2021 Subaru Outback 2.5L / Amsoil Signature 0w-20 4.9k miles

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Here’s my results for the Subaru Outback Limited 2.5L Direct Injection NA engine. It had roughly 4800-4900 miles at sampling. Amsoil Signature 0w-20/ Wix filter. Oil was changed last September and sampled this March. This vehicle is used for roughly 4 miles daily commute round trip in Minnesota. I’m quite surprised at the fuel dilution percentage. During the very cold winter days remote start is used and we try to limit it to 5 minutes or less. I’ll be changing the oil soon and resampling in 3k miles. I’m thinking it has to do with the overall boxer engine design. Nonetheless the oil viscosity held up great.
 

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Those are good results considering the severe service it was put through. Viscosity is solid despite the fuel dilution.
 
Short trips and DI don't pair well together. Take it out for a long trip every once in awhile
 
Does the Outback have the digital readout for the engine oil temp like on my Forester? What does it get up to on your commute on a typical Minnesota morning?
 
Does the Outback have the digital readout for the engine oil temp like on my Forester? What does it get up to on your commute on a typical Minnesota morning?
Typically 140-180 F* depending on how frigid the weather is.
 
If you are going to keep those driving habits, substitute 1 or 2 qts of 5W30 AMSOIL Signature with the 0W20.

The fuel dilution on DI engine is NOT a good thing. Subaru have narrow bearings, they need more MOFT than a diluted 20 grade will ever provide.

Owned nine Subaru over the years. I have a couple relatively new "clankers in the driveway due to the D.I. "curse" - Ken
 
Wear metals are normal, viscosity is fine... I would try and take it on a longer trip every once in a while but other than that I wouldn't worry about it at all.
 
Wear metals are normal, viscosity is fine... I would try and take it on a longer trip every once in a while but other than that I wouldn't worry about it at all.
My Iron was 6 and Aluminum 2 with twice the "Lube time" miles.

In a P.I. Subaru FB motor.

I don't use a UOA to look for impending engine damage.

Got to listen to the engine - if it's clattering or knocking - It's in trouble.

You have to excise and wash down the filter media debris and weigh it.
The other half of shed particulate is likely on the pan floor and front cover shelves.

oil report crop.jpg
 
The remote start doesn't help either but bravo for keeping it at 5 minutes or less in your climate. I see so many people complain about the 10 minute max using the app. Actually that might be twice consecutively for 10 minutes?

Good uoa given the conditions though. Probably wouldn't be much difference in fuel dilution in winter with the 3k OCI IMO.
 
These engines do not seem to produce oil temps over 190 unless pushed on the highway.
My Legacy gets higher temps quicker than my Impreza but not by much. I was driving about 30 miles when I noticed that temps didn't really get over 180. This was when it was colder a few years ago. I asked one of the tech reps and they told me 180 is normal operating temp.

I'm guessing that because the Legacy has the 2.5l as opposed to the 2.0, that is the reason it gets higher quicker. I'm gonna have to pay more attention when it is really hot in the summer to see what "normal" temp is for both.
 
Amsoil oil is overkill in my mind for your usage. NAPA synthetic 0W20 is all that is needed.

Unsure of the need for a UOA unless your going to push the OCI.

Fuel dilution is not great in a gas engine.
 
It would be interesting to see if a plug in block heater would help with the dilution (assuming you do not have one) as well as eliminating the need to warm the engine.
 
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