Originally Posted By: 94exa2
Turbo. "stage 2" 2005 Wrx.
Yeah I figured this would be the best site to ask, since most car forums are just walking advertisements for whatever brand is "in" at the time.
I read Mobil1 isn't a "real" synthetic, being a group 3?
And Royal Purple, Amsoil and Redline with a couple others are "real" synthetics being group 4 or 5.
But I read a bunch of bad posts about Mobil1 and Royal Purple specifically in the Wrx crowd.
And it seems that most car enthusiasts recommend either Amsoil or Redline. Good choices? One better than the other? I know one is a group 4 and the other is a 5, but not sure which, or which is better.
I think I would most likely avoid 0w-anything, but am curious if I should go with 5w40 since it seems alot of Wrx owners complain about "thin oil" and "eating oil up" lol.
Where are you reading this stuff? I-club or nasioc? A few of us at nasioc try to educate people, but sometimes it's a tough fight.
First, forget about base stocks. Many "synthetic" oils these days contain a blend of Group III, IV and/or V base stocks and/or additives and Group III's have really narrowed the gap in performance over the past few years. The much loved Rotella T6 is Group III. There's even speculation that some synthetic base stocks or additives are being used in some conventional oils because they're meeting some amazing specs.
Secondly, Royal Purple and Mobil1 get a bad rap when someone runs the 5W-30 in a Subie turbo and has a bearing failure or does a uoa and the oil has sheared to a 20 grade or is contaminated from fuel. Of course, state of tune, checking the oil regularly and using the proper viscosity for the application are very important. News flash! Both Mobil1 and Royal Purple make more than just Resource Conserving 5W-30! The same goes for Amsoil. Stick with the robust oils if you go with Amsoil. HDD 5W-30, DEO 5W-40, or EFM 5W-40.
My advice is to switch to synthetic which is recommended by Subaru of America for all turbos. If you're paranoid about gasket or seal leaks, Mobil1 High Mileage is a good choice. These oils are a bit more robust in viscosity, High Temp High Shear, and the additive package than the other Mobil1 oils. 10W-30 and 10W-40 are the most robust among the M1 High Mileage oils and 10W-30 and 10W-40 is allowed down to -4F according to your owner's manual (a couple of folks above got it right!). Notice the cap states "See Manual". The manual says 5W-30 is preferred for fuel economy and thicker viscosity is required in hot weather and/or severe conditions.
Basically, many Subaru turbo enthusiasts prefer non-Resource Conserving oils because they are more robust. Mobil1 0W-40, Rotella T6 5W-40, and German/Belgian Castrol 0W-30/0W-40 are favorites because they're easy to find (except maybe GC/BC depending on your location).
With all that said, the newer GF-5 5W-30 oils (especially Pennzoil Ultra) are showing some good uoa results in some conditions (eg stock WRX, mainly highway miles) but I would go with a more robust oil since you are Stage II, especially if you are not protuned. E-tunes and Off The Shelf tunes usually have more fuel contaminating the oil cause they run rich for safety.
How long has the car been Stage II? Open source, e-tune, or AccesPort? I'm guessing the previous owner did short intervals of 3k miles or less.
-Dennis
Turbo. "stage 2" 2005 Wrx.
Yeah I figured this would be the best site to ask, since most car forums are just walking advertisements for whatever brand is "in" at the time.
I read Mobil1 isn't a "real" synthetic, being a group 3?
And Royal Purple, Amsoil and Redline with a couple others are "real" synthetics being group 4 or 5.
But I read a bunch of bad posts about Mobil1 and Royal Purple specifically in the Wrx crowd.
And it seems that most car enthusiasts recommend either Amsoil or Redline. Good choices? One better than the other? I know one is a group 4 and the other is a 5, but not sure which, or which is better.
I think I would most likely avoid 0w-anything, but am curious if I should go with 5w40 since it seems alot of Wrx owners complain about "thin oil" and "eating oil up" lol.
Where are you reading this stuff? I-club or nasioc? A few of us at nasioc try to educate people, but sometimes it's a tough fight.
First, forget about base stocks. Many "synthetic" oils these days contain a blend of Group III, IV and/or V base stocks and/or additives and Group III's have really narrowed the gap in performance over the past few years. The much loved Rotella T6 is Group III. There's even speculation that some synthetic base stocks or additives are being used in some conventional oils because they're meeting some amazing specs.
Secondly, Royal Purple and Mobil1 get a bad rap when someone runs the 5W-30 in a Subie turbo and has a bearing failure or does a uoa and the oil has sheared to a 20 grade or is contaminated from fuel. Of course, state of tune, checking the oil regularly and using the proper viscosity for the application are very important. News flash! Both Mobil1 and Royal Purple make more than just Resource Conserving 5W-30! The same goes for Amsoil. Stick with the robust oils if you go with Amsoil. HDD 5W-30, DEO 5W-40, or EFM 5W-40.
My advice is to switch to synthetic which is recommended by Subaru of America for all turbos. If you're paranoid about gasket or seal leaks, Mobil1 High Mileage is a good choice. These oils are a bit more robust in viscosity, High Temp High Shear, and the additive package than the other Mobil1 oils. 10W-30 and 10W-40 are the most robust among the M1 High Mileage oils and 10W-30 and 10W-40 is allowed down to -4F according to your owner's manual (a couple of folks above got it right!). Notice the cap states "See Manual". The manual says 5W-30 is preferred for fuel economy and thicker viscosity is required in hot weather and/or severe conditions.
Basically, many Subaru turbo enthusiasts prefer non-Resource Conserving oils because they are more robust. Mobil1 0W-40, Rotella T6 5W-40, and German/Belgian Castrol 0W-30/0W-40 are favorites because they're easy to find (except maybe GC/BC depending on your location).
With all that said, the newer GF-5 5W-30 oils (especially Pennzoil Ultra) are showing some good uoa results in some conditions (eg stock WRX, mainly highway miles) but I would go with a more robust oil since you are Stage II, especially if you are not protuned. E-tunes and Off The Shelf tunes usually have more fuel contaminating the oil cause they run rich for safety.
How long has the car been Stage II? Open source, e-tune, or AccesPort? I'm guessing the previous owner did short intervals of 3k miles or less.
-Dennis
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