Oil for a Subaru F4 turbo?

[DrD]

Ok - so I have searched a bit, and saw the big Subaru spreadsheet,in this thread
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1293170#Post1293170
and am still uncertain if there is a clear frontrunner for the subaru engines (I have an 02 WRX, so the 2l turbo) - my experience has been that almost without exception, most oils seem to hold their own for a little while, then start to rapidly fall off (in level - burnt/blow by/etc.) - the worst results I had (in terms of when the oil started going away) were with M1 - both for 5w30 and 10w30 - probably 1k miles or so in, and the volume would start to drop. RP 10w30 and 10w40 tend to go 2k miles or so, then start dropping - same deal with Redline 10w40. When I look at the spreadsheet, I don't see any clear trends in viscosity dropping off or anything like that which correlate with my experience - the oil analyses don't really say anything about how the car was driven, either, so there's that, too. I typically do all city driving, and alot of that is probably "spirited". I have typically changed around 2.5-3k miles (when I notice volume really falling off) - haven't done an oil analysis, though. (I've always figured something has changed, so I dump it - cheap insurance in my book, to protect against me forgetting to keep an eye on the level after 2k miles and running dangerously low)

Has anyone else out there taken a look at that data and have any thoughts? Are there any other good oils to try? (M1, RP, and Redline are all readily available, so that's what I have stuck to - I have RP 10w40 in there now)

I was sort of surprised that the data didn't show any clear frontrunners (or cellar dwellars) given the seemingly fanatical posts which I have seen on boards like NASIOC claiming M1 and RP are junk.

 

[rg200amp]

You have tried some top preformers.
Perhaps the issue is with your car not the oil???

Have you tried Pennzoil Platnium?


Whenever you change oils, most of the time people see oil usage. Stick to one oil for 2-3 Oil changes then make a proper judgment.


WRXs are very fun!!!

and Welcome to BITOG!

 

[DrD]

Hi - thanks for the reply

I haven't tried penzoil - maybe I will give that a go when it's time to replace the current fill.

I don't think it's anything specific to my car - compression is good (and very uniform - within 2psi across all four cylinders), I don't see excess soot buildup or smoke out the tailpipe, and there is no abnormal oil buildup in the intercooler (not enough to even form a drip or pool anywhere that I have seen - plus the throttle body looks very clean). Plugs looked good when I changed them last year. PCV valve is in good shape, etc. as well - fuel economy is pretty typical, and really hasn't changed over the 6 years I've owned the car.

 

[bluesubie]

Hey, it's DrD from nasioc.

I've never had more than 1 qt. of consumption using GC, Motul 8100 5W-30 or Amsoil SSO 0W-30. I've actually gone 7,500 miles on GC without having to add any make-up oil. These cars do vary greatly on oil consumption though. I think my conditions are pretty tough (occasional towing, daily short trips, off-roading, etc.) so I don't think my consumption is that bad. Here's my last SSO UOA.

I'm guilty of attacking RP, especially after those 10W-30 uoa's on nasioc where it sheared to a 20 grade in less than 4k miles in one case and 1,100 in another.

For consumption in an '02, I would seriously consider running a diesel 5W-40.

-Dennis

 

[SuperEd73]

DrD,

I also have an '02 WRX. I bought it brand new in 4/2002. It now has about 94,500 miles on it. I've definitely experienced the same results as you have using different oils. I have tried PP 5W-30 and it started to eat oil around 2500-3000 miles into the OCI. From what I've read, the Subie turbo engines shear the 30W oils down to a 20W pretty rapidly. So, now I'm trying some Rotella Synthetic 5W-40. Relatively cheap and pretty easy to find. I know some people have used German Castrol with various results. I did have to add about 1/2 quart recently and that's about 2300 miles into the current OCI. One other thing I've noticed that the Rotella seems to look much darker now than when I first poured it into the engine. Not sure why. If my wallet permits, I'll have a UOA performed to see how well the viscosity holds up.

Ed B.

 

[WolfPlayer]

I'm sold on Renewable Lubricants 5W-40HD. I've used it for the past 12K miles on my modified 2005 STI.

http://www.bescaredracing.com/sti/oil/analysis/

t

 

[scoobie]

just keep changing it at 2.5 to 3 k miles. it sounds like the way you are driving, that if you want your engine to last, then just change it out regularly. if it's a pain, get a fumoto valve, you won't even need to get a wrench out to do it. Modern dino oils are made to withstand turbos, but i would recommend a synthetic
15w40. with you living in new mexico, 15w40 will not be too thick, and should protect your engine well. you may even get a 4000 mile interval with it. i've checked my subie manual and they do allow heavier oils where conditions allow. also, a 15w40 synthetic will still pour a lot nicer than a comparable dino, and would also be preferable to a 20w50. so my bottom line is 15w40 synthetic of any make that you can find.

 

[HitManX]

I bought my '02 WRX new and kept until about 45k miles I guess it was... sometime in '04/5 I sold it. I ran M1 5/30 the entire time I had it. Just a few mods like full exhaust, Unichip, VF34, etc. I guess that is quite a bit but far from radical.

At the time I was going with 5k drain intervals with 2500 swapping the filter then topping up accordingly. I had no consumption issues during that time and no issues with the car, ran great.

Since then I have purchased some other factory turbo vehicles and it seems that they are better off with ?W40, at least an HD oil or a good quality Synthetic.

 

[Titan]

Originally Posted By: HitManX
I was going with 5k drain intervals with 2500 swapping the filter then topping up accordingly.


Stick around and read more, you'll find you should have left the filter on the entire 5K, since filters work better and better the longer they are on. Within reason, of course. I ran Wix filters on my Subarus up to 15,000 miles, with stellar UOA's and insoluables at 0.2...that's darn good filtration.