Mobil1 0w-40 FS, 18576km in SAAB B258/Opel C25XE

Messages
305
Location
Germany
Second OCI after purchase. First OCI can be found here.
This was supposed to be a short OCI. Yeah. Did not work out quite so well. Nearly 15 months and roughly 18,500km/11,500 miles.

The numbers:

OIL Mobil1 0w-40 FS
MILES IN USE 11545 (18576km), ~15 months
MILES 156659 (252065km)
SAMPLE TAKEN 01/25/20 (date format for the civilized part of the world: 25.01.2020)
FILTER: SAAB M94-V6 4502696 (pictures to follow)

wear metals (mg/kg)
IRON 26
CHROME 2
TIN 0
ALUMINUM 3
NICKEL 0
COPPER 8
LEAD 0
MANGANESE 0
pq-index <25

pollution (mg/kg)
SILICON 10
POTASSIUM 0
SODIUM 6
WATER (%) <0.10
IR-GLYKOL negative
FUEL (%) 0,9

Additives (mg/kg)
CALCIUM 3111
MAGNESIUM 23
BORON 152
ZINC 1089
PHOSPHORUS 877
BARIUM 0
MOLYBDENUM 79
SULPHUR 2111

state of oil:
visc. @40°C (mm2/s) 79.58
visc. @100°C (mm2/s) 13.78
VI 179
OXYDATION (A/cm) 12
NITRATION (A/cm) 7
SULFATION (A/cm) 2
Dispergency* (%) 90
SOOT INDEX** 0.2
TBN: 8.79

* the german word was "Schmutztragevermögen", hope I translated that right. **
the lab has introduced the "Rußindex", an in-house tool to check for soot in gasoline oil, as soot from direct-injection engines will not show correctly in the standard test for diesel oils

252k_uoa_werte.JPG



Wear metals didn't change, even though the distanceand time was greatly increased. The oil itselfdoes not only have more additives, it also seems to have held up better than the Shell HX7 that was in there in the previous OCI. After all, oxydation and nitration are not worse even after a greatly extended OCI, and sulfation is much lower. However, the previously used Shell was at a disadvantage: During the M1's OCI, I had the valve cover gaskets redone. This seems to have brought down water/moisture. Also, the car got a new exhaust, and probably because of that, fuel dilution was also lower, even though the driving profile did not change much. I have the impression that this might have helped a bit with chemical stability.

Also, I have the impression that this engine is slowly clearing out. The previous owners had severely short tripped the car, combined with less than ideal oil change intervals (quite conservative by milage, rather outrageous by time).
The car is now reacting much livelier to throttle input, oil consumption is reduced, and fuel efficiency has improved. I am inclined to believe that the rings are now freed up, but the fuel efficiency improvement might be influenced also by driver input, as 1) both of us got to know the car better and 2) wife has now much more driving experience (this is her first car!)

So, what does this tell us? Probably to keep your house in order. Fix small issues before they become big. If the engine is running in perfect condition, oil will age slower. Also, the C25XE (GM 54°V6) seems not to be too hard on oil. And M1 FS also looks like a great oil.


Blog post (german): https://turboseize.wordpress.com/20...w-40-fs-nach-18576km-im-saab-b258-opel-c25xe/
 
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Messages
25,807
Location
MA, Mittelfranken.de
The engine seems to like that oil, I would stick with it. Like most Saab/Opel engines check the PCV system for proper function, they have a habit of varnishing due to poor PCV systems.
 

turboseize

Thread starter
Messages
305
Location
Germany
Pictures of the filter for the 18.5Mm-Interval can be found here:



I just got the UOA from the last interval (14Mm) back. Looks even better, will post soon.
 
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Messages
3,444
Location
Austin, TX MSA
SAMPLE TAKEN 01/25/20 (date format for the civilized part of the world: 25.01.2020)

I don't think that implying MMDDYYYY date format as belonging to an uncivilized part of the world is particularly endearing to the American members of this forum, who I would say comprise the overwhelming majority of the membership. There are many countries that are decidedly uncivilized that use the DDMMYYYY format, Germany of course not being one of those uncivilized countries, but many examples exist. My wife for example is from Brazil and they use the DDMMYYYY format, but most of that country is decidedly un-civilized as per my personal observations with the exception of the central portions of a few large cities and some tourist destinations.

Moving along...

Your oil analysis looks excellent and I would keep doing the same regimen. The only thing I would question is the TBN of 8.79, that seems really high after more than 18,000 km.
 

turboseize

Thread starter
Messages
305
Location
Germany
I don't think that implying MMDDYYYY date format as belonging to an uncivilized part of the world is particularly endearing to the American members of this forum, who I would say comprise the overwhelming majority of the membership. There are many countries that are decidedly uncivilized that use the DDMMYYYY format, Germany of course not being one of those uncivilized countries, but many examples exist.
Well, the format is just weird and unlogical. Just as imperial measurement units. These are just backwards. The whole world agrees on this - except Liberia, Myanmar and the United States...*
And don't be so sure about Germany being non-uncivilised: we, too, can be quite barbaric. We have no speed limit and we eat raw pork!;)
Back to topic.

Your oil analysis looks excellent and I would keep doing the same regimen. The only thing I would question is the TBN of 8.79, that seems really high after more than 18,000 km.
Maybe a lab artefact, maybe it's the fuel quality. Europe has had ultra-low sulphur fuel for ages now. There have been the same questions regarding TBN when I posted UAOs from my other SAAB. After 10,000km, TBN was still close to 10 with both M1 New Life and Shell Helix Ultra 0w-40. When i ran the Shell HU 0w-30 AV-L (a low-SAPS C3) in my turbo, TBN was 4.42 after 19,000km (starting around only eight point something, if I remember correctly), with AN already up to 4.33...

*Actually, the US has adopted the metric system. Kind of. It signed the convention... but you citizens are withheld the benefits of SI units. So sad!
(But then there are a lot of other things you DO get right. The value of individual freedom for example... Europe always has a tendency to value the individual far less than "the greater good". Please be vigilant, do not fall into the same trap.)
 
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Messages
1,295
Location
Brittany / Canada
I would too "blame" the ultra low sulphur and general quality of gas in Europe (maybe not everywhere in Europe, but obviously Germany).

I too had UOA with TBN around 10, from oils that should start slightly above that...in cars with suggested OCi of 20000Km 😁...where I wasted oil by doing short OCI.
 
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Messages
66
Location
TX
Well, the format is just weird and unlogical. Just as imperial measurement units. These are just backwards. The whole world agrees on this - except Liberia, Myanmar and the United States...*
And don't be so sure about Germany being non-uncivilised: we, too, can be quite barbaric. We have no speed limit and we eat raw pork!;)
Back to topic.


Maybe a lab artefact, maybe it's the fuel quality. Europe has had ultra-low sulphur fuel for ages now. There have been the same questions regarding TBN when I posted UAOs from my other SAAB. After 10,000km, TBN was still close to 10 with both M1 New Life and Shell Helix Ultra 0w-40. When i ran the Shell HU 0w-30 AV-L (a low-SAPS C3) in my turbo, TBN was 4.42 after 19,000km (starting around only eight point something, if I remember correctly), with AN already up to 4.33...

*Actually, the US has adopted the metric system. Kind of. It signed the convention... but you citizens are withheld the benefits of SI units. So sad!
(But then there are a lot of other things you DO get right. The value of individual freedom for example... Europe always has a tendency to value the individual far less than "the greater good". Please be vigilant, do not fall into the same trap.)


Well the 'best' date format is what Japan uses - YY/MM/DD. Makes storing files much easier ;)

Back to subject - How is the 100C vis so high? My US spec sheet shows 12.9 while the analysis shows 13.78. Maybe the European oil is different than the US one.
 
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