Picked up some Subaru Synthetic 5w-30

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My new WRX has almost 1500 miles on it now, and I figured this weekend would be a good time to dump the factory fill. I've been agonizing a bit over oil choices, but based on what I've read about Subaru's bypass valve specs was pretty set on using an OEM oil filter. Went by the dealership this morning to pick one up and found out that Subaru's new house branded synthetic oil was actually a reasonable price (not an "on sale" price but about equal to the normal retail price for any decent synthetic around here), not what I expected. I ended up just getting 5 quarts of that for the first change. I'll probably run it 5k miles or so, I guess. I'm a little torn because everyone seems to love Rotella 5w-40 in these engines, but the 2011 owners manual just calls for 5w-30. I'm not sure what's "best" yet but I'm a little uneasy about deviating too much while under warranty. The only mention of 5w-40 in the manual is in a little blurb that basically says you can top off with 5w-30 or 5w-40 conventional in a pinch, but should change to 5w-30 syn at the next oil change. I figured the Subaru branded stuff is an easy default choice. Hopefully I can rest easy with it for a while!
 
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Well of course you can rest easy. Rotella T6 is thicker than necessary for any street driven, unmodified Subie. BTW, I'd be interested in seeing a picture of the bottle of the Subaru Brand 5W-30 if you could post it. What I'm interested in, is it made for them by Idemitsu like their 0W-20 is; Idemitsu uses the same bottle shape for everything they bottle.
 
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I would leave the factory fill in a bit longer since it has much hIgher levels of moly and slightly higher levels of zinc than the dealer service oil. Yes, the 5W-30 is also made by Idemitsu and the SM oil isn't anything special for the price, IMO. There's no way I would leave it in for 7,500 miles as SoA recommends. There have been a couple of decent Energy Conserving uoa's from WRX's popping up, but not much long term data because people chicken out and go with something more robust. One guy on nasioc had a dealer tell him that Rotella caused misfire codes because it was not an approved viscosity (even though the engine hasn't changed on the WRX from the thicker viscosity recommendations at the begining of the model year and was superseded with an addendum). The dealer did an oil change to 5W-30, charged the guy $100, and now he has a check engine light again. http://forums.nasioc.com/forums/showthread.php?t=2251792 I'm still looking for some "5W-40 conventional", which is only allowed for top offs. -Dennis
 
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Originally Posted By: CATERHAM
BTW, I'd be interested in seeing a picture of the bottle of the Subaru Brand 5W-30 if you could post it.
A quick google image search comes up with this:
 

rationull

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Here are some pics of the bottle, as bluesubie says it's made by Idemitsu (please forgive the bad picture quality and lighting!): Edit: Beaten to the punch by Quattro Pete!
 
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rationull

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Originally Posted By: bluesubie
I would leave the factory fill in a bit longer since it has much hIgher levels of moly and slightly higher levels of zinc than the dealer service oil. Yes, the 5W-30 is also made by Idemitsu and the SM oil isn't anything special for the price, IMO. There's no way I would leave it in for 7,500 miles as SoA recommends. There have been a couple of decent Energy Conserving uoa's from WRX's popping up, but not much long term data because people chicken out and go with something more robust. One guy on nasioc had a dealer tell him that Rotella caused misfire codes because it was not an approved viscosity (even though the engine hasn't changed on the WRX from the thicker viscosity recommendations at the begining of the model year and was superseded with an addendum). The dealer did an oil change to 5W-30, charged the guy $100, and now he has a check engine light again. http://forums.nasioc.com/forums/showthread.php?t=2251792 I'm still looking for some "5W-40 conventional", which is only allowed for top offs. -Dennis
I was under the impression that the factory fill was nothing special. Wouldn't extra moly showing up in a factory fill UOA just be attributed to assembly lube or something? I thought I'd seen a pair of UOAs earlier, factory fill and one more OCI, on the Subaru synth but I can't find it anymore and I may be remembering incorrectly. I'm not sure whether I'll stick with this oil for more than one more OCI or not, but it seemed like a good default choice. It may not be anything special for the price but it's cheaper than any other decent synthetics at the local auto parts stores here (not counting sales). That story about the dealer giving somebody grief about Rotella is why I'm leery of going with a 5w-40. Obviously it would be fine for the car, but it seems like sticking with 5w-30 is safer for the warranty "just in case." I've got a lot of driving coming up in another week, so I can either change it out this weekend at 1500-1600 miles or wait a couple weeks and change it out at 2300 miles or so. You still think I should leave it in? Originally I was going to leave it in for 2k miles or so but then I started to get the itch smile I'm not planning to do 7500 mile OCIs, btw, unless I get confirmation from UOAs. I know these engines aren't super easy on oil (a big change from my Civic!) -- I'm planning to do 5000 mile changes on decent non boutique synthetics.
 
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Several years ago, someone from the SIA plant posted on nasioc that they used regular mineral oil and that moly from uoa's was indeed probably from the assembly lube. SoA has also stated that there was no special break-in oil. But when a fellow BITOG'er emailed ILA recently about the Subaru 0W-20, this was their response:
Quote:
OEMs specify Moly in their factory fill formulations to increase fuel economy during the initial period. In general a factory fill formula will be more robust in the additive treatments etc. This is done for a variety of reasons which I will not go into here. Some of the service fill formulations also contained molybdenum however, with  the transition to the ILSAC GF-5 specification, most 0W-20 service fill 0W-20 formulations now do not have Moly.
IIRC, the zinc level of the FF is right around 1,000 ppm's. It's funny how the early oil didn't even show the API spec. -Dennis
 

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Well, gives me something to think about. I'm sure it'd be fine either way, but I just figured if I got the new oil in sooner rather than later I'd feel better about driving the car in a more, uh, spirited fashion smile
Originally Posted By: Quattro Pete
But you posted more detail. smile How are you liking the car so far?
I'm loving it. In truth I'm still a little torn because buying it wasn't the most fiscally conservative thing I've ever done, but it's an upgrade in nearly every way from my Civic and longer term I'm sure I'll be more satisfied with it. I've never actually had a DD with 4 or 5 doors before and it's a nice change. Taking a bit for me to adjust from the "easy on any gas, easy on any oil" character of the Civic but that's all part of the fun smile I like that it feels more like a "real machine" and is more interesting from a mechanical standpoint.
 
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Originally Posted By: CATERHAM
BTW, I'd be interested in seeing a picture of the bottle of the Subaru Brand 5W-30 if you could post it. What I'm interested in, is it made for them by Idemitsu like their 0W-20 is; Idemitsu uses the same bottle shape for everything they bottle.
I think it is the same bottle design that BP, NAPA and the old Honda oils came in. I think a lot of companies use it.
 

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bluesubie: Is the theory that if the break-in oil is indeed different, the engine won't wear in as well with something lower in moly/zinc? Wouldn't 1000 miles be enough? I followed the "don't change the oil until the first scheduled change" recommendation with my last car (07 Civic) and even followed the recommendation and left the factory filter on for 2 OCIs. Car ended up being an oil burner. I'm not blaming that on the OCI but I'm feeling a little more conservative this time.
 
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Originally Posted By: bluesubie
Several years ago, someone from the SIA plant posted on nasioc that they used regular mineral oil and that moly from uoa's was indeed probably from the assembly lube. SoA has also stated that there was no special break-in oil. But when a fellow BITOG'er emailed ILA recently about the Subaru 0W-20, this was their response:
Quote:
OEMs specify Moly in their factory fill formulations to increase fuel economy during the initial period. In general a factory fill formula will be more robust in the additive treatments etc. This is done for a variety of reasons which I will not go into here. Some of the service fill formulations also contained molybdenum however, with  the transition to the ILSAC GF-5 specification, most 0W-20 service fill 0W-20 formulations now do not have Moly.
-Dennis
Thanks for posting this. That's another reason to stock up on the SM version of the oil while it is still available. Another member has already sent off a VOA sample of the SN GF-5 version of the Toyota 0W-20 to determine if it still has the high moly and 200+ VI levels. We should get our answer back in a week or so.
 
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Originally Posted By: rationull
bluesubie: Is the theory that if the break-in oil is indeed different, the engine won't wear in as well with something lower in moly/zinc? Wouldn't 1000 miles be enough? I followed the "don't change the oil until the first scheduled change" recommendation with my last car (07 Civic) and even followed the recommendation and left the factory filter on for 2 OCIs. Car ended up being an oil burner. I'm not blaming that on the OCI but I'm feeling a little more conservative this time.
I'm not sure of the role moly and zinc play for engine break-in. IMO, the style of driving probably plays a bigger factor in regards to oil consumption. I've broken my cars in by the book, which in hindsight was probably a little to easy. -Dennis
 
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Originally Posted By: CATERHAM
Originally Posted By: bluesubie
Several years ago, someone from the SIA plant posted on nasioc that they used regular mineral oil and that moly from uoa's was indeed probably from the assembly lube. SoA has also stated that there was no special break-in oil. But when a fellow BITOG'er emailed ILA recently about the Subaru 0W-20, this was their response:
Quote:
OEMs specify Moly in their factory fill formulations to increase fuel economy during the initial period. In general a factory fill formula will be more robust in the additive treatments etc. This is done for a variety of reasons which I will not go into here. Some of the service fill formulations also contained molybdenum however, with  the transition to the ILSAC GF-5 specification, most 0W-20 service fill 0W-20 formulations now do not have Moly.
-Dennis
Thanks for posting this. That's another reason to stock up on the SM version of the oil while it is still available. Another member has already sent off a VOA sample of the SN GF-5 version of the Toyota 0W-20 to determine if it still has the high moly and 200+ VI levels. We should get our answer back in a week or so.
I believe only the factory fill is robust but the dealer bought SM version is not. Here's a uoa on it. -Dennis
 

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Thanks for that UOA! Surprised to see Mobil 1 recommended in that thread - I usually only hear bad things about Mobil 1 in Subarus, not sure how much truth there is to it though. I suppose I really have three options here: 1) Change the oil out now at 1500 miles w/ the dealer oil. 2) Change the oil out at 2300 miles w/ the dealer oil. 3) Either of the above with something else. If there's a benefit to leaving the factory fill in a bit longer then I can do that. If it would be good to get it out, but this Subaru stuff isn't quite "good enough" yet then I can always buy something else and either use the gold bottles later or mix them in one of our other cars at some point (which are easier on oil). Honestly though there seems to be a lot of uncertainty around with respect to newer 5w-30s in Subaru engines and I'm wondering how much is a real problem and how much is just car people being obsessive. It's all part of the fun but, oh, the uncertainty! wink
 
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Originally Posted By: rationull
................Honestly though there seems to be a lot of uncertainty around with respect to newer 5w-30s in Subaru engines ............
If you subscribe to CATERHAM'S assertion that oil pressure should guide your viscosity choice, then you should be using a 5W-20 or a 0W-20 oil. A synthetic 5W-30 will give you an oil pressure around 85-90 psi at 5000 rpm in a fully warmed up engine, well above Subaru's spec of 43 psi at 5000 rpm at oil temp of 176 degF. I'm not brave enough to try that xW-20 experiment in my turbo Subaru. popcorn
 
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That's why it's easy to run a 20wt oil in a 5W-30 application most of the time, and while many do it without an OP gauge I suggest caution if you don't have one or an oil temp' gauge. The reason is unexpectedly high oil temp's, oil shear and fuel dilution can add up to eliminate your viscosity safety margin. With an OP gauge, assuming you know how to use it, the risk of running an oil too light is virtually zero. With bulk oil temp's of only 176F (80C), a 30wt oil has about the same operational viscosity as a 50wt at 100C. So yes you could easily run a light 20wt oil and as far as your engine would know you'd really still be running a 40wt oil. BTW, Ford spec's a 5W-20 for the 4 cyl turbo in it's line up.
 
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Originally Posted By: CATERHAM
..............BTW, Ford spec's a 5W-20 for the 4 cyl turbo in it's line up.
Subaru does not allow anything lighter than a 5W30 in their 4 cyl turbo motors, even though at 5000 rpm with a warmed up motor the oil pump relief valve gets a vigorous workout. Up until this year, they approved of viscosities up to 20W50, for severe use.
 

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I ended up doing an oil change and dumping this stuff in today. I've never actually poured a synthetic before and it seemed really thin compared even to the 5w-20 conventional I've used, but that could just be my mind playing tricks on my. I probably won't get a UOA for a while, but I may just end up using this stuff at least until I'm out of warranty and willing to buy bulk when oil's on sale. For the price this is just too convenient.
 
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