I just bought a completely stock 2006 Subaru WRX. It is fast but still pretty slow all things considered. I was told by previous owner he was running 15w-50. Subie forums love 40 weights and I dont understand why. I am running 5w-20 in it,drained out the 15w-50 last week. I keep telling people its a four cylinder motor with very little boost(not a 6.0L turbo charged beast)and it will never see a track,drag strip or cattle trailer. My question is I would like to know everyones opinion, what they would run in theirs. Being as everyone who already has one is running 40 weight or a Redline 30 weight.
20 weight in Subie
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Does the manual specify various weights for the turbo model?
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I'm curious what does the manual say? Also, what is the sump size?
If I used a 20 grade, I would use any good synthetic 5w20. The new Mobil 1 HM 5w20 may be a good choice. Any of the major brand 5w30's would work well.
Mobil 1 0w40 and Rotella 5w40 are great choices in the 40 grade range.
If I used a 20 grade, I would use any good synthetic 5w20. The new Mobil 1 HM 5w20 may be a good choice. Any of the major brand 5w30's would work well.
Mobil 1 0w40 and Rotella 5w40 are great choices in the 40 grade range.
Seems a little thin for a turbocharged engine. Even the turbo Chevy Cruze 1.4 I believe requires 5W30 oil(though I could be wrong).
My 2011 WRX manual specs 5w30 for my car. I'd personally be scared to run that thin of an oil on my turbo Subaru.
My 2011 WRX manual specs 5w30 for my car. I'd personally be scared to run that thin of an oil on my turbo Subaru.
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Originally Posted By: KHP
Seems a little thin for a turbocharged engine. Even the turbo Chevy Cruze 1.4 I believe requires 5W30 oil(though I could be wrong).
My 2011 WRX manual specs 5w30 for my car. I'd personally be scared to run that thin of an oil on my turbo Subaru.
My model year specs the same as yours but I figured a 20 weight would be fine. This is not directed towards you KHP but what the difference does a turbo make? Also in my case the car will never see over 3,000 RPM.
Seems a little thin for a turbocharged engine. Even the turbo Chevy Cruze 1.4 I believe requires 5W30 oil(though I could be wrong).
My 2011 WRX manual specs 5w30 for my car. I'd personally be scared to run that thin of an oil on my turbo Subaru.
My model year specs the same as yours but I figured a 20 weight would be fine. This is not directed towards you KHP but what the difference does a turbo make? Also in my case the car will never see over 3,000 RPM.
I'd at least use a 5-30 full synth.
If ambient conditions and driving were more vigorous, 0-40 M1. This 0-40 is excellent, and my first choice.
If ambient conditions and driving were more vigorous, 0-40 M1. This 0-40 is excellent, and my first choice.
the turbo has high heat in it.. this heats the oil above 212F so it gets really thin and doesnt protect the turbo when driven hard.(and possibly the rest of the engine eventually)
Need a min. viscosity
this is usually a full syn 5w30
but for people who want an extra buffer they run a 5w40.
I'm known for being blunt.. but I'd say you are committing wallet suicide running a 5w20 in a turbo'ed subie
even their NON turbo engines require(d) 5w30 until the switch over to the fb25 starting in 2011-2013
Need a min. viscosity
this is usually a full syn 5w30
but for people who want an extra buffer they run a 5w40.
I'm known for being blunt.. but I'd say you are committing wallet suicide running a 5w20 in a turbo'ed subie
even their NON turbo engines require(d) 5w30 until the switch over to the fb25 starting in 2011-2013
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Subaru specifies a 5w-30 synthetic.
If you wana play with 20 grades, Redline 5w-20 would be my only choice. IMO that is too light for abuse, but if you dont beat on it, the Redline 5w-20 would be fine.
I like to beat on my car. So in non-racing conditions, if I owned a WRX... personally i would run 2qts of Toyota 0w-20 and fill the rest with Mobil 1 0w-40. But for some thats not practical.
So how about for frequent abuse German Castrol 0w-30, Pennzoil Ultra 10w-30, The Amsoil OE or XL 5w-30, Redline 0w-30
Straight Mobil 1 0w-40 would be my first choice for autocross however followed by Rotella T6 5w-40.
If you wana play with 20 grades, Redline 5w-20 would be my only choice. IMO that is too light for abuse, but if you dont beat on it, the Redline 5w-20 would be fine.
I like to beat on my car. So in non-racing conditions, if I owned a WRX... personally i would run 2qts of Toyota 0w-20 and fill the rest with Mobil 1 0w-40. But for some thats not practical.
So how about for frequent abuse German Castrol 0w-30, Pennzoil Ultra 10w-30, The Amsoil OE or XL 5w-30, Redline 0w-30
Straight Mobil 1 0w-40 would be my first choice for autocross however followed by Rotella T6 5w-40.
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gathermewool
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Why did you buy a WRX if you're not going to go past 3k RPM? These turbos only start building boost right before then. IMO, a 2.5i would be more enjoyable and economical (in every single sense) were I the type who kept the RPM's low.
Also, I'll second the viscosity requirement for high temp turbo bearing concerns, as well as main bearings, which were obviously designed for what the manual calls for, which is a range from 5W-30 to XW-40.
With that said, and considering how you seem to want to drive it, I'd say only a very robust XW-20 would suffice. At that point, you might as well have gone with an XW-30, since all it takes is one good, hot run when you're feeling froggy one summer afternoon to damage a bearing. This may NEVER happen, but the mileage hit you'll take between an XW-20 and XW-30 is minimal, and most certainly not worth the risk, IMO.
EDIT: Also, the oil the previous owner was running is even more ridiculous than what you're proposing. The '08 and previous WRX's do NOT need anything nearly that thick, even if it's tracked hard.
Also, I'll second the viscosity requirement for high temp turbo bearing concerns, as well as main bearings, which were obviously designed for what the manual calls for, which is a range from 5W-30 to XW-40.
With that said, and considering how you seem to want to drive it, I'd say only a very robust XW-20 would suffice. At that point, you might as well have gone with an XW-30, since all it takes is one good, hot run when you're feeling froggy one summer afternoon to damage a bearing. This may NEVER happen, but the mileage hit you'll take between an XW-20 and XW-30 is minimal, and most certainly not worth the risk, IMO.
EDIT: Also, the oil the previous owner was running is even more ridiculous than what you're proposing. The '08 and previous WRX's do NOT need anything nearly that thick, even if it's tracked hard.
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Originally Posted By: gathermewool
Why did you buy a WRX if you're not going to go past 3k RPM? These turbos only start building boost right before then. IMO, a 2.5i would be more enjoyable and economical (in every single sense) were I the type who kept the RPM's low.
My thoughts exactly. I bet this car will see drag strip and plenty of WOT runs. I feel as though alot of people have this view on a new to them car initially. I know i did! Told myself i was gonna be responsible and not beat on my Accord. But now its quite modified and i autocross it on the regular.
Why did you buy a WRX if you're not going to go past 3k RPM? These turbos only start building boost right before then. IMO, a 2.5i would be more enjoyable and economical (in every single sense) were I the type who kept the RPM's low.
My thoughts exactly. I bet this car will see drag strip and plenty of WOT runs. I feel as though alot of people have this view on a new to them car initially. I know i did! Told myself i was gonna be responsible and not beat on my Accord. But now its quite modified and i autocross it on the regular.
Well... Pretty much everyone has covered all the bases.
1. High heat as the oil passes turbo causes the oil to thin out.
2. Journal bearings on your crank and Turbo that's spinning at +15000RPMS will be sitting on a thinner film due to hotter oil. Once you hit boost more force is exerted down to the piston to connecting rod and down the Journal bearings. Any metal to metal contact after oil film fails has a high probability of a spun bearing.
1. High heat as the oil passes turbo causes the oil to thin out.
2. Journal bearings on your crank and Turbo that's spinning at +15000RPMS will be sitting on a thinner film due to hotter oil. Once you hit boost more force is exerted down to the piston to connecting rod and down the Journal bearings. Any metal to metal contact after oil film fails has a high probability of a spun bearing.
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+1 on the suggestions made for 5W30 full synthetic.
If it were mine, I'd try out German Castrol 0W30 as well and see how it feels. It is basically a 40wt.
If it were mine, I'd try out German Castrol 0W30 as well and see how it feels. It is basically a 40wt.
Google "turbo Subaru hths oil" and see what you find.
How many miles on your wrx? New it speced 5w-30, and most of those on the market are really not up to the job at hand. Plenty of good suggestions for better choices already in this thread...
How many miles on your wrx? New it speced 5w-30, and most of those on the market are really not up to the job at hand. Plenty of good suggestions for better choices already in this thread...
Subaru knows turbo engines, and Subaru recommended a thirty grade oil with good reason.
Many turbo Subie owners run forty grades with good reason.
Check out the UOA forum.
If you really want to run a twenty in this engine, run it for a reasonable interval and then UOA it.
The engine may be just fine with a twenty grade, although it may not be.
This will depend upon how hot the oil gets as you use the car.
Remember that you are going thinner than what Subaru recommended.
Does the WRX have an oil pressure gauge?
Would be nice to know what kind of oil pressure the twenty grade oil is providing.
Finally, why even have a WRX unless you're going to jump on it every now and then?
If you aren't, you may as well have a Civic and enjoy better fuel economy.
Many turbo Subie owners run forty grades with good reason.
Check out the UOA forum.
If you really want to run a twenty in this engine, run it for a reasonable interval and then UOA it.
The engine may be just fine with a twenty grade, although it may not be.
This will depend upon how hot the oil gets as you use the car.
Remember that you are going thinner than what Subaru recommended.
Does the WRX have an oil pressure gauge?
Would be nice to know what kind of oil pressure the twenty grade oil is providing.
Finally, why even have a WRX unless you're going to jump on it every now and then?
If you aren't, you may as well have a Civic and enjoy better fuel economy.
15W50????? thats just craaaazayyy. use whats advised.
XW-50 is an approved viscosity for this vintage Subaru. Read the manual.
Ed
Ed
Why not use what's worked well for so many turbo Subie owners before you? GC 0w-30, M1 0w-40, or my personal choice Rotella T6. The Subie guys love Rotella, but I haven't seen a thread bragging about how long a turbo lasted on 20wt. You're taking a heck of a chance.
Originally Posted By: edhackett
XW-50 is an approved viscosity for this vintage Subaru. Read the manual.
Ed
Funny how Xw-20 is not on the list...
XW-50 is an approved viscosity for this vintage Subaru. Read the manual.
Ed
Funny how Xw-20 is not on the list...
M1 0w40 at walmart in 5qt jugs, use it! or something thicker than a 20wt. 20wt oils have their place, even on a hot rod (mustang GT, Cobra) but not in a turbo engine.
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