Thought some people here might be interested in this. This is from my 05 9-2x Aero (2.0L Turbo). I do 99% highway driving, and drive about 60 miles a day. No oil added and I used the OEM filter.

http://www.thebarricks.com/images/UOA/UOA-32025.PNG

Better than I expected, especially after reading the many threads where people have problems with the M1 5W30. I'm trying GC 0W30 right now, but so far the only difference I'm noticing is a loss of 2-3 MPG.

Good looking UOA.
2-3 MPG with GC? Wow, that's on the high end, but not unheard of.

Good looking UOA.
2-3 MPG with GC? Wow, that's on the high end, but not unheard of.

Yeah, I was getting a consistent 27-28, now I'm in the 25-26 range. Since I drive all highway (seriously, about 2 blocks total in town each day), the thicker GC is probably hurting the mileage a bit until it warms up. And with the weather dropping in to the teens lately, it can't be helping it warm up any faster.

Oh well, it will be interesting to see the comparison between the two when I do the GC UOA in a couple months. Hopefully the difference in outdoor temps doesn't effect the final results that much.

The fuel dilution is spot on what you'll see with a lot WRX's. This is one of the longest OCI's that I've seen on a M1 30 weight in a WRX (or Saabaru. :) ). That's great that it stayed in grade for 7,700 miles. I think the viscosity of this is similar to the regular M1 so it must be the additives. :cool: The highway driving definitely helps the viscosity stay up there though.

What kind of air filter are you running?

The funny thing is that you'll get a few hundred views on this, but you'll get a few thousand views if you ask how often should you change your oil . :)

-Dennis

yeah, i'm surprised that the oil didn't thin out more, I think it's as thick as regular M1 5W30.
plenty of additives left, even moly

What kind of air filter are you running?
To tell you the truth, I can't remember for sure what I replaced the stock one with. I think it's a Napa gold filter, but there's a small chance it's a (gasp!) Fram filter.

Your silicon might drop with an OEM air filter. Although I've never managaged to get into the single digits like some Subaru owners have running OEM.

I'm still amazed at this viscosity. Are you sure you didn't add a quart of fresh oil the day before you took a sample? :D Don't be surprised if the GC thickens up to a 40 weight if you run the same OCI.

-Dennis

You should post this on bobistheoilguy. There are several WRX and Aero UOA's over there.

http://theoildrop.server101.com/forums/postlist.php?Cat=0&Board=UBB3

-Dennis