The original posting on the RLI Super High Performance Bio-Synthetic 5W40 HD oil is here:
]Double-Super-Secret 5W-40 Audi RS4 Racing Oil
Since then, quite a large number of UOAs have been performed, 80 UOAs, 20 RS4 engine, 610 to 53500 miles, 17 different Audi/VW 502/505 oils.
Here is a normalized Fe wear plot comparing Biosyn to other Audi approved oils. The last blue point and the last green point, at 38000 and 53000 miles respectively, were UOA samples taken on the same engine with Castrol TXT 5W40 and RLI Biosyn 5W40.
I'll let you all form your own conclusions.
measurement (Castrol TXT 5W40/RLI Biosyn 5W40)
miles on engine (38040/53500)
miles on oil (6000/10000)
Fe (33/26)
Sn (0/0)
Pb (2/3)
Cr (1/1)
Ni (1/1)
Al (10/10)
Si (6/6)
Na (15/10
100 cSt (10.7/12.2)
TAN (2.75/4.02)
Flash (305/250)
Nitration (12/13)
TBN (3.9/3.8)
VI (151/159)
]Double-Super-Secret 5W-40 Audi RS4 Racing Oil
Since then, quite a large number of UOAs have been performed, 80 UOAs, 20 RS4 engine, 610 to 53500 miles, 17 different Audi/VW 502/505 oils.
Here is a normalized Fe wear plot comparing Biosyn to other Audi approved oils. The last blue point and the last green point, at 38000 and 53000 miles respectively, were UOA samples taken on the same engine with Castrol TXT 5W40 and RLI Biosyn 5W40.
I'll let you all form your own conclusions.
measurement (Castrol TXT 5W40/RLI Biosyn 5W40)
miles on engine (38040/53500)
miles on oil (6000/10000)
Fe (33/26)
Sn (0/0)
Pb (2/3)
Cr (1/1)
Ni (1/1)
Al (10/10)
Si (6/6)
Na (15/10
100 cSt (10.7/12.2)
TAN (2.75/4.02)
Flash (305/250)
Nitration (12/13)
TBN (3.9/3.8)
VI (151/159)
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