Just got a UOA done on my 2011 WRX. This run was Subaru synthetic 5w30, which is what I've used since the car was new. I used to be able to get a really good deal on this oil, but not anymore, so I figured I'd stop running it and get one last UOA for comparison to the next run (which is PU 5w30).
Blackstone's comments mentioned that the new UOA was of a different oil from the first couple -- presumably due to the large differences in moly, calcium, and boron. I guess this points to a reformulation of the Subaru branded oil. The earlier samples were probably SM so perhaps there were changes related moving the oil to SN.
The viscosity drop on the first two samples actually seemed pretty good for an RC 5w30 but the last run didn't do as well. Makes me glad I'm switching and I will look forward to seeing how the PU holds up.
Code:
MI/HR on Oil 5,141 5,270 5,221
MI/HR on Unit 70,109 25,906 15,628
Sample Date 3/12/2016 3/9/2013 6/30/2012
Make Up Oil Added 1 qt 1 qt 0.5 qt
ALUMINUM 6 3 3
CHROMIUM 0 1 1
IRON 5 7 8
COPPER 1 3 5
LEAD 0 0 0
TIN 3 1 0
MOLYBDENUM 150 55 56
NICKEL 1 1 1
MANGANESE 0 0 0
SILVER 1 0 0
TITANIUM 0 0 0
POTASSIUM 0 1 0
BORON 52 3 2
SILICON 8 4 7
SODIUM 4 5 4
CALCIUM 1914 2572 2934
MAGNESIUM 0 14 23
PHOSPHORUS 613 710 814
ZINC 762 850 1003
BARIUM 0 0 0
SUS Viscosity @ 210°F 54.2 60.80 59.00
cSt Viscosity @ 100°C 8.55 10.45 9.94
Flashpoint in °F 390 405 400
Fuel %
Antifreeze % 0.0 0.0 0.0
Water % 0.0 0.0 0.0
Insolubles % 0.2 0.2 0.3
TBN --- 2.8 3.5
Blackstone's comments mentioned that the new UOA was of a different oil from the first couple -- presumably due to the large differences in moly, calcium, and boron. I guess this points to a reformulation of the Subaru branded oil. The earlier samples were probably SM so perhaps there were changes related moving the oil to SN.
The viscosity drop on the first two samples actually seemed pretty good for an RC 5w30 but the last run didn't do as well. Makes me glad I'm switching and I will look forward to seeing how the PU holds up.
Code:
MI/HR on Oil 5,141 5,270 5,221
MI/HR on Unit 70,109 25,906 15,628
Sample Date 3/12/2016 3/9/2013 6/30/2012
Make Up Oil Added 1 qt 1 qt 0.5 qt
ALUMINUM 6 3 3
CHROMIUM 0 1 1
IRON 5 7 8
COPPER 1 3 5
LEAD 0 0 0
TIN 3 1 0
MOLYBDENUM 150 55 56
NICKEL 1 1 1
MANGANESE 0 0 0
SILVER 1 0 0
TITANIUM 0 0 0
POTASSIUM 0 1 0
BORON 52 3 2
SILICON 8 4 7
SODIUM 4 5 4
CALCIUM 1914 2572 2934
MAGNESIUM 0 14 23
PHOSPHORUS 613 710 814
ZINC 762 850 1003
BARIUM 0 0 0
SUS Viscosity @ 210°F 54.2 60.80 59.00
cSt Viscosity @ 100°C 8.55 10.45 9.94
Flashpoint in °F 390 405 400
Fuel %
Antifreeze % 0.0 0.0 0.0
Water % 0.0 0.0 0.0
Insolubles % 0.2 0.2 0.3
TBN --- 2.8 3.5