Motul Xcess 8100 5w40, 5437km OCI, 2010 STI

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First UOA on this vehicle, oil looks fine but iron levels. Any tips on things to look into?

No longer my daily driver, will probably only see a couple thousand kms/year here on out. No track/racing but some spirited driving and WOT here and there.
The first 50,000kms were short city trips and lots of stop and go driving. Maybe some wear attributed to that? Nowadays she gets some more highway driving.

Some bolt on upgrades (Cobb: downpipe, exhaust, intake, tuner) running OTS map.

 
I once owned an 07' WRX with the 2.5L engine and posted a UOA on here years ago. That much Iron is not typical in any WRX, regardless of the year or if it's an STi or not. I would definitely do another UOA. BTW, I had a stage II Cobb tune with a Perrin catted downpipe. I switched to the Perrin map that came with the downpipe. The Perrin map was a lot better feeling than the Cobb stage II map. I doubt your driving contributed to the high Iron.
https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/2926183/1
 
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It's your first report so you are going to need to establish a baseline. The high iron right off the bat is a bit concerning; I don't think short-tripping would have contributed to that. What was the car's history earlier in its life? (oil type/interval, driving habits, climate, etc)

Also, is the car spec'd for 5w40?
 
I'd change the tune before anything else.

Cobb OTS tunes are terrible in my experience. Lean spots all over the midrange and PIG rich when it goes open loop under heavy boost. I have a wideband 02 sensor in my DP and observed afrs UNDER 10:1 at full boost on the OTS mapping back when I first had the stage 2 setup on my WRX.

If there is an experienced tuner anywhere even remotely near you it would definitely be worth your time and money to get a proper tune.
 
Originally Posted By: dparm
It's your first report so you are going to need to establish a baseline. The high iron right off the bat is a bit concerning; I don't think short-tripping would have contributed to that. What was the car's history earlier in its life? (oil type/interval, driving habits, climate, etc)

Also, is the car spec'd for 5w40?


Pretty short OCI's of 4,000 - 6,000 kms (2,500 - 3,750 miles), started on conventional, then switched to synthetic 5w30 while subaru did service for warranty. Once out of warranty on Rotella T6 5w40 or Motul Xcess 8100 5w40. Like I said I used to live in downtown so lots of stop and go trips 5-10km. A few 1,200km road trips. Starts anywhere from -30 to +30 celcius. I can't think of a time where it would see super stressful conditions. Oil recommendations are in the pic below, pretty much says anything from 5w30 to 10w50 depending on climate.

I know the Cobb OTS maps aren't perfect, would running rich or lean fuel be contributing to iron in the oil? I thought if anything if it was running rich I would be seeing fuel in the oil, but there was none. I asked for a custom tune about 25,000kms ago when I had all the Cobb stuff installed, they told me not to worry about it until I started changing internals.

 
As mentioned, elevated iron isn't a typical trait of WRX's and STI's and I wouldn't be too concerned at this point with only one uoa. This is a good thread about high iron numbers in uoa's:

https://bobistheoilguy.com/forums/ubbthreads.php/topics/2089130/1

And a good article about uoa's in general.

https://bobistheoilguy.com/used-oil-analysis/

As for the tune, I think it can go either way. I believe Cobb OTS tunes may be hit or miss over the years depending on the model and year but I've been on an OTS tune for nearly 60k miles and haven't had any concerns. Even when I was running a bit rich, fuel dilution would typically increase although there were no elevated wear metals. Since your annual mileage is so low it's going to be a while before you establish a trend. If you're really concerned look into a Dyson Analysis.
 
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