I have a 2005 Subaru Forester XT. Relatively new to me, I bought it at 156K last year. Been through two OCIs since I've owned it. Both went to Blackstone. I've had high chromium and they flagged the sodium this time. The engine seems fine, no unexplained coolant loss, knocks or CELs indicating problems. Compression was OK at the time of purchase but I haven't checked since then. Will probably do so soon at Blackstone's advice. I've exchanged emails with them and they suggested that along with checking the cylinder walls with a borescope. They said they weren't entirely sure about coolant making it into the oil since my potassium is 0, but it seemed like a likely culprit for the sodium at Shell doesn't use it in RT6. The previous owners used Mobile 1 and Castrol 5W-30 so I'm hoping that it's just leftovers from that instead. I doubt it would have flushed out entirely after just two changes. I've only been using the the Rotella T6.
This car is mostly a town/rural road driver with very few highway miles with me. Lots of stop and go with a ~10 mile one way commute. I've done some lurking on here and it seems some people recommend a thinner oil than a 5W-40 in for that type of use. Thoughts? Perhaps that would cut down on some of the wear? Prep for a rebuild sooner rather than later?
Hopefully this is formatted neatly enough. This is my first post!
Code:
MI/HR on Oil 3698 3572
MI/HR on Unit 159847 163420
Sample Date 10/17/14 05/22/15
Oil Added (qts) 0.75 0.875
Oil Type RT6 5W-40 RT6 5W-40
Filter Type NAPA Gold NAPA Gold
ALUMINUM 3 3
CHROMIUM 4 5
IRON 10 14
COPPER 5 3
LEAD 1 1
TIN 0 0
MOLYBDENUM 64 63
NICKEL 1 1
MANGANESE 0 1
SILVER 0 0
TITANIUM 0 0
POTASSIUM 0 0
BORON 36 33
SILICON 9 9
SODIUM 45 47
CALCIUM 926 856
MAGNESIUM 1273 1268
PHOSPHORUS 1052 1036
ZINC 1266 1274
BARIUM 0 0
SUS Viscosity @ 210°F 71.3 68.1
cSt Viscosity @ 100°C 13.3 12.45
Flashpoint in °F 385 385
Fuel %
Antifreeze % ? 0
Water % 0 0
Insolubles % 0.3 0.4
This car is mostly a town/rural road driver with very few highway miles with me. Lots of stop and go with a ~10 mile one way commute. I've done some lurking on here and it seems some people recommend a thinner oil than a 5W-40 in for that type of use. Thoughts? Perhaps that would cut down on some of the wear? Prep for a rebuild sooner rather than later?
Hopefully this is formatted neatly enough. This is my first post!
Code:
MI/HR on Oil 3698 3572
MI/HR on Unit 159847 163420
Sample Date 10/17/14 05/22/15
Oil Added (qts) 0.75 0.875
Oil Type RT6 5W-40 RT6 5W-40
Filter Type NAPA Gold NAPA Gold
ALUMINUM 3 3
CHROMIUM 4 5
IRON 10 14
COPPER 5 3
LEAD 1 1
TIN 0 0
MOLYBDENUM 64 63
NICKEL 1 1
MANGANESE 0 1
SILVER 0 0
TITANIUM 0 0
POTASSIUM 0 0
BORON 36 33
SILICON 9 9
SODIUM 45 47
CALCIUM 926 856
MAGNESIUM 1273 1268
PHOSPHORUS 1052 1036
ZINC 1266 1274
BARIUM 0 0
SUS Viscosity @ 210°F 71.3 68.1
cSt Viscosity @ 100°C 13.3 12.45
Flashpoint in °F 385 385
Fuel %
Antifreeze % ? 0
Water % 0 0
Insolubles % 0.3 0.4