bernocco930S

WOW, that is a LOT of reading. ..... let's see..... where is my owners manual? It's time for an oil change. If I go to a heavier oil does that change the torque spec on my drain plug?????

Blackness

Just as a side note, I found it interesting that at Sebring last weekend, the RS Spyders were running Mobil 1 0W40. Hmmm...a 480bhp @ 10300 rpm engine running 10/10's for 12 hours straight with a 40 weight oil (in Florida).

Ray S

Blasphemy!!! It's obviously the reason they lost!! If they had used a thicker brew they would not have had so many mechanical problems.

How dare you side with Porsche engineers!!

BruceP

Don't make me get all Oliver Stone on your ***. It's as plain as day that the whole thing is a conspiracy. Make people use bad oil, then their cars will break. If a lot of cars break, people won't like Porsches. If they don't like Porsches, they won't buy them, and if that happens the company will go broke. And who benefits from that? Well, you didn't hear it from me, but a friend of a friend told me that Dick Cheney went short on Porsche stock...

I'm just sayin', is all .

Blackness

Hehe...I was wondering if I should have brought that up considering they lost to the friggin' Acura's. (On the Acura's first time out, no less.)

If I knew that the Evil Emperor owned a share of Porsche stock, I would strongly consider selling my 911. Certainly more so than the Spyder's losing to the Acura's.

Doug Hillary

Hi,
without wishing to debate more erroneous "facts" proffered by 1999Porsche911, the following information may help readers understand the relative viscosities of two Approved and one Non-Approved (15w-50EP) Mobil 1 lubricants - at the oil temperatures most relevant to our engines;
The M1 5w-50 formulation is the Canadian and not the Euro version

All viscosity figures are in cSt - the higher the number the more viscous the lubricant is!

At (20f) -7C (A random cold start temperature)
0w-40 = 530
5w-50 = 761
15w-50 = 1292

At (180f) 83C (A normal coolant thermostat "crack" point)
0w-40 = 22
5w-50 = 27
15w-50 = 30

At (190f) 87C (A typical oil cooler thermostat "crack" point)
0w-40 = 20
5w-50 = 24
15w-50 = 26

At (200f) 93C (A normal oil operating temperature)
0w-40 = 17
5w-50 = 21
15w-50 = 22

At (230f) 110C (An "elevated" but normal oil operating temperature)
0w-40 = 11.3
5w-50 = 13.5
15w-50 = 13.6

At (20f) -7C, the difference in viscosity is very significant. The real meaning of the 0w, 5w, and 15w low temperature ratings can clearly be seen

At oil temperatures rise progressively up to (180f) 83C, the SAE40 oil is much less viscous. This ensures rapid circulation and a minimum time spent in lubrication system by-pass and in filtration differential by-pass. Getting the oil's temp to equilibrium with the coolant's temp is a real task as the oil trails behind by up to around 20C for many minutes

Modern anti wear (AW) additives begin to become progressively effective above around (130f) 55C. Modern synthetic lubricants function best in a (195-230f) 90-110C range

The viscosity band at (210f) 100C for SAE40 oil is 12.5 to 16.3
The viscosity band at (210f) 100C for SAE50 oil is 16.3 to 21.9

From the above you can see that a both M1 SAE50 oils are already in the SAE50 band at (200f) 93C and that the SAE40 oil is also operating in the SAE50 band too!

This is one reason why the SAE40 oil (M1 0w-40) is very well received by Manufacturers and a factory fill with such as Porsche, MB, AMG and etc. It has a successful record in tracked engines and is well endorsed by Factory Technicians. It is a very robust oil indeed

I have no connection at all with any Oil Company

Regards

Ray S

Doug,

Thank you for your analysis. It's very interesting!!

bernocco930S

2004 996 C4S @ 65,000 miles. So here is the bottom line question for me. XXW50 is out of the question BUT is there a no-brainer answer to the question of 0W40 VS 5W40 FOR MY APPLICATION??
Thanks in advance I will listen....... eric

Doug Hillary

Hi,
bernocco930S - yes it is all really very simple, follow the latest Porsche TSB, there are about 100 Approved oils Listed there

M1 0w-40 is suitable for ALL normal operating conditions and remains one of the best engine lubricants ever made - regardless of price!!

A 5w-40 viscosity lubricant is suitable if your ambient is generally above -12f (-25C)

Only use Approved and Listed lubricants and don't add any chemical supplements regardless of what you read!

Regards

bernocco930S

Thank you Mr. Hillary. I forgot to mention that I am in Southern California so I think I read you load and clear. Cheers, eric

bernocco930S

BTW Mr. Hillary. Do you know anyone down under that might be in the market for a 1989 930S factory car, one of only 28 coupes made that year? Thanks in advance, eric

Doug Hillary

Hi,
Eric - please send a private message with all details of the car

I know Southern (& Northern) California quite well having driven from North to South and lots and lots in between. Your climate is like parts of OZ. I live in the Tropics on the edge of The Great Barrier Reef about 1100kms north of Brisbane

Regards
Doug

Thanks

1999Porsche911

I guess for those of you without an oil pump. the Kinematic Viscosity is really important? Kinematic viscosity, (CST) measures the viscosity of oil as it flows under the force of gravity and NOT pressure and this measurement does not transfer equally to the flow of the same oil while under pressure. Many of us with an oil pump prefer to look at other important oil ratings.

However, the CST DOES play a role in how fast the oil will fall from the lubricated parts (like valves and bearings) when the engine is shut down, allowing you to enjoy those nice engine startup noises. The lower the cst, the faster the oil drains away.

It is amazing how the many years of marketing efforts have saturated the minds of so many, but even more amazing is the number of people who simply accept hype as fact and that, some how, lab results transfer to the real world.

We all know the claim that startup produces the most wear on an engine, which, of course, is true. What many do not know, is that, as I stated above, at moderate temperatures a 0W40 and a 15W50 will flow under pressure the same volume of oil in the same amount of time. Is oil pressure higher? Yes it is, but flow is virtually equal. Does the 15W50 bypass the filter or other parts of the engine as some here claim? Not at all. Therefore, in this example, wear caused by a difference in oil flow does NOT exist. The difference that does exist is the lack of oil that has remained on the lubricated parts BEFORE any fresh oil gets to it. As stated above, the 0W40 oil will leave less oil on parts after engine shut down than will 15W50 oil.

Like that low, low oil pressure at idle? Sure wouldn’t want a hiccup in the engine when the bearings and crank aren’t under proper pressure. Pressure is an important factor in keeping your parts from hitting each other. I wonder how many of these blown engines are due to low oil pressure and how many of these engines that burn oil were damaged because of low oil pressure and no shear protection?

I sure hope that those of you who plan on keeping your engine for a long time, do a little research on your own and make an intelligent decision and not just follow the conscientious. Remember, the conscientious proved that the world was flat….didn’t it?


The choice of oil is a compromise. I am not going to rehash all that has been said, but some things are worth repeating. Burning oil is NEVER a result of something good happening in the engine. It is never normal for any engine to burn oil, regardless of how many of you may be experiencing it. Burning of oil ALWAYS results in a reduction of engine performance in late model cars. If you are having piston slap at startup, valve noise, leaking or burning of oil, erratic surging when cam timing changes, rough idle after everything else has been corrected and are running 0W40, why would you not try changing to a better oil and run it for a few thousand miles?

There are many on this forum besides me who have done so and stated that they have seen an improvement AND their engines didn’t blow up!!!!

If you don’t want to use 5W50 or 15W50, at least get rid of the 0W40 and more to a 5W40 or higher.

CosmosC4S

1999Porsche911...I don't care what others say about you,
I believe you know quite a lot about Pcars,
You often give good advice to help others,
and you know what you are talking about.
That is all.

Doug Hillary

Hello,
1999Porsche911 - as I said earlier I will not be drawn into a debate over the erroneous "facts" that you promote! Your Post number 73 above is just simply full of misinformation and whats more in the last sentence you say this;

"If you don’t want to use 5W50 or 15W50, at least get rid of the 0W40 and more to a 5W40 or higher"

1999Porsche911 - Both the 0w-40 and 5w-40 engine lubricants are SAE40 Oils !!!!!!!!

I strongly advise anybody reading Post 73 to submit it to a Professional Lubricants Engineer (not a Salesperson) or a Lubricant (Oil Company) Chemist or Professional Blender to ascertain the true level of misinformation it contains!

I will not debate this issue with 1999Porsche911 further as after some months and in various Forums on here he has simply spread very little meaningful information but a large amount of harmful misinformation. I won't waste further time or effort!!

Regards
Doug Hillary