2021 Subaru Outback 2.5L / Amsoil OE 0w-20 2.8k miles

[Nuclear_42]

Here's my 2.8k sample on my 2.5NA 21 Subaru Outback. I used a regular Wix filter. Viscosity is on the lower side of the range. I'm happy with the results and will change the current oil around 3-3.5k miles. I spoke over the phone with the lab about the fuel dilution. Subaru recommends 6k mile/ 3k mile severe svc intervals. The tech noted 5-6k mile runs are ok. Due to 5% being very common on newer DI cars. This Subaru sees 4 mile round trip daily work commutes and highway 1-2x a week 80% city/ 20% hwy 6-7k mile annually. I think 3-3.5k spring/ fall oil changes should be fine with Amsoil OE.

Here's my previous run results with Amsoil Signture 0w-20 for reference:

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

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...

bobistheoilguy.com

 

[fantastic]

Other than fuel it doesn't appear too bad. 5% is max I would want to see in a gasoline engine. You'll find out what your sub does and adjust mileage from there. It's a shame though that these excessive fueled engines can ruin a longer run on expensive oil. Thanks for sharing.

 

[bluesubie]

Hey I was right when I said there wouldn’t be much difference in fuel dilution with a shorter OCI.

 

[Oliveoil2]

Looks like you have an injector leaking at 300k. This is a good use of a UOA!

 

[SubieRubyRoo]

It's a shame though that these excessive fueled engines can ruin a longer run on expensive oil.

It’s not so much “excessively fueled” as it is “really high pressure fuel, atomized very finely, and introduced just before ignition starts the party”…

Because the fuel is injected in the combustion chamber and not sucked into it when already mixed with air, there is more piston top/chamber wetting, and liquid fuel doesn’t burn. Then this fuel gets on the cylinder walls and makes it past the rings. Voila, higher fuel dilution and better mileage.

 

[fantastic]

It’s not so much “excessively fueled” as it is “really high pressure fuel, atomized very finely, and introduced just before ignition starts the party”…

Because the fuel is injected in the combustion chamber and not sucked into it when already mixed with air, there is more piston top/chamber wetting, and liquid fuel doesn’t burn. Then this fuel gets on the cylinder walls and makes it past the rings. Voila, higher fuel dilution and better mileage.

Very good information.

 

[Artem]

Looks like you have an injector leaking at 300k. This is a good use of a UOA!

Huh? at first I was confused and wanted to ask what you’ve been smoking but then I went and looked closer at the report.