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2020 Subaru Outback 2.4l Turbo, Mobil 1 T-SUV 5w-30/AFE 0w-20 Blend, 3300 mile OCI, Copper Increase, OAI vs. Blackstone
- Thread starter Jack_Kieran
- Start date
Comments on my UOAs posted above:
UOA by OAI shows INCREASE in Copper level. What level concern should I have? Suggested course of action?
Lab error can be ruled out, as I had retained more of drain sample and sent it to Blackstone for comparison, and they got similar Copper result.
OAI also showed slight increase in Lead and Sodium values, but they did not flag as abnormal. Blackstone did not show any Lead, and a much smaller Sodium value.
Previous interval showed normal value of Copper after steady decreases in successive checks, as expected, as this vehicle with still fairly-low 18,000 miles went thru break-in.
Oil used in latest interval (OAI #5 sample) was same blend of Mobil 1 type/ viscosities (albeit from different jugs) as in OAI #4 sample: 63% Truck & SUV 5w-30 plus 37% AFE 0w-20. Interval 4 used Napa Gold 7055 filter, interval 5 used Fram Ultra XG7317.
Interval 5 had 50% more miles (3300 vs. 2200), 8 month time interval vs. 2 months, and a greater proportion of shorter trips.
I did start using Union 76 gas in latest interval in addition to the previous typical Costco, Chevron, Shell. Always 92 octane premium.
On a positive note, this oil blend held its viscosity very well in both intervals, dropping from a calculated kV100 of 9.3 when new to 8.5 after use. This despite the fuel dilution of 2.5% which is typical for this GDI turbo engine.
UOA by OAI shows INCREASE in Copper level. What level concern should I have? Suggested course of action?
Lab error can be ruled out, as I had retained more of drain sample and sent it to Blackstone for comparison, and they got similar Copper result.
OAI also showed slight increase in Lead and Sodium values, but they did not flag as abnormal. Blackstone did not show any Lead, and a much smaller Sodium value.
Previous interval showed normal value of Copper after steady decreases in successive checks, as expected, as this vehicle with still fairly-low 18,000 miles went thru break-in.
Oil used in latest interval (OAI #5 sample) was same blend of Mobil 1 type/ viscosities (albeit from different jugs) as in OAI #4 sample: 63% Truck & SUV 5w-30 plus 37% AFE 0w-20. Interval 4 used Napa Gold 7055 filter, interval 5 used Fram Ultra XG7317.
Interval 5 had 50% more miles (3300 vs. 2200), 8 month time interval vs. 2 months, and a greater proportion of shorter trips.
I did start using Union 76 gas in latest interval in addition to the previous typical Costco, Chevron, Shell. Always 92 octane premium.
On a positive note, this oil blend held its viscosity very well in both intervals, dropping from a calculated kV100 of 9.3 when new to 8.5 after use. This despite the fuel dilution of 2.5% which is typical for this GDI turbo engine.
On the one hand, this vehicle has less than 19k miles on it, so it could easily be break-in still washing out. On the other hand, there have been 5 oil changes, so you'd think it all would've washed out by now. I've seen results where the break-in doesn't end til >25k miles, so I'd suggest wait til at least then before you draw any conclusions.
Thanks for another data point on gas chromatography vs fuel estimation. <0.5% vs 2.5%.
Thanks for another data point on gas chromatography vs fuel estimation. <0.5% vs 2.5%.
All of the Subaru 2.4Ts have oil coolers, so copper in these is generally NOT from bearings. At less than 20k miles, this is likely still normalizing even though it went up some here.
From what I have seen in the FA20DIT (old uoa's on nasioc), there was not much difference in the rate that break-in wear washed out in 3k mile or 5/6k mile OCI's.
The Si in my XT was 28 at 24,257 miles and 21 at 28,743 miles using paper filters and ~4,500 OCI's. Cu was 14 and 7. Si seems to take a while to wash out and hopefully your Cu will drop. Odd that it shot up but maybe it's just noise/oil cooler/slow break-in/etc.
The Si in my XT was 28 at 24,257 miles and 21 at 28,743 miles using paper filters and ~4,500 OCI's. Cu was 14 and 7. Si seems to take a while to wash out and hopefully your Cu will drop. Odd that it shot up but maybe it's just noise/oil cooler/slow break-in/etc.
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Copper leaches from the oil cooler, probably through a corrosion process. To a certain extent it probably happens even when the engine isn't running, but faster in warmer weather, and much faster when the engine is running. Assuming copper corrosion increases with time, temperature, and mileage, these results seem pretty reasonable.
1.5 months: 15 ppm Cu
6 months, over winter: 35 ppm
7 months, summer to winter, with 50% more miles on OCI: 57 ppm
If you had 20+ ppm copper from bearings, I think you'd see more of other metals like lead, tin, and aluminum. Lead is a touch high at 3 ppm on the OAI test, but 0 ppm with Blackstone. I wouldn't worry about it.
1.5 months: 15 ppm Cu
6 months, over winter: 35 ppm
7 months, summer to winter, with 50% more miles on OCI: 57 ppm
If you had 20+ ppm copper from bearings, I think you'd see more of other metals like lead, tin, and aluminum. Lead is a touch high at 3 ppm on the OAI test, but 0 ppm with Blackstone. I wouldn't worry about it.
Good observation about the time-related component for copper pickup in oil, I hadn't considered that. It does seem to fit my most recent results. Also explains BlueSubie's general observation that shorter vs. longer OCIs don't seem to affect how long in total miles it takes for break-in related Cu washout to fully complete. Results of next UOA will be interesting.
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