Mobil 1 FS 5W50 4.5k mi; 2017 Porsche 911 3.0L Twin Turbo 6 cyl 27k mi

[Tier1Terrier]

Curious as to your thoughts on this Blackstone used oil analysis report. The report indicates a sudden & unexplained jump in fuel % from <.5% (where it consistently held for about 4 years) to 1.8%. The reporter comments that it's not considered an issue until it passes 2%. Any thoughts?

 

[6.7 CTD]

I’m no expert, but knowing that blackstone doesn’t use GC to measure fuel dilution and given the flashpoint of this sample; I suspect your fuel dilution may be worse than their reported percentage. I would try sending a sample to a lab that uses gas chromatography for more accurate fuel dilution results.

 

[himemsys]

First off, Blackstone's method is not consistent, and not accurate. Their 1.8% is actually probably 4-6% if measured directly via gas chromatography. Second, lots of possible reasons for the lower flashpoint. Did you idle a lot? More short trips than usual? Mostly cold weather driven in? These are all factors that could lower the flashpoint.

The fact that the wear metals look good and viscosity is not too low are a good sign. Maybe you just idled a lot right before draining the oil?

 

[shortyb]

Typical Blackstone fuel numbers, they are either all over the place or always under ".5%". I bet if you had a proper GC fuel dilution test done, it would be between 2-3%. Still, oil did it's job. It stayed in grade and wear metals are low for an almost 5K interval in a forced induction engine. Motor on.

 

[Tier1Terrier]

Happy to see all these responses. What would be a better alternative to Blackstone for a used oil analysis report?

 

[Oliveoil2]

Probably due to colder weather, and/or increased idling? Really looks like a non issue if you look at the numbers.

 

[shortyb]

Happy to see all these responses. What would be a better alternative to Blackstone for a used oil analysis report?

Try these folks.
https://www.oaitesting.com/

 

[fantastic]

What the others mentioned...dump BS if you want to accurately measure fuel in your oil via GC method but you want to make sure to specifically request it.

 

[930.engineering]

Still, oil did it's job. It stayed in grade and wear metals are low for an almost 5K interval in a forced induction engine.

I agree, that oil did its job since wear metals are low. Nevertheless
M1 FS 5W-50 doesn't stay in grade (again). Min 16.3 cSt vs 13,6 cSt
provided we'd believe BS or even if we don't trust BS. That difference
is huge.
.

 

[chris719]

The ESP X3 comes out at almost the same KV100 as this. The FS oils for sure seem to drop quite a bit.

 

[buster]

I still struggle with the idea of 0w/5w-50. Even the Mobil 1 Racing 0w50 which is highly regarded in racing, only has a HT/HS of 3.9, by design. Just seems odd to design an oil that inevitably drops down to a 40 grade in service. But we know Mobil has a ton of testing data from their own testing and from all the teams using their oils.

https://www.mobil.com/en/lubricants/for-personal-vehicles/our-products/products/mobil-1-racing-0w-50

 

[chris719]

I still struggle with the idea of 0w/5w-50. Even the Mobil 1 Racing 0w50 which is highly regarded in racing, only has a HT/HS of 3.9, by design. Just seems odd to design an oil that inevitably drops down to a 40 grade in service. But we know Mobil has a ton of testing data from their own testing and from all the teams using their oils.

https://www.mobil.com/en/lubricants/for-personal-vehicles/our-products/products/mobil-1-racing-0w-50

The Motul 300V or Red Line make more sense to me, having a 5.0 HTHS.

 

[OVERKILL]

I agree, that oil did its job since wear metals are low. Nevertheless
M1 FS 5W-50 doesn't stay in grade (again). Min 16.3 cSt vs 13,6 cSt
provided we'd believe BS or even if we don't trust BS. That difference
is huge.
.

There's definitely fuel pushing down that visc with the 355F flashpoint.

 

[Geoff]

If you had your foot in it near full throttle, it will run rich on boost to protect against detonation. Typical for any forced induction engine. Cold weather and idling like what the other guys said. Original air filter?