New-to-me Subaru, what oil to go with?

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Sorry bud.

You're completely correct. I read your post and didn't read the parentheses. (One on each head) .

My post reply was on 5-30. That's what I run on my soch n/a Subaru. Didn't mean I ran original head gaskets that long. Any man that did that needs to buy a lottery ticket.

On the "gaskets done at the dealer" is my biggest concern. If you only knew the process. I seen guys take heads off, whiz wheel both block and heads, torque to **** near 90 lf/lbs.

Once again, you are correct. I read your reply too quick. My apologies.
So about a year ago, the Subaru dealership from the previous owner did the HG, radiator, and thermostat. During the buying process I had the dealership call the original dealership send the maintenance record, and they found the HG during a state inspection. The owner had them do the HG right then and there, the car never broke down and was never brought in for oil/coolant loss or coolant in oil or vise versa. The dealership I bought it from also did a compression test for me and all the cylinders are within 3psi of each other averaging 144psi
 
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"Old Lady" really? After 50 years I still call my wife Princess and it works.
Don't know much about Subaru but with what I've read on their history and her driving I would look at any 0/5w-40.
I cannot rely on the wife telling me anything about how her car is running especially when/if it needs an oil change. That's my job!
I'm pretty good about keeping track of all my services. Only thing that wife tells me is when it's obvious there's something going on like some sort of new noise. Or if the Honda maintenance miter flashes in her face 15%
 
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The non-turbo EJs will happily run any xW-30 from now until the end of time. I will probably even run a thicker 20 weight in my car this winter, just for the hockey sticks of it. The EJ257s most times like thicker oils due to the overheating condition of the driver rear cylinder. I experimented over the years with xW40s in my non-turbo EJs and all I ever really noticed was the car went ~25 miles fewer to a tank compared to the 30s. Sure, the UOAs tended to be just ever so slightly "better" but I'm not going to ever see an EJ fail because of a spec oil. I've had 5 EJ25s, with every single one making it between 160k (still in use)-234k(sold & still running) with no known rebuilds and loving the cheap SN 30 weights. Agree on your other maintenance tips, the PS trick lets you slowly change the total volume with minimal work. The "lifetime" filter that came on older cars with 4EATs was another phenomenally easy task to change!
I got really bummed when I stuck my head under my '09 Forester XT w/ 4EAT to not find the spin on trans filter where it should be.
 
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The non-turbo EJs will happily run any xW-30 from now until the end of time. I will probably even run a thicker 20 weight in my car this winter, just for the hockey sticks of it. The EJ257s most times like thicker oils due to the overheating condition of the driver rear cylinder. I experimented over the years with xW40s in my non-turbo EJs and all I ever really noticed was the car went ~25 miles fewer to a tank compared to the 30s. Sure, the UOAs tended to be just ever so slightly "better" but I'm not going to ever see an EJ fail because of a spec oil. I've had 5 EJ25s, with every single one making it between 160k (still in use)-234k(sold & still running) with no known rebuilds and loving the cheap SN 30 weights. Agree on your other maintenance tips, the PS trick lets you slowly change the total volume with minimal work. The "lifetime" filter that came on older cars with 4EATs was another phenomenally easy task to change!
Do yours "tick" borderline knocky-knocky for a short time upon first startup or is that not a Subaru EJ251 thing? Maybe some minutes, the colder the longer before it goes away? I've always been curious about this.
 
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No, mine don’t “knock” on startup. They are fairly noisy in the valvetrain til things heat up and the lash comes into range. I’m actually thinking of trying a thick 20wt for “winter” and run a vacuum sample UOA in maybe Jan-Feb (probably 2500-3500 miles). The other downside to the EJ design is when it’s REALLY cold, fuel does not like making that 90* turn from the vertical port into the chamber and it can seriously stumble if you have to punch it when the needle’s still on C. Oh well…
 
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Might be. But Subarus are not known for piston issues, believe it or not! 😂 Some FBs had bad oil rings, some EJs had HG issues, but pistons & 4EAT issues are generally quite rare.

Toss a 0/5w40 in it (Rotella T6 is always a safe bet) and motor on! 😎
That helps piston slap? Still tying to figure out if it is even that
Thought EJ251s did that (I hate it)
*could be noisy valvetrain like you say.

Maybe try @High Performance Lubricants and their 0W-20? HTHS 2.8 maybe 2.9 right at the cut-off mark? The eternal debate is.. can you then use that all year!
 
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Maybe try @High Performance Lubricants and their 0W-20? HTHS 2.8 maybe 2.9 right at the cut-off mark? The eternal debate is.. can you then use that all year!
I need to do some research & find out what HTHS was pretty standard for 5W30s of 2007 SM oils… if the 2.9 is in the range, that may be acceptable. I had my eye on that already once @OVERKILL had the data posted for his “personal” blend!
 
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Rip the valve covers off and check cold lash on both intake and exhaust. Real easy to adjust.
Easier than taking the valve covers off an H4? 🤣🤣

I'll be buying that case of that OVERKILL 0W-20 in October, it just isn't possible to buy it this month I don't think but I'm getting there. I wanted to buy it last month but I couldn't do that either.
 
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Might be. But Subarus are not known for piston issues, believe it or not! 😂 Some FBs had bad oil rings, some EJs had HG issues, but pistons & 4EAT issues are generally quite rare.

Toss a 0/5w40 in it (Rotella T6 is always a safe bet) and motor on! 😎

Ive been running T6 in my Impreza with no issues since I got it from japan(2013).

The valve train is indeed loud at cold startup, but quiets down when it gets warm.

Sample from 2016 @ 4500kms/6 months interval. Ej20k
Screenshot_20220908-102508_Drive.jpg
 
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Ive been running T6 in my Impreza with no issues since I got it from japan(2013).

The valve train is indeed loud at cold startup, but quiets down when it gets warm.

Sample from 2016 @ 4500kms/6 months interval. Ej20k
View attachment 116120
Frisco, your UOA is so fuzzy it can’t be read. Can you just clip the elements & results & repost to see if that clears it up? Very few people on the board even care about Blackstone’s comments (I like them for the laughs) 😂
 
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I'll just throw this in here... if a thick 20 or a thin 30 can be used all year round. Seems something in the 30 range is about perfect.. @Trav made a post about oil pressures at idle with stock oil pump on an EJ that has me wondering about how far the oil grade envelope can be pushed.

If you drive for very very very long times and distances, maybe you want thicker MOFT which could coincide with HTHS? Or as long as it doesn't thin further.. just thinking out loud here.
 
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Might be. But Subarus are not known for piston issues, believe it or not! 😂 Some FBs had bad oil rings, some EJs had HG issues, but pistons & 4EAT issues are generally quite rare.

Toss a 0/5w40 in it (Rotella T6 is always a safe bet) and motor on! 😎
Piston Slap is a known issue on Subaru's as well as many other engines. It is not an inherent problem, more an annoyance. It can cause more ring wear in the long term but changing oil viscosity could counteract that.

“Piston slap is generally caused when the cold running clearance (piston-to-wall clearance) is large enough that when the piston rocks from side to side in the bore it “slaps” the side of the cylinder and causes noise
 
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Piston Slap is a known issue on Subaru's as well as many other engines. It is not an inherent problem, more an annoyance. It can cause more ring wear in the long term but changing oil viscosity could counteract that.

“Piston slap is generally caused when the cold running clearance (piston-to-wall clearance) is large enough that when the piston rocks from side to side in the bore it “slaps” the side of the cylinder and causes noise
Piston slap in a Subaru engine is nothing more than a startup annoyance at worst. Yes, the flat 4 is prone to excessive connecting rod/piston angle. And, it doesn't happen on every one; also, once hot, the issue disappears. So, unless one expects Lexus LS400 smoothness & quietness at 1/4 the cost, it is nothing more than a footnote in history. Piston slap does not affect mileage, power, or durability, so therefore, just as on the LS engines, it is merely an inconvenience.

As a side note, I can't recall the last N/A EJ engine I saw, regardless of mileage, that "failed" because of ring wear. The turbo EJs either last a long time or are condemned to a spun #4 rod bearing if the coolant bypass mod is not completed. Rings (other than 2014 manual FB25s) are very, very rarely an issue on EJ engines.
 
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I'll just throw this in here... if a thick 20 or a thin 30 can be used all year round. Seems something in the 30 range is about perfect.. @Trav made a post about oil pressures at idle with stock oil pump on an EJ that has me wondering about how far the oil grade envelope can be pushed.

If you drive for very very very long times and distances, maybe you want thicker MOFT which could coincide with HTHS? Or as long as it doesn't thin further.. just thinking out loud here.
Schwinney, I don't think anyone has had the sack to try even a thin 20 in their EJ251/253, and certainly not on an EJ255/257. Technically, the Redline 20wt has a high enough viscosity & HTHS to try, but with how old & high mileage the EJs are, few are willing to drop that kind of cash on a 110whp machine, regardless of how bulletproof it is.

I typically just use whatever syn Xw30 or Xw40 I have in my EJ251s; my viewpoint is filtration is paramount here vs. oil quality; at 12+ [email protected] RPM, Subaru is literally washing any wear away from the bearing surfaces & you must then filter it out of the supply to have a long, happy life. I personally don't worry about a little HG oil drip; I may soak the area in brake cleaner & then apply a strip of black RTV to the bottom of the head. Until I get potassium & sodium mixed in the oil, I'm not going to open the engine up. But that's me.
 
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IMHO.

The problem with Subaru, especially newer ones, DOHC, and DOHC turbo models is......Subaru.

Want a Subaru. Look for a sohc older model, do the gaskets, enjoy the low operating cost, awd of it.

As a subie fanboi, that really hurt to type. I need my safespace now.
If you buy a used EJ N/A Subie, be prepared to do HG (properly!) and CV axles. Other than that, it is smooth sailing to 250K!

Turbo EJs are a crapshoot IMHO; I’ve stayed away because EJ255/257 built short blocks are more expensive than building a 600HP LS3… so I ride in the economy lane & smile the whole time!
 
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Piston slap in a Subaru engine is nothing more than a startup annoyance at worst. Yes, the flat 4 is prone to excessive connecting rod/piston angle. And, it doesn't happen on every one; also, once hot, the issue disappears. So, unless one expects Lexus LS400 smoothness & quietness at 1/4 the cost, it is nothing more than a footnote in history. Piston slap does not affect mileage, power, or durability, so therefore, just as on the LS engines, it is merely an inconvenience.

As a side note, I can't recall the last N/A EJ engine I saw, regardless of mileage, that "failed" because of ring wear. The turbo EJs either last a long time or are condemned to a spun #4 rod bearing if the coolant bypass mod is not completed. Rings (other than 2014 manual FB25s) are very, very rarely an issue on EJ engines.
Mine(Forester XT) spun #2 right over 60k, luckily I had an aftermarket warranty and I got SofA to pitch in for repairs considering it was the exact years they issued a stop sale of STI's because of bad bearings. I had a few UOA's done in it's life close to that mileage and not one noted increased bearing wear. All said & done it also toasted both cams in the heads so I almost got a completely new motor. The heads stayed but were reworked obviously. Well over $9k because they wouldn't issue me a free loaner. I had to pay but out of that I spent maybe $1000 out of pocket after everything was said and done since the warranty doesn't pay for consumables. Still loved the car lol.
 
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