Any thoughts on this UOA?
2012 Subaru Legacy GT (EJ255 , low-mount turbo)
About 50/50 city, highway. All mileage numbers are in kilometers.
This is 0w-40 Belgian Castrol A3/B4. No oil consumption. Subaru blue filter. Previous UOA were on subsequent changes. The previous fill was with Shell Rotella T6 0w-40 , before that it was Subaru (Idemitsu) 5w-30 synthetic.
I made no mechanical changes to the motor over this time, however I did replace the OEM turbo bypass valve with an aftermarket (full recirculating) one, that is made of what looked like aluminum alloys. I would expect it to have shed some wear metals possibly.
Magnesium coming from the oil itself? I've seen high magnesium in German Castrol as well, so just asking.
I extract my samples good and hot using a vacuum pump via the dipstick tube.
I have heard, anecdotally, that Subaru turbo motors tend to get random spikes of copper resulting from oxidation in the oil cooler. What I am wondering, is if my increased Tin level (from 0 to 5 ppm) is significant enough to signal something other than just oil cooler oxidation.
Thanks for any input
2012 Subaru Legacy GT (EJ255 , low-mount turbo)
About 50/50 city, highway. All mileage numbers are in kilometers.
This is 0w-40 Belgian Castrol A3/B4. No oil consumption. Subaru blue filter. Previous UOA were on subsequent changes. The previous fill was with Shell Rotella T6 0w-40 , before that it was Subaru (Idemitsu) 5w-30 synthetic.
I made no mechanical changes to the motor over this time, however I did replace the OEM turbo bypass valve with an aftermarket (full recirculating) one, that is made of what looked like aluminum alloys. I would expect it to have shed some wear metals possibly.
Magnesium coming from the oil itself? I've seen high magnesium in German Castrol as well, so just asking.
I extract my samples good and hot using a vacuum pump via the dipstick tube.
I have heard, anecdotally, that Subaru turbo motors tend to get random spikes of copper resulting from oxidation in the oil cooler. What I am wondering, is if my increased Tin level (from 0 to 5 ppm) is significant enough to signal something other than just oil cooler oxidation.
Thanks for any input
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