I did an oil analysis on my 996 Turbo.

It came back with abnormal levels of fuel in the oil (8.8% where it probably should be close to zero).

It also had a viscosity in cSt at 100°C of 11.5 where Mobil's European Mobil One 0W-40 should be 13.4:

<a href="http://dallnd6.dal.mobil.com/Apps/DS/_39gj50ko_/MobilPDS.nsf/26b7c4b33367a4a086256665004e4266/48949cdadd4294fc852567f3006a781c?OpenDocument" target="_blank">http://dallnd6.dal.mobil.com/Apps/D S/_39gj50ko_/MobilPDS.nsf/26b7c4b33367a4a086256665004e4266/48949cdadd4294fc852567f3006a781c?OpenDocument</a>

Detailed results can be found here (ID# 2574):

<a href="http://members.rennlist.com/oil/" target="_blank">http://members.rennlist.com/oil/</a>

What's even more interesting is that the engine has been checked and no problem found.

So, has anyone else done an oil specrochemical analysis on a 996 Turbo or GT2? If so, what results did you get??

If you haven't, I highly recommend you do (and let me know the results!).

S.

 

[quote]Originally posted by cjv:
<strong>
I believe what you experienced is normal. My guess is you have been driving the car around town and not very hard for about fifty miles or so before you had the analysis. I believe if you ran it above 3000 rpm's for awhile there would not have been any fuel in the oil. Many people check their oil after light usage, drive it hard for a bit and discover the oil level low. That is because the fuel that was in the oil evaporates.
</strong><hr></blockquote>

Not at all CJ!!

My car is almost exclusively used for high-speed, long distance driving. It spends most of its time above 4500 to 5000 RPM. The car is never used for commuter type driving. Over the long hall, my average speed as measured by the computer is about 90 km/h which is well above what most people see.

Also, the oil is drained twice as often as normally recommended.

This is why I was so surprised at the results.

I actually think 9% would even by high for someone who did commute regularly in their car. I would expect even this worse case to be no more than 5%.

S.

 

In researching this, one of the things that I have discovered is that there is a variation in viscosity between the Mobil One 0W-40 sold in the USA and the Mobil One 0W-40 sold in Europe. They are both called 0W-40 but this is only possible because the SAE standards are so wide.

Specifically:

In the USA the viscosity in cSt is:

At 40°C: 80.3
At 100°C: 14.4

In Europe the viscosity in cSt is:

At 40°C: 71
At 100°C: 13.4

Both are different products with different viscosities but Mobil is able to call them the same thing because, for example, the SAE J300 viscosity specification for an SAE 40 engine oil is 12.5 - 16.3 cSt@100C. The standards are wide enough so that both products fit within it.

So what does this mean? Well it means that when you buy Mobil One in Europe you aren't necessarily getting the exact same product. Interestingly, Mobil's European 5W-40 is actually closer to their USA 0W-40 product than is their European 0W-40 (84, 14.3).

In my own case this is important because it is a factor in the test results I got.

S.

 

Nop. In fact I was very careful to drain the oil right after a long, hard drive for exactly the reasons you give (though I doubt even in that circumstance it would be above 5% and probably even less in our engines).

As I recall, I had just driven to Antwerp and was doing about 220 km/h.

The day prior I had been at Nürburgring so about 500-600 km including track time. The highway portion at least was at 230-260 km/h.

So I agree. A very strange set of circumstances.

Anyway, the car will go back to Weissach to be checked in January.

S.