenum disulfide, or similar additives decrease wear in boundary lubrication situations were the only alternative is metal to metal abrasion.

Grant

conditions, IOWs using an oil that can provide proper lubrication that never sees this boundary conditon happen.

I think running oils loaded with ZDDP et al is just false security. People are fooling themselves or being fooled into thinking 250 to 1000ppm ZDDP, moly, etc. is going to make any difference when the oil breaks down to the point metal to metal contact takes place.

And if ZDDP is so good for an oil additive at between say 250 to 1000pmm, why not 2000ppm, or 5000ppm? What is so magical about the current levels? How much testing have these oil companies done with Porsche engines to know that Porsche engines have the same ZDDP needs as every other engine? That many are recommending oils with high levels of ZDDP for Porsche engines suggests they believe the ZDDP requirements for Porsche engines are high. One hopes then the off the shelf oils have ZDDP levels sufficient for Porsche engine requirements, yet this suggests they are too high for other engines and owners of those cars are overpaying for these Porsche high levels of ZDDP.

Furthermore, if this breakdown is happening it is happening under considerable load, heat and high rpms conditons and while this metal to metal contact is prevented (one hopes) by the presence of these additives there is the heat load that results from this boundary condition protection and this can work to compromise further the metal to metal interfaces that these additives seek to protect. It is the oil flowing through/between the bearing surfaces that remove the heat.

Then there is the question as to how much of this additive is consumed or itself broken down in doing its job in protecting the engine from all these boundary condition events, so the next time it is needed there is less of it or what remains offers less protection?

This suggests early oil changes of oils with higher levels of ZDDP are advised, because well, if one is running these oils the assumption is metal to metal contact is being dealt with often. Additive depletion becomes a concern. and well, and more frequent oil changes certainly need to be considered to ensure this oil has a sufficient additive package to ensure adequate protection.

Anyhow, it is your car, so use oils with high levels of ZDDP if you want which I guess means if you believe the people advising you do this know more about the car and its engine and its oiling/lubrication requirements than the people who designed, built, and warranty the car you bought. I think this use oils loaded with ZDDP advice is ridiculous (and if anyone with a car under warranty that follows it risks voiding the warranty and then the advice could be considered harmful) but I'm apparently in the minority.

Sincerely,

MarcW.

Quote
MarcW
which I guess means if you believe the people advising you do this know more about the car and its engine and its oiling/lubrication requirements than the people who designed, built, and warranty the car you bought.

Sincerely,

MarcW.

no need to believe that. I *know* from both friends who work in the auto industry, and fiends who formulate motor oil , that both are under significant pressure to promote thinner oils (fuel economy); long drain intervals (reduce toxic waste) and reduce additives that damage emissions (cats). It is a fact.

So there is no need for a 3rd party, selling a product promoted for "after warranty use in high mileage vehicles" to know more. They merely need to be honest, and feel less pressure re: mainstream oil policies.

For obvious reasons, no more details will be forthcoming.

As to the issues of how much ZDDP. I have no idea how much testing they did. More than me, and likely more than you. I also know that whatever their testing and calculations, they have been reducing levels consistently, while under gummit pressure. I conclude that it is likely the earlier levels were preferable purely from a protection standpoint. I also acknowledge that on balance, for the general public, the damage to cats may well outweigh the small benefit in terms of last ditch boundary protection.

But i don't pretend it doesn't exist!

Note: - in many ways i agree with you. i don't scour the world looking for high zinc oil either. for 99.?% of us it makes no difference. I also agree that i'd rather have an oil that defers the need for boundary lubrication. but i need not choose - i can have both if i want. M1 15w50 comes to mind. Note that 5w50 is not as thick, despite the apparent claim that it is. It depends on VIIs. yes, it does. As dos 0W40. But i also realize that under extreme conditions, zinc is a benefit. and that if one's car does not consume oil ,there is no mechanism for it to reach the cat. Therefore the benefit/cost ratio is high ( the denominator is for all practical purposes, close to zero)

Grant

... I think I'll stick with my choice of M1 15W50 or 0W50 Racing.
To me, the more ZDDP, the better!
Happy Boxstering,
Pedro

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

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

So, what you're sayin', if I understand, is that I should stop draining my dirtbikes and puring the used oil in my P-car?

I had 0W40 M1 in my 986. Was about to do a series of DEs for the hot summer. Decided to drain out 5 qts and put in 15w50 (so i now had a mix that was roughly 7.5W 45, yes, it really works that way..). Since it had < 1500 miles on it, i captured it in a clean container, and put it in my old Audi 2.8 v6. better than the 10w30 dino stuff it has survived on all these 15 years.

Bear in mind that old oil - even lightly used old oil, is full of contaminants - moisture, acids, mainly.

Grant

I had, or found a similar experience with our families cars. I've used Castrol Syntec(10w-40, ACEA performance rated) for a few years now with great results. I was having too much rough running, coking issues, and oil consumption with the M1. It was also getting hard to find the ACEA performance rated M1. Whereas, the Castrol Syntec is easy to find around us and costs less.
regards

I just jumped in with you with yesterday's oil change, so we'll see how it goes (formerly M1 0W40). I was wanting to bump up a little bit on the viscosity as I just passed 90,000 miles plus it doesn't get that far below zero in the winter here.

Also in the back of my head, 30 years ago I had a shiny new RX-7 that burned oil of every kind I put in until I tried Castrol - and then the oil consumption of that Wankel engine just stopped. So I have a soft spot for Castrol for reasons that have nothing to do with conditions thirty years later.

/side note: I traded off that RX-7 for a brand new 924 Turbo in 1983.



Edited 2 time(s). Last edit at 05/01/2011 06:54PM by Tom (Powell, OH). (view changes)

is purposely designed to consume oil, the oil being fed to the engine to help lube the rotor seals/wipers.

Sincerely,

MarcW.