The next uoa. (Last one can be seen here
Saab 900 turbo 17, model year 1985. Engine code B202L. Total mileage 572233km, which equals 355645 miles. Engine rebuild at 410000km/254700mi due to defective LH-jet (did not enrich enough under full boost and killed a piston ring).
OIL Aral Super Tronic 0w-40
MILES IN USE 6558 (10552km), 3 months
MILES 355645 (572233km)
SAMPLE TAKEN 16/03/08
wear metals (mg/kg)
WATER (%) <0.1
FUEL (%) 1.03
state of oil:
visc. @40°C (mm2/s) 73.5
visc. @100°C (mm2/s) 12.91
OXYDATION (A/cm) 7
NITRATION (A/cm) 2
SULFATION (A/cm) 0
dispergency* (%) 93
SOOT INDEX** <0.1
* 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
Here is the original:
I wrote a short article on my blog:https://turboseize.wordpress.com/2016/03...00-turbo-b202l/
(It's in german, but perhaps google translate might help. Ift not, feel free to ask me any questions...)
Thi soil is my mechanic's standard choicem because ist vollsynthetisch
(all PAO) and relatively cheap. Yes, it's a low-SAPS oil, and the old B202, being an indirect-injection petrol engine does not have (nor need) a particel filter, so a low-SAPS oil might seem useless.
On the other hand, both 229.51 and 229.5 have the same requirements regarding wear and engine cleanliness. The oil also sports a Porsche A40, which is important because this certification includes testing in a turbocharged engine, that gets switched off repeatedly directly after heavy use - this is to test the oils resistancy to coking. Early Saab 202 (and b201) are fitted with Garret T3 turbos, which are, unlike many modern turbos, NOT water-cooled. So resistance to coking is an issue in these engines.
Our hypothesis was: "there is no significant difference between any oils certified 229.5 or 229.51". Yes, iron is a bit higher than with the previous Mobil1 "new life", but if you factor in the different mileages on the oil and equalize them to 10,000km, you get ~13 for the Mobil1 and ~16 for the Aral. Now think about the margin of error of the analysis, and this is next to nothing.
Next two intervals will be driven with Shell Helix Ultra 0w-40. I was originally planning to test a cheap hydrocracked 5w-40 (in keeping with our mantra MB 229.5 is everything), such as Addinol 0540 or Total Quartz 9000 energy, which both can be had for around 18€/5liters. But then I got a great deal for the Shell: 20€ /5liters is a great price for a 0w-40 (Compare that to Mobil1 new life which costs at least 32€).