0w20 oil to reduce engine noise in a Subaru OB?

Not open for further replies.
Dec 4, 2004
Lexington, KY
I am looking for a 0W20 synthetic oil for my 2017 Subaru Outback 2.5.that will help reduce engine noise while the engine is cold or warm.
Well, first things first, you won't find a concrete answer. There are a few oils that are held in high regards when it comes to volume, but very little evidence to support them actually being quieter than other brands. That said, here are a few of those "quieter" oils (in my opinion): QS Ultimate Durability (API SN) PPPP/PUPPP (API SN) Castrol Edge (API SN) Amsoil Redline etc. The common thread with those oils is a higher moly/boron composition than "average". If I were in your shoes, I'd try any of those that have your required approvals/certifications until you found one that you like.
I had the same engine in my Forester. You won’t find a -20 that will make a difference. Your choices are using something heavier and risking warranty problems, or ignoring a bit of noise. Mobil 1 0w-40 or Rotella T6 5w-40 will quiet things down, but they’re heavier than you’re looking for.
What is the noise? What do you expect an engine oil to do to reduce this noise? Your efforts might be better spent somewhere else.
Originally Posted By: Warstud
Try Castrol Magnatec
I knew I was forgetting one. This is another common "quiet" oil.
Originally Posted By: Russell
I am looking for a 0W20 synthetic oil for my 2017 Subaru Outback 2.5.that will help reduce engine noise while the engine is cold or warm.
Check in the owner's manual and if it shows I'd go for a 5W20 or 0W30 or 5W30. In my MB which called for 0W40 I used 5W40 as the former was a bit too noisy for my liking upon start-up, this solved the problem.
What have you tried in it so far that has been 'noisy'? In my Accord that also specs 0w20, I've used Mobil 1 EP, then Pennzoil Platinum, then Mobil 1 AFE, and the AFE is what I've kept using since it has made the valvetrain seem noticeably quieter on cold starts. Not a huge difference but there is one. As was suggested above, Castrol Magnatec is next.
PUP was the loudest in my Cruze and tied for last in my 3.5L ecoboost … Iused a digital dB meter …
Originally Posted By: parshisa
so basically all the oils are quieter but Mobil 1? lol
I switch back and forth between oils I've used Mobil 1 in my Toyota Corolla and you certainly couldn't prove it my me.
I know the 3400 in my sister's 05 impala was a tad on the noisy side all summer, (she bought it at the beginning of summer, and it had just been serviced at the local garage they normally use, not sure what oil he uses, but always uses carquest red filters, and before that it was always the local Chevy dealer) I did an oil change on it a week ago, with the specified 4 qts of Dexos1 5w30 (AutoQuest - Meijer/Warren) ,and an XG3387. She came down for a visit yesterday, and it was much quieter. almost unnoticeable. forgot to check the oil level before starting the OC to see how low it was...
I just put M1 AFE in our newer Forester, which has the same engine. Seems reasonably quiet. A little noise on engine start is part of what makes a Subaru a Subaru. The '17 sounds almost exactly like the '09, which is a little scary since these have entirely different engines that just happen to share the same nominal displacement.
We added Molyvan-L which quieted a different (GM) engine. Every time we have changed the oil on our Subaru 2.5 (with PU, M1EP, Subaru oil) it quieted the engine. They just don't make much noise to begin with except the roaring under heavy acceleration with the older CVT.
Last edited:
Valvoline oils are usually loaded with boron (iirc) so maybe give 0w20 SynPower a try. My old Impreza was noticeably quieter using Valvoline products.
I switched my father's Subaru to Mobil 1 0W30, it is running quieter than the 0W20 the dealership was supposedly using in it.
Not open for further replies.