balbrec2

From what I know, all the main clearances in the 3.6 and the 2.5 are the same. 0w20 is engineered to maximize HP and efficiency, not necessarily protection. So, if that's the case, why would it be a problem running 5w30?

From what I know, the design engineers at Subaru are a lot smarter

than you or I. Stick with what they recommend.

It would be better if the poll included a "none" category.

I change my oil at 6k and have never seen the dipstick below full. The oil is also very clean. I suspect that not needing to add oil is the norm.

I've never like to see oil come out of an engine looking new. It means its

not working to keep deposits out of the engine. Even normal combustion by

products should cause the oil to darken somewhat.

I have a 2015 Legacy 2.5 with 29k mi. and a 2015 Impreza 2.0. with 20k mi.

Neither uses any measurable amount of oil between 6k oil changes.

These cars are not babied yet not beat on either. Both broken in according to the owners manual recommendations. Guess we just got lucky!

Next? I don't think that far ahead with my cars. Haven't had the Legacy a year yet and

since I tend to keep my cars a very long time, my next car isn't even on the long range radar. Very happy with this one in all regards.

Is there some documented evidence that this needs to be

done in lieu of the service intervals in the maintenance manual?

I just can't see spending the time or money on something that is

not needed. To me this is like changing oil at 3K miles instead of the

recommended 6K. Unless you have a proven need, why ??

Subaru says for the 2.5, 0W-20 synthetic every 6000 miles with a new filter.

Use what ever flavor you like, keep all receipts. Or take to your Subaru dealer

for maintenance. Stretching past this may be ok according to the oil manufacturer

but since Subaru is who holds the warranty to your engine, the wise thing to do

is follow their recommendations. After the warranty is expired , do as you see fit!

13k running Amsoil - haven't added any. Check monthly.

No way would I go that long on any oil! It may retain some

of it's lubrication properties but oil gets dirty with use and TBN declines also. After a while it may lubricate but it can't do the rest of it's job. Have you ever sent a sample to the lab for UOA? I'd be curious.

has anyone looked into whether changing out the RSB would cause any issues

with the new vehicle warranty?