Motul 8100 5w40, 5,500 miles, 2002 WRX (stg 4/18G)

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Did another interval with Motul 8100 X-cess, though shorter than last time (5,500 vs 9,000). Iron is still a bit high. Switched from a K&N air filter to OEM paper and silicon dropped by half.

I poured Rotella T6 5w40 in there this time (actually just 4 qts of it, along with a qt of GC 0w30... didn't notice the T6 comes in 4qt jugs instead of 5qt so had to raid my cabinet... d'oh). We'll see how that goes.

UOA thread from my prior Motul change: BITOG

WRX%2BOIL%2B115K.jpg
 
Forgot to say, The car saw routine but spirited action this time (and only 5,500 miles in 16 months) with predominantly city/short range trips, but in the intense Arizona heat. It did one track day, but my wife was driving it and taking it easy.
 
Thanks for the reply, Ted.

Just a few thoughts:

Isn't the recommended OCI on these @ 3,750 now? Based on wear rates, I see no reason to try extended OCI's at this juncture.

As well, even in the Arizona heat, the best results you've achieved to date has been with a 30 weight product - telling.

Heck, given the oil capacity and minimal usage, I'd be very inclined to pick up a 5 qt. jug of inexpensive, shear stable 10w-30 at WalMart (along with the corresponding filter) and forget about the specialty, higher-dollar stuff.
 
So the trick is that there isn't really such a thing as a sheer-stable normal 30-wt oil for the Subaru EJ 2.0 turbo engines, especially highly modified ones... they are notorious for shearing 30-wt oil to 20wt in just a few hundred miles, which has caused a multitude of spun bearings and massive engine damage. So I will never ever put another 30wt oil in my car ever again EXCEPT GC, which is labeled a 30wt but is really a 40 wt and has shown to have outstanding sheer stability in this engine.

IMO, following OCI specs for anything in a car making ~350 hp compared to 225 hp stock is a bad idea. It's really about the data from my gauges (which aren't in the UOA of course) and from the UOAs. And my gauges tell me that when running 115mph around the banking of Pocono my oil temp is 10-degrees C cooler with a fancy racing oil. And to my eyes, based on wear rates, there is no reason NOT to use long oil change intervals -- the viscosity and TBN numbers indicate it's possible to run 9,000 miles very safely.

That said, I do agree the GC data indicates it works very nicely and I may very well switch back to it (I was switching between Redline and GC for 50K miles before I moved to AZ and my excellent engine tuner put Motul in my car). But many, many WRX owners have had success with T6, so I thought I'd give it a try this time around (actually, my current fill is 4 qts T6 and one of GC, so I'm already tip-toeing back). We'll see...
 
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-16ppm iron @ 5,300 miles isn't my idea of a successful extended OCI in this application, especially considering your cost. TBN, viscosity, and whatever other metrics you want to throw out are meaningless if you can't satisfactorily control wear.

-Shear stable 10w-30's (that, barring fuel contamination, will stay in grade) do exist, and they're available locally. It only took me a few minutes to find results on NASIOC showing pedestrian 10w-30's holding viscosity in modified EJ205's and delivering better UOA results than what you've been able to accomplish.

At the end of the day, it's yours, and you can do as you please. Good luck.
 
You 'could' purchase a Klennoil bypass filter if you have a fuel dilution problem. It obsorbs/adsorbs water and fuel.
 
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Regarding the OCI, SoA does recommend 3,750 miles on all pre-2011 turbos but that's only because of the AVCS and turbo banjo bolt screen clogging issues on the later MY 2.5 turbos (and subsequent turbo failures).

You MIGHT be ok on a Wal-Mart 10W-30, but there's no need to experiment giving your application, IMO. Unless, of course, Ramblejam provides you with some kind of warranty.
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Ed Hackett on here does have some good uoa's on RT5 in a stock, non-tracked '08-ish? Legacy GT but HDEO's are different.

Nice drop in silicon!
thumbsup2.gif


-Dennis
 
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I've never had more than a trace of fuel. My UOAs have always been exceptionally free of fluid contamination (knock wood).
 
Technically, I'm on Wal-Mart oil right now, since that's where I got my T6. But yeah, the overwhelming consensus I've seen among Subie tuners and race mechanics and enthusiasts and the related UOAs is to use a good quality synth 40 wt oil. And when I just went over to NASIOC to look for the rumored "good" 30-wt UOAs, the first three I found all had sheared to 20-wt. So no thanks on that... I still want to be able to track the car on a moment's notice, I've just been using my new toy for the last few I've done.

That said, I won't be using the Motul again. If the T6 doesn't work as hoped, I'll go back to GC and/or perhaps the Redline.


Originally Posted By: bluesubie
01.gif


Regarding the OCI, SoA does recommend 3,750 miles on all pre-2011 turbos but that's only because of the AVCS and turbo banjo bolt screen clogging issues on the later MY 2.5 turbos (and subsequent turbo failures).

You MIGHT be ok on a Wal-Mart 10W-30, but there's no need to experiment giving your application, IMO. Unless, of course, Ramblejam provides you with some kind of warranty.
48.gif
Ed Hackett on here does have some good uoa's on RT5 in a stock, non-tracked '08-ish? Legacy GT but HDEO's are different.

Nice drop in silicon!
thumbsup2.gif


-Dennis
 
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