New 2015 WRX, new oil?

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So, I just picked up my new 2015 WRX (6mt) and am trying to figure out which oil to go with. I still have half a case of Redline 5w30 left over from my prior car (370z). Is there any reason not to stick with redline?

I emailed Subaru and they said they don't recommend any brand, only that I stick with 5w30.

I live down here in Houston (read HOT). My commute to work is mostly highway, but my trip home usually includeincludes 20-30 minutes sitting in stop and go (mostly stop) traffic. Anticipate sticking with my 3-3.5k oil change interval.

From what I've read, wrx's are [censored] on oil. I'm hoping to run the wrx till the wheels fall off. (Was the plan for the Z as well, but problems unfixable by dealer and an unexpected addition to the family changed that).
 
That car has a new engine, so you would be best off comparing it to the 2014+ forester 2.0XT

Although the wrx engine does have some tweaks over the forester.

Conventional Subaru wisdom would have you using rotella T 5w40 in it.

This engine has no resemblance to the -2014 wrx though. Unless you are taking it to the Track or auto-rx a good 5w30 should be fine. M1 0w40 is another excellent choice, barely a 40wt it usually shears to a heavy 30wt.

I'm not a fan of Redline engine oils the value/dollar just isn't there, although I do like their transmission products. I don't think the Redline oil would hurt anything of course.

Just that a 5qt jug at walmart for <25$ would provide similar performance.
 
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to BITOG!

If you have an official email from Subaru saying you can use any 5w-30, then I'd imagine you'll be fine on the warranty front, though I'd double-check that.

I'd go for either Subaru-branded oil or something with third-party approvals myself, but I see no reason not to use the Red Line you already have.
 
the redline will be fine to use up, after that as mentioned, any of the other 5w-30 synthetic oils you can buy at wally world for a great price will work just as good for that short an interval change.
 
It wasn't mentioned but these cars spec a full syn 5w30, and a 6000mile oci, 3000mile severe service interval.

IIRC they also have a larger sump than the -2014 engine which helps keep oil temps from spiking in normal use.
 
If you tell SoA that you have Red Line, they would probably tell you not to use it since it is not API certified.

What some folks that are doing that want to run a more robust oil (robust HTHS and kinematic viscosity) is to run a Euro 5W-30. Oils like Motul X-clean and Mobil 1 ESP 5W-30 are mid-SAPS oils in case you have a worry of valve deposits from the DI (lower SAPS oils are shown to cause less valve deposits).

Even though it's not in the owner's manual you will still always see recommendations for M1 0W-40 and Rotella T6 because WRX's are hard on oil like you said (both the EJ engine and new FA engine). Subaru Japan allows 5W-40 even in the BRZ, which specs 0W-20 in the U.S. SoJ has a Subaru labeled Castrol SLX Professional 5W-40.

Both the new WRX and the new DIT Forester XT are showing some nasty fuel dilution. I've seen numbers from 3% in a Stage I WRX (nasioc) to 6% in a stock Forester XT (this forum).

If you go by the book, then just run any GF5 oil and change at 3,000 miles max. Also, keep every oil receipt and also log it at MySubaru. If you do ANY engine mods (this includes "just a reflash"), I would highly recommend not running a GF5 oil.

-Dennis
 
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Seeing how this is a new to 2015 engine and you have few to no other UOAs from fellow members to go by, I suggest running several top tiered synthetics (preferably from Walmart so prices for you stay low.) and perform UOAs on each one.

Then go with the one that looks best on paper.
 
Thanks for all of the replies. I'm thinking either stick with the Redline or switch over to PU just to get extra assurance of API certs.

I'll try to post my letter to Subaru and their reply later (my mail server is down).


As for the Z, it developed a horrible rattle at about 18k that the dealer couldn't seem to fix. Not a "yeah, that's an annoying" interior rattle. It was a "[censored], sounds [censored] is falling off my car" exterior rattle. Embarrassing pulling up to a light in a fine looking sports car that sounds like a 1982 Trans Am.

Visit 1: dealer went all over the underside of the vehicle. torqued every bolt there. Couldn't fix it. Had me pick it up while they made an appointment with the Nissan engineer.
Visit 2: engineer gave a list of things to check before he came out. Dealer went all over the inside of the car taking trim out. Narrowed it down to seatbelt retractor rattling in the frame. Sent to body shop to check welds. Body shop said they could see the problem, but couldn't figure a fix
Visit 3: engineer and dealers 370Z/GTR guy spent most of a day working on it. Sent it back to body shop to redo weld on frame. No fix. Said they would have engineer back out in 60 days or so for another go.

After them having my car for almost 4 weeks on and off, and 60 days to get it back in again, I was getting sick of messing with it. With family changes making a two seater a pain and my wife always afraid I was going to die in it (most died in vehicle on the road) I decided to ditch it. Didn't meet requirements for lemon law. WRX is actually more fun 90% of the time.
 
I haven't seen anything in a while, but Subaru used to recommend letting your vehicle idle for 30 seconds before turning it off to allow the oil to continue to circulate to help cool off the turbo. Even though I haven't seen them say that in a while, I'd do it whenever possible, especially if the vehicle had just been driven in a spirited manner.
 
Turbo timers are so 80's
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I am not sure about the FA engine design but the EJ's used a gravity based system that helped coolant circulate around the snail after shutdown.

Oil and water cooled turbos are far more advanced then folks give them credit for: its pretty hard to cook them.

The recipe is to abuse them and use substandard oil that goes out of grade, which to the OP's point: use a API certified 5/30 that is stable. Lots of good ones to choose from. I run PU 5/30 in my Z car (also known to be harder on oil, mine is a roadster and no such rattle: I feel you there) and its been stout.

The 5/40 thing on the EJ's is a lot of noise. You are starting with an oil that will shear into a 30w typically vs a 30w that ends in a 20w. Many, many, many EJ's work fine. My 2.0 ran 5/30 for 140K happy miles on original everything: I switched to a M1 0/40 more because it was there and matched some other cars in the fleet. Its also a rather 'light' 40w. T6 is just a very good oil, so it works too. 40w is not required.

A 3K severe OCI, you can use just about anything. With 6K go with something 'better'. Be sure to use the full powerband, that's what its there for
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- b
 
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Almost any modern turbo car uses a thermo syphon setup so that natural convection continues to cool the turbo bearing even after shutdown...
 
you can't go wrong with redline if you don't mind the cost. i ran Amsoil now signature series 10-30 in my modified to 275 hp + 300 TQ 1.8T VW. you might want want to put 5,000 miles on it before using a real synthetic, until then pennzoil platinum from GTL technology would do well. its a group III fake synthetic oil, actually highly refined product, again 10-30. you don't need a 5w in your climate. the wider spread in #'s means more VII in group III + down, real synthetic group IV + V are a different animal for sure
 
I'm fairly sure my rattle was an anomoly. The Nissan dealer was one of the better ones. Never got the impression they were anything but honest and competent. I just got unlucky.

BVL is right on the turbo timer from what I researched. I didn't understand the workings, but Subaru uses coolant to cool the turbo after shutoff. After losing a turbo on my 2007 MazdaSpeed, that was one of my first concerns.

Thinking PU 5w30 is the way to go. May do a few oil analysis for peace of mind. My offer the Redline around and see if anyone at work wI'll take the a redline off my hands to get it out of the Garage.

Thanks all!
 
Originally Posted By: punkndisorderly
Out of curiosity, why wait till 5k to go full synthetic? I thought factory fill was anyway.

It is.
 
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