Car: 2011 Subaru WRX Hatch
Total Miles: 15,174
Miles on Oil: 3,556
Oil: 5W-30 Castrol Edge Syntec (2011 black bottle)
Makeup Oil: 0 quarts
Filter: OEM Blue Subaru Filter
Driving Conditions: 90% highway at 65-70 mph. Occasional revs to 4000, 5000 RPM.
Comments:
I think I'll continue with 3750 mi oil change intervals. I could go to 5000 mi, but Syntec would probably shear to 8.X cSt by that point. But if wear continues to decrease, I don't see the problem. Thoughts?

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OIL 5W-30 Castrol 5W-30 Castrol 5W-30 Castrol Subaru 5W-30 Factory Fill Edge Syntec Edge Syntec Edge Titanium (Idemitsu Lubricants) MILES IN USE 3556 3296 3182 5135 MILES 15174 11618 8317 5135 SAMPLE TAKEN 02/04/12 12/10/11 10/21/11 09/09/2011 MAKE UP OIL 0 qts 0 qts 0 qts 0 qts ALUMINUM 5 5 7 - CHROMIUM 1 1 1 0 IRON 6 10 11 22 COPPER 4 6 12 34 LEAD 0 0 0 1 TIN 0 2 4 1 MOLYBDENUM 77 191 260 976 NICKEL 2 1 2 2 MANGANESE 0 0 1 3 SILVER 1 1 0 0 TITANIUM 1 6 38 0 POTASSIUM 1 0 2 0 BORON 42 97 61 166 SILICON 5 8 18 79 SODIUM 2 1 3 9 CALCIUM 732 975 954 1854 MAGNESIUM 1544 1296 1223 11 PHOSPHORUS 702 753 766 838 ZINC 771 1084 882 1028 BARIUM 0 0 0 2 INSOLUBLES (%) 0.2 0.1 0.2 0.2 WATER (%) 0.0 0.0 0.0 0.0 ANTIFREEZE (%) 0.0 0.0 0.0 0.0 FUEL (%) <0.5 <0.5 TR <0.5 FLASHPOINT ºF 390 400 360 390 SUS VIS 210ºF 58.3 56.5 56.4 52.6 cSt @ 100ºC 9.72 9.22 9.17 8.06 TBN 7.1 7.6 6.7 3.5
