Lubricant Related Questions For 2015 Subaru WRX

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Just picked up a 2015 WRX and I have a couple lubricant related questions.

I'm sure this question has been answered before, but what are you guys thoughts on a good oil for this car. I have been leaning towards one of the Amsoil 5W-30s since I have good luck with Amsoil in my other rigs and I am a dealer, but I am open to other reccomendations as well.

Amsoil recommends the 5W-30 Signature series, but I am concerned about the 3.2 HTHS and it being on the lighter end of the 30s.

The next option is the 5W-30 European Car Formula. The HTHS of 3.6 and the KV of 12.2 make this look to be an excellent choice, but the TBN of 5.8 doesnt seem to be too desirable although it does seem to hold up well in my TDi under 10k OCIs.

The next oil which looks to be a decent performer is the Amsoil 5W-30 Heavy Duty Diesel. HTHS of 3.5 KV of 11.7 looks decent although a bit higher Noack Volatility than the other two.

And of course there is always the factory Subaru 5W-30 which I dont know anything at all about.

Let me know what you guys think of these oils and also if you have any other recommendations.

Thanks
 
Congrats, nice ride. CVT or manual?

I think regular 5w30 SS is a great choice. I'd probably step up a grade or move to the HDD 5w30 down the line as the car ages.

Just curious, what does the manual recommend? Subaru was always a believer of matching viscosity to ambient temperatures. My 03 Forester can use anything from a 5w30 to a 20w50.
 
Someone can correct me if I'm wrong, but with the turbo 2.0L engine being a new entity for the WRX, I'm not sure it is yet *known* if there is an oil better then the recommended (see earlier WRX/STi engines that don't do well on the spec'd 5w-30).
 
I believe your owner's manual requires API SM/SN. If that concerns you, use Pennzoil Platinum 5w-30 or one of Amsoil's API rated oils. If it doesn't concern you, their Euro Full SAPS 5w-40 is what I'd use in the Amsoil lineup.
 
Amsoil Series 3000 HDD in the summer and Signature Series in the harsh winters - both in 5W-30.
 
its a turbo direct injection motor making 134hp/Liter. I'd run m1 0w40, RTS 5w40 or a thick 5w30 euro spec oil.

If you do significant short tripping and drive like there is eggshells under the gas pedal any 0w30/5w30 should be ok.

you may just want to stick with the oem 5w30 and oil filter.. its only the second year for this engine.
 
Guy right next door to me has a WRX it's maybe three years old and has plenty of mods and he runs RTS 5-40 and has no issues and he drives it every day like he stole it!
 
The Euro formula might be the best choice, in light of the recommended OCI; isn't it at 3750 miles now? At that distance the lowerTBN won't be an issue.
 
Having run Amsoil SSO 0W-30 for 7,500 mile intervals (my uoa's are in the uoa forum) and seeing gathermewool's STI uoa's on SS 5W-30, I would go with something more robust.

SS is not API/ILSAC certified, so you may as well run Amsoil HDD 5W-30 if you go that route IMO.

Check the STI thread that was recently posted for some good recommendations. Yes, the engine is new but the early uoa results are showing that it is the same on as all other Subaru turbos. There has also been some very high fuel dilution in some instances as well, especially during the winter. More of those were on the Forester DIT, but I recently saw a '15 WRX uoa from last winter with fuel dilution as well.

-Dennis
 
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The issue not mentioned yet is intake valve deposits. The Subaru FA20 DIT is a bit too new to know if deposits are a problem yet, but they have been in other direct-injected engines.

In that light, I think the Low-SAPS 5w30 Euro car formula is an excellent option. I've been using M1 ESP 5w30 in my WRX and it seems to work very well in the older EJ engine. The VW/Audi community seem to like it in their DI engines as well.

If you want to stick with ILSAC 5w30, why not just use XL, or even OE? They've got pretty good HTHS viscosity and either should last the OEM change interval of 6k miles.
 
Originally Posted By: gpshumway

In that light, I think the Low-SAPS 5w30 Euro car formula is an excellent option. I've been using M1 ESP 5w30 in my WRX and it seems to work very well in the older EJ engine. The VW/Audi community seem to like it in their DI engines as well.


I used M1 5W-30 from 5,000-115,000 miles and M1 5W-30 ESP from 115,000 to 146,000 miles in my 2007 Mazdaspeed 3. No deposit issues to date.
 
Originally Posted By: buster
Congrats, nice ride. CVT or manual?

I think regular 5w30 SS is a great choice. I'd probably step up a grade or move to the HDD 5w30 down the line as the car ages.

Just curious, what does the manual recommend? Subaru was always a believer of matching viscosity to ambient temperatures. My 03 Forester can use anything from a 5w30 to a 20w50.


Thanks man, its a CVT.

Subaru reccomends 5W-30, but basically says you can use 5W-40 temporarily.
 
Originally Posted By: Rand
its a turbo direct injection motor making 134hp/Liter. I'd run m1 0w40, RTS 5w40 or a thick 5w30 euro spec oil.

If you do significant short tripping and drive like there is eggshells under the gas pedal any 0w30/5w30 should be ok.

you may just want to stick with the oem 5w30 and oil filter.. its only the second year for this engine.


Im definitly considering the T6 5W-40 as it doesnt seem to be too heavy of a 40 from what I've seen and looks to hold up well in the older WRX engines. Another oil I saw that I am somewhat confused by is the Castrol EDGE 0W-30 Euro thats made in Belgium. Is this the same thing as GC?

The 5W-30 Subaru oil may be a good choice too, I just cant find any specs, VOAs or UOAs on it. Does anyone know anything about it?
 
Originally Posted By: Bandito440
I believe your owner's manual requires API SM/SN. If that concerns you, use Pennzoil Platinum 5w-30 or one of Amsoil's API rated oils. If it doesn't concern you, their Euro Full SAPS 5w-40 is what I'd use in the Amsoil lineup.


I am somewhat concerned about this because of it being under warranty. How will the dealership look at this if I have engine failure and I have not been using an API rated oil?
 
Originally Posted By: gpshumway
The issue not mentioned yet is intake valve deposits. The Subaru FA20 DIT is a bit too new to know if deposits are a problem yet, but they have been in other direct-injected engines.

In that light, I think the Low-SAPS 5w30 Euro car formula is an excellent option. I've been using M1 ESP 5w30 in my WRX and it seems to work very well in the older EJ engine. The VW/Audi community seem to like it in their DI engines as well.

If you want to stick with ILSAC 5w30, why not just use XL, or even OE? They've got pretty good HTHS viscosity and either should last the OEM change interval of 6k miles.


I keep leaning towards the AMSOIL Euro 5W-30, although I just noticed that the NOACK is 10% and there is no 4 ball where test, but the other Euro Spec oils are showing a .45mm wear scar vs .35 on Amsoil's other 5W-30s. How relevant is the NOACK and wear scar?
 
"GC" used to be made in Germany, thus "German Castrol" or GC for short. It's a heavy duty 30wt with HTHS >3.5 and works well in the older Subaru EJ engine. Great for winter, but not as good for heavy use in the summer as RT6.

5w30 Subaru oil is just Idemitsu 5w30 with a Subaru label on it, it's no better or worse than any other ILSAC 5w30 like Pennzoil Platinum or Mobil 1.
 
Originally Posted By: srl1104
How relevant is the NOACK and wear scar?


10% Noack is fine.

"wear scar" is just marketing hype, ignore it.
 
Originally Posted By: gpshumway
The issue not mentioned yet is intake valve deposits. The Subaru FA20 DIT is a bit too new to know if deposits are a problem yet, but they have been in other direct-injected engines.

In that light, I think the Low-SAPS 5w30 Euro car formula is an excellent option. I've been using M1 ESP 5w30 in my WRX and it seems to work very well in the older EJ engine. The VW/Audi community seem to like it in their DI engines as well.

If you want to stick with ILSAC 5w30, why not just use XL, or even OE? They've got pretty good HTHS viscosity and either should last the OEM change interval of 6k miles.


It's not as new as you might think. It's been in the Japanese market since 2012 and was in the Forester since 2014 I believe. I'm a bit curious about the intake valve deposits too.

-JL
 
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