best oil for turbo Subaru

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What is the best oil to use for a 2006 2.5l 4cyl, 70K miles, Subaru Legacy? Manual and service dept say to use conventional oil, but I feel synthetic would be best. Also any spcific quirks about this engine. Thanks
 
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You don't have to use a Subaru Oil Filter, but a quality 5W-30 synthetic oil that meets the Honda HTO-06 spec is wise.
 
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Many will suggest Rotella T6 5w-40, although personally I think its a bit of overkill. If you drive hard/track autoX, consider it. I've run the following in my LGT: PU 10w-30 Castrol Edge 0w-40 M1 0w-40 M1 TDT (I got it cheap) You want an oil that will resist shearing. Pennzoil ultra seems to hold up for lots of folks. T5 syn blend has a HTHS of 3.5 and should fair well too. I stick to ~4500-5000 OCI, and I use a subaru filter. (Search bypass PSI and decide for your self) If running a Dino, I'd change at 3500. (Unless it is 10w-40.)
 
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My experience using dino and 3500 mile OCI over 170k+(2005 LGT) has been really good. A recent valve burn(unrelated to oil) lead to full engine removal to rebuild the heads. Internally the pistons and everything else were excellent condition along with the OEM turbo having no free play. Not very much varnish either. I had the banjo bolt replaced but the filter was not even that dirty either. I am going to go on a limb and say Subaru is correct.
 
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Rotella T6 5w-40 Mobil 1 TDT 5w-40 Mobil Delvac 1 5w-40 Mobil 1 0w-40 Castrol Edge 0w-30 or 0w-40 Take your pick and use a Subaru or Wix filter for 5,000 mile changes.
 
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Oil - Quality synthetic in a 0/5W30/40 Filter - OEM or Wix 57712 to meet Subaru's unusually high bypass spec I wouldn't run convention more than 3000-4000 in this engine, the turbo gets hot. Synthetic should be good for 5000-7000. 5000 if you don't want to do any analysis and want a safe number. My personal oils would be QSUD 5w30, Rotella T6 5w40, or Mobil1 0w40.
 
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Originally Posted By: Hollow
Oil - Quality synthetic in a 0/5W30/40 Filter - OEM or Wix 57712 to meet Subaru's unusually high bypass spec I wouldn't run convention more than 3000-4000 in this engine, the turbo gets hot. Synthetic should be good for 5000-7000. 5000 if you don't want to do any analysis and want a safe number. My personal oils would be QSUD 5w30, Rotella T6 5w40, or Mobil1 0w40.
So all those big rigs with their diesels and huge turbos using conventional should worry about their turbo getting hot then,since your using that as some sort of reason not to use a conventional. Turbos get hot everywhere they are fitted. Using hot exhaust gasses to spin an impeller will do that pretty effectively,yet even those big rigs,and diesel trucks out there who run mileages sky high,on conventional oil,and their turbos last just fine. See where I'm going here....... OP. Try a Subaru forum and read what they've got to say and pick some guys brains here. Use the used oil analysis section as a tool as well. See how long the oil lasts by reading the tbn,which is basically what necessitates an oil change. Don't just follow an interval by cause some guy on the internet thinks it's a good idea because he's "never had any problems" Acquire data. Use that data to make an informed choice.
 

rryam

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The reason big rigs can use dino oil with Their turbos with no problems is they have great big oil coolers....and their oil capacity is measured in gallons,not quarts.
 
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I don't know if you have the room for this filter but a Baldwin B202 with a 20 # psid by-pass valve or a B7042 with a 14 # psid valve would be a good choice. Both filters are 3 11/16" X 5 3/8", I've ran both on my S2000. ROD
 
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Originally Posted By: Clevy
Originally Posted By: Hollow
Oil - Quality synthetic in a 0/5W30/40 Filter - OEM or Wix 57712 to meet Subaru's unusually high bypass spec I wouldn't run convention more than 3000-4000 in this engine, the turbo gets hot. Synthetic should be good for 5000-7000. 5000 if you don't want to do any analysis and want a safe number. My personal oils would be QSUD 5w30, Rotella T6 5w40, or Mobil1 0w40.
So all those big rigs with their diesels and huge turbos using conventional should worry about their turbo getting hot then,since your using that as some sort of reason not to use a conventional. Turbos get hot everywhere they are fitted. Using hot exhaust gasses to spin an impeller will do that pretty effectively,yet even those big rigs,and diesel trucks out there who run mileages sky high,on conventional oil,and their turbos last just fine. See where I'm going here....... OP. Try a Subaru forum and read what they've got to say and pick some guys brains here. Use the used oil analysis section as a tool as well. See how long the oil lasts by reading the tbn,which is basically what necessitates an oil change. Don't just follow an interval by cause some guy on the internet thinks it's a good idea because he's "never had any problems" Acquire data. Use that data to make an informed choice.
I'm on the subaru forums. Small sump on a crammed in turbo engine for longer intervals on conventional will get you a new turbo at best and a new engine at worse. If you actually researched anything I said, on any Subaru forum, you would find I speak the consensus. Thanks for dismissing me out of hand though.
 
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Originally Posted By: rryam
The reason big rigs can use dino oil with Their turbos with no problems is they have great big oil coolers....and their oil capacity is measured in gallons,not quarts.
Yes, and with Delvac or Rotella TripleT, you have enough HTHS to run a conventional oil. Not many big rigs are running a 2.9-3.0 HTHS 5w-30.
 
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Back in the early to mid 2000's, I owned a 2003 Mitsu Evo VIII. The car was sold in excellent condition with over 175K miles, all on dino. And oils have only gotten better since... API Engine Oil Service Category Charts Gasoline Engines as "S" SN ---Introduced in October 2010 for 2011 and older vehicles, designed to provide improved high temperature deposit protection for pistons, more stringent sludge control, and seal compatibility. API SN with Resource Conserving matches ILSAC GF-5 by combining API SN performance with improved fuel economy, turbocharger protection, emission control systemcompatibility, and protection of engines operating on ethanol-containing fuels up to E85.... LINK: http://www.oilspecifications.org/api_eolcs.php If specs allow, Conventional oil is definately an option if not tracked and short oci employed.
 
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Originally Posted By: Bandito440
Rotella T6 5w-40 Mobil 1 TDT 5w-40 Mobil Delvac 1 5w-40 Mobil 1 0w-40 Castrol Edge 0w-30 or 0w-40 Take your pick and use a Subaru or Wix filter for 5,000 mile changes.
This is what I would do if I had a turbo Subaru, though I might push it 6k miles.
 
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Originally Posted By: rryam
What is the best oil to use for a 2006 2.5l 4cyl, 70K miles, Subaru Legacy? Manual and service dept say to use conventional oil, but I feel synthetic would be best. Also any spcific quirks about this engine. Thanks
The manual says 5W-30 is preferred. Rotella 5W40 has a large fan base in the Subaru community. I split the difference and use Mobil1 0W40 in my 2005 LGT. The Subaru OE oil filter has a 23psi bypass valve. There are a billion threads debating whether this bypass psi is critical or not.
 
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Originally Posted By: rjundi
My experience using dino and 3500 mile OCI over 170k+(2005 LGT) has been really good. A recent valve burn(unrelated to oil) lead to full engine removal to rebuild the heads…………………..
What condition caused the burnt valves?
 
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Originally Posted By: Hollow
Small sump on a crammed in turbo engine for longer intervals on conventional will get you a new turbo at best and a new engine at worse.
Nonsense. You just can't lump every single conventional oil together. Of note, there are many small sump turbo owners out there running 15w-40 (Delo, Delvac, Rotella) with great success.
 
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Originally Posted By: rjundi
My experience using dino and 3500 mile OCI over 170k+(2005 LGT) has been really good. A recent valve burn(unrelated to oil) lead to full engine removal to rebuild the heads. Internally the pistons and everything else were excellent condition along with the OEM turbo having no free play. Not very much varnish either. I had the banjo bolt replaced but the filter was not even that dirty either. I am going to go on a limb and say Subaru is correct.
rjundi, Just noticed yours is a wagon. In my opinion, the nicest Legacy ever made. It and the Mitsubishi Galant VR4 are the ones that got away from my bucket list lol.
 
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Subaru of America now recommends synthetic on pre-2011 turbos that did not originally require it. Surprised that a dealer would not know this. My dealer just added a nice "synthetic oil only" sticker to my engine bay after my valve job. Ok, it's kinds cheesy. http://drive.subaru.com/spr11_whatmakes.aspx "For 2010 and earlier turbocharged engines, Subaru also recommends the Subaru synthetic 5W-30 motor oil." Yes, your best bet is to run a NON Resource Conserving synthetic as others have recommended above. Check Legacygt.com for things like bearing failures as well as turbo failures due to clogged AVCS and turbo banjo bolt screens. Or just listen to the advice of the Subaru turbo owner's here! OT (actually on topic since the OP could be affected). SubLGT - I just had a valve job on my FXT as well. More reading here: http://allwheeldriveauto.com/seattle-area-subaru-burnt-exhaust-valve/?no_redirect=true -Dennis
 
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