2018 Subaru WRX - Oil

[Patman]

Originally Posted by benjy
real synthetic PAO + Ester oils are the best. Ester oils handle heat better than other types. Redline my fav recommends 2,000 break in on conventional oil to better seat the rings, a good idea for subies for sure. most of today's "synthetic" oils are all or mostly group III highly refined CRUDE oils,


That is just flat out false. There are actually very few synthetics out there which use 100% group 3 as their base stock. The major synthetics are all blending in some GTL or PAO to some degree.

 

[MRC01]

Originally Posted by slybunda
Head gaskets are known to die often on subarus regardless of how well its looked after. So id just put the cheapest oil in.

That was a prior generation of engines. I should know, it affected my 2004 Forester. Subaru fixed that problem several years ago; it should not affect the OP's 2018.
However, you make a good point about cheap oil. The cheapest oil that meets the specifications can be the best way to go. It's hard to find UOAs or other evidence showing otherwise.

 

[Patman]

Originally Posted by MRC01

That was a prior generation of engines. I should know, it affected my 2004 Forester. Subaru fixed that problem several years ago; it should not affect the OP's 2018.
However, you make a good point about cheap oil. The cheapest oil that meets the specifications can be the best way to go. It's hard to find UOAs or other evidence showing otherwise.


I disagree, do you really think Supertech conventional will protect that hard driven turbo engine as well as a good synthetic? What happens when oil temps hit 300F?

 

[normal_guy1]

I own a 2016 wrx, same engine as yours (FA20 DIT) and live in New England (so it gets cold here in the winter). My first two oil changes (6k and 12k miles) were free from the dealership, so it was the Subaru 5w-30. From then on, I've used Pennzoil Platinum exclusively (but I have no doubt other oils would perform similarly). Recently switched to Pennzoil Ultra Platinum because it was almost the same price ($24.97 on Walmart/Amazon Prime) as non-ultra. Here is my used oil analysis over a year.

What you'll probably notice: Higher fuel dilution in the colder/winter months, and thus lower viscosity. Wear metals a bit higher, but nothing crazy.

Driving Habits:
- About 80% highway, 20% city
- Shifts at 3.5k-4k RPMs
- Engine breaking, downshifting, and rev-matching when appropriate
- 5th/4th Gear downshift when passing
- Boost after oil temp reaches 145 deg F (as shown by in-car Tri-Gauge Cluster)

Maintenance Habits:
- Oil Change around 5k miles
- Air Filter (Cabin and Engine) by owner's manual recommendations (12k miles, 24k miles)
- Tire Rotations every Oil Change
- Recently performed 30k service by owner's manual (brake fluid, clutch fluid, etc).

I do all maintenance myself, this car is super easy to work on. Maintenance items are easily accessible (so far).

No plans for modifications (including ECU flashing/Accesport OTS Tuning) until car is out of powertrain warranty. To be honest, the stock FA20 wrx is just a turbo'd econobox. Now if you're modding it, that could be a different story.

EDIT:
sample 1 and 2: Pennzoil Platinum 5w-30 dexos1
sample 3 and 4: Pennzoil Platinum 5w-30 dexos1g2 (formula change)
sample 5: Pennzoil Ultra Platinum 5w-30

 

[SilverFusion2010]

M1 5w-30

 

[dlundblad]

Originally Posted by Patman
Originally Posted by MRC01

That was a prior generation of engines. I should know, it affected my 2004 Forester. Subaru fixed that problem several years ago; it should not affect the OP's 2018.
However, you make a good point about cheap oil. The cheapest oil that meets the specifications can be the best way to go. It's hard to find UOAs or other evidence showing otherwise.


I disagree, do you really think Supertech conventional will protect that hard driven turbo engine as well as a good synthetic? What happens when oil temps hit 300F?


"Cheap" as in plain Jane conventional is a bad idea regardless of brand in a turbo engine IMO.

I had people here recommending PYB 10w30 (back when it was the hard stuff) in the Volvo in my signature. No thanks.. A3/B4 for me.

*** I hardly see anyone now recommending PYB these days. Used to be a BITOG favorite.

 

[SilverFusion2010]

I still like PYB for a short cleaning oci. It's good oil, but you can usually get a jug of full syn for less with rebate

 

[MRC01]

Originally Posted by dlundblad
Originally Posted by Patman
Originally Posted by MRC01

That was a prior generation of engines. I should know, it affected my 2004 Forester. Subaru fixed that problem several years ago; it should not affect the OP's 2018.
However, you make a good point about cheap oil. The cheapest oil that meets the specifications can be the best way to go. It's hard to find UOAs or other evidence showing otherwise.


I disagree, do you really think Supertech conventional will protect that hard driven turbo engine as well as a good synthetic? What happens when oil temps hit 300F?


"Cheap" as in plain Jane conventional is a bad idea regardless of brand in a turbo engine IMO.
...

I've heard that conventional wisdom many times. But I've never seen UOA or other hard evidence that supports it. Conventional oil may shear down faster, and synth oil does flow better when cold. But it's hard to quantify these advantages pragmatically: for example with UOAs or wear numbers. Conventional oil may have a shorter service interval, but it should protect just as well during that interval.

Anecdotally, years ago I owned a '95 RX-7 which is a twin turbo wankel. Making > 250 HP from 80 cubic inches, driving at max performance at SCCA events, it got hotter than most piston engines. I always ran conventional oil because that's what Mazda specified for this car. That wankel had oil injection at high power high RPM and Mazda believed synthetic oil might not burn properly due to its higher flash point. The point is, conventional oil can work fine in at least some high performance turbo engines.

 

[MRC01]

Interesting UOAs. Do you have mileage intervals driven on each oil so we can amortize the wear metal rate per mile?
OK - I just saw it. Other than the blip with Cu, these numbers look like normal random variations I've seen across a variety of engines. All these oils were doing their job. No strong trends.

 

[David2468]

Hi all

Just wanted to say thank you for all the advice and anecdotes and wisdom. Much appreciated. It was a great read in the thread....Not sure if I should broach the subject of oil filter recommendations.

Haha...
Thanks again.

 

[jimmyturner]

Sorry to bump this thread guys but i just bought a 2020 wrx and i'm about to do my oil. I been reading the past few hours and i'm more confused than before lol.

So far i been looking at castrol magnatec 5w30 , valvoline advance 5w30, motul ecolite 5w30 or motul xclean 5w30. I'm on the wrx forums and they said the fa20 engines destroy oil so fast so i need something good. Btw i try to change my oil about twice a year but sometimes i do go longer, like every 8 months etc. I don't drive a lot but most of my commute is stop and go.

Please help. Thanks!

 

[kschachn]

If a topic interests you then you should make a new one rather than resurrecting an old one. Then you don't have to apologize to us guys either.

 

[PimTac]

Originally Posted by jimmyturner
Sorry to bump this thread guys but i just bought a 2020 wrx and i'm about to do my oil. I been reading the past few hours and i'm more confused than before lol.

So far i been looking at castrol magnatec 5w30 , valvoline advance 5w30, motul ecolite 5w30 or motul xclean 5w30. I'm on the wrx forums and they said the fa20 engines destroy oil so fast so i need something good. Btw i try to change my oil about twice a year but sometimes i do go longer, like every 8 months etc. I don't drive a lot but most of my commute is stop and go.

Please help. Thanks!




Use whatever is in your stash.

 

[jimmyturner]

Originally Posted by PimTac
Originally Posted by jimmyturner
Sorry to bump this thread guys but i just bought a 2020 wrx and i'm about to do my oil. I been reading the past few hours and i'm more confused than before lol.

So far i been looking at castrol magnatec 5w30 , valvoline advance 5w30, motul ecolite 5w30 or motul xclean 5w30. I'm on the wrx forums and they said the fa20 engines destroy oil so fast so i need something good. Btw i try to change my oil about twice a year but sometimes i do go longer, like every 8 months etc. I don't drive a lot but most of my commute is stop and go.

Please help. Thanks!




Use whatever is in your stash.


motul x-clean it is then lol. i have 3 5qt jugs of it. Only reason why i posted in this thread because it's dexos 2 and people say for TDGI engines dexos 1 gen 2 is probably better. I'll just use this. Thanks

 

[Ignatius]

I would used a Valvoline Synthetic 5w30, Valvoline Advanced Synthetic works well for preventing carbon deposits and Valvoline Modern Engine works well for cleaning carbon deposits. Both are stout enough to handle what the 2.0L Subaru DIT throwns at it.

 

[bluesubie]

Originally Posted by Ignatius
Both are stout enough to handle what the 2.0L Subaru DIT throwns at it.

Except for HTHS and kinematic viscosity. I'd pick a C3 or similar oil in a WRX over a GF5/6 oil.

 

[jimmyturner]

Originally Posted by bluesubie
Originally Posted by Ignatius
Both are stout enough to handle what the 2.0L Subaru DIT throwns at it.

Except for HTHS and kinematic viscosity. I'd pick a C3 or similar oil in a WRX over a GF5/6 oil.


The motul dexos 2 i have is C2/C3. But then the whole lspi thing is confusing to me, that's why i asked which one i should go with, the whole dexos 1 gen 2 or dexos 2 in the motul i have. Those hours of searching threads got me more confused.

So i'll just run this and then search for a better oil on the next oci?

 

[Gokhan]

Since they recommend an API SN/SN PLUS/ILSAC GF-5 synthetic 5W-30 for the Subaru WRX or Subaru WRX STI, I would go with a top-quality GM dexos1 Gen 2/Gen 3 5W-30. Either the Mobil 1 Extended Performance 5W-30 or the Mobil 1 Extended Performance High Mileage 5W-30 with its higher PAO content (about a third of the base oil), Group V alkylated naphthalene (AN) content typical of American Mobil 1 oils, and extra antioxidant for extended oil-change intervals is an excellent choice for reducing the intake-valve deposits (IVD) and turbocharger deposits.

The ACEA C2/C3 dexos2 oil with HTHS = 3.5 cP you have is OK to use. It doesn't provide LSPI protection, but I doubt your TGDI engine has a high-enough BMEP to experience significant LSPI events. Subaru didn't bother to require SN PLUS either. Typical ILSAC 5W-30 has HTHS = 3.0 - 3.1 cP, although some have a little higher HTHS.

I wouldn't worry much about some people on oil forums recommending thicker oils. OEMs know what viscosity to recommend better than them. You don't need a higher viscosity unless you're racing etc.

 

[Virtus_Probi]

Originally Posted by Gokhan
Since they recommend an API SN/SN PLUS/ILSAC GF-5 synthetic 5W-30 for the Subaru WRX or Subaru WRX STI, I would go with a top-quality GM dexos1 Gen 2/Gen 3 5W-30. Either the Mobil 1 Extended Performance 5W-30 or the Mobil 1 Extended Performance High Mileage 5W-30 with its higher PAO content (about a third of the base oil), Group V alkylated naphthalene (AN) content typical of American Mobil 1 oils, and extra antioxidant for extended oil-change intervals is an excellent choice for reducing the intake-valve deposits (IVD) and turbocharger deposits.
The ACEA C2/C3 dexos2 oil with HTHS = 3.5 cP you have is OK to use. It doesn't provide LSPI protection, but I doubt your TGDI engine has a high-enough BMEP to experience significant LSPI events. Subaru didn't bother to require SN PLUS either. Typical ILSAC 5W-30 has HTHS = 3.0 - 3.1 cP, although some have a little higher HTHS.
I wouldn't worry much about some people on oil forums recommending thicker oils. OEMs know what viscosity to recommend better than them. You don't need a higher viscosity unless you're racing etc.

It is worth noting that Subaru recalled early WRXs and FXTs with the FA20DIT engine due to LSPI concerns. Some folks got new engines and a lot of damaged plugs were found, supposedly some engine management changes were made through new ECU programming but good luck finding out exactly what they were.
I was feeling pretty good about having started using low calcium/near zero sodium M1 5W30 well before the recall and still want the oils I use in my FXT to have gone through some kind of LSPI testing (dexos1 Gen 1, SN+, Ford -B1). Valvoline AFS 5W30 is d1G2/SN+ as well as high HTHS for a GF5 type oil at 3.2 mPas.

 

[avi1777]

first thing is to drop the cats,get a bigger y pipe,proper tune,cai,a good exhaust, lighter pulleys and flywheel and last but definitely not least tein coilovers,then use what ever syn that meet the specs.i would run the 300v as I mentioned before.