Amsoil 5W30 Signature Series too thin for Turbo Subaru or 450 hp Ecoboost

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Originally Posted by Jimmy_Russells
Originally Posted by Navi
If there is absolutely zero issues with 5W30 then how come in Europe we see 5W40 and 0W40? If I go on the Mobil 1 website and start plugging in various model names from Audi and MB how come it tells me to use 5W40?
Because Autobahn. Nobody ever seems to talk about this, but nowhere in North America can you maintain 120 mph for two hours, for example. On the Autobahn, save for having to slow to 80 mph sometimes, you can do that no problem. So they have to recommend oils that will not thin out at 240+ degree oil temps.
Exactly. The same reason you see vehicles here that people track bump up to 40 and 50 weights while they're tracking. For example, a 350Z takes what, 5w30? But nobody taking it on the track for the weekend (let me rephrase, nobody knowing what they're doing) is gonna run 5w30 for track time, theyll bump it to a 40 or 50 weight.
 
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30, 40 and nowadays 20 will work if you're spec'd for it. But let's continue with the passive aggressive fear mongering why don't we. (Not specifically aimed at the OP)
 
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WA
In US, you'll never know when the stop & go traffic will clear and you can then speed up to 40 mph. That's why you need a thicker oil just in case!
 
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Thread starter
If I did run Amsoil it would be something thicker like their 0W-40. In studying various UOAs of 0W40 oils there seems to.be a bit more iron wear especially with Mobil 1 0W40 FS. If Amsoil started out thicker like Redline I would be onboard here.
 
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With that engine would it not matter most what the OCI is? Wrong to believe non issue with a 5k OCI but a waste indeed? Longer OCI might not be the best for those chains long term.
 
Originally Posted by Navi
Why are there all these guys out there with modified (Subaru) turbo engines using Shell Rotella T6 5W40?
They're simply trying to compensate for a problem on an engine known to be extremely hard on crank and rod bearings when the boost is turned up. Stock EJ255/257s have no problem going a couple hundred K miles on 5W30; it seems the issue is once these engines go past 400WHP. I'm sure tuning plays a big part as well. It's not a 5W30 problem, it's a "running the engine well outside its designed & intended capabilities" problem.
 
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Originally Posted by Jimmy_Russells
Originally Posted by Navi
If there is absolutely zero issues with 5W30 then how come in Europe we see 5W40 and 0W40? If I go on the Mobil 1 website and start plugging in various model names from Audi and MB how come it tells me to use 5W40?
Because Autobahn. Nobody ever seems to talk about this, but nowhere in North America can you maintain 120 mph for two hours, for example. On the Autobahn, save for having to slow to 80 mph sometimes, you can do that no problem. So they have to recommend oils that will not thin out at 240+ degree oil temps.
Also, In Europe they design and build engines differently than we do here. Engine speeds, ring/liner pressure, ring/big-end clearances , etc. My '87 BMW was an unusual engine built for fuel economy and MANDATED any oil with an HTHS >3.5. If protection is what you are looking for, your looking in the wrong place. Look for an oil with an HTHS >3.5.
 
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Originally Posted by kschachn
Sorry, but this is a thread full of imagined problems and subsequent solutions based on more imagination.
+1
 
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The newer DIT FA engines (100% stock) do seem to be getting along fine, in terms of uoa wear metals, on thinner oils despite the oil usually showing 2-5% fuel dilution and viscosity usually in the mid-20 grade range. The older EJ engines definitely benefit more from thicker oils more than the newer engines IMO. Having said that, Subaru Japan allows Euro 0W-30 and 5W-40 in DIT's so I wouldn't consider running thicker oils in turbo Subaru's as an imagined problem. 2cents https://www.subaru.jp/accessory/engine_oil/lineup/premium02.html
 
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The issue with some of the xw-40 oils is the spread. You ideally want an oil with less VII's in a fuel diluter. More VII's the greater percentage of viscosity loss as fuel dilution increases. A stout 10w30 is a nice choice for an engine that is known for diluting oil. The Delvac 5w40 is likely a solid 40 grade choice.
 
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sonoma
Originally Posted by kschachn
Sorry, but this is a thread full of imagined problems and subsequent solutions based on more imagination.
Dude is asking for help assuming he is developing a strategy for his di engines. The issues with di engines are not imagined, in fact they have been solely responsible for the entire industry moving in the same direction of low CA oils. LSPI does exist, a lubrication strategy can help it. Maybe there are plenty of other factors, but as an owner you can only do so much, why not do what is in your power to do? Amsoil's formula looks like one of the better di friendly formulas out there as far as lspi protection goes, but some di's have been known to shread oil visc, it is another valid concern about starting out thin. There are many things to consider when owning a di turbo, it is advanced ownership, and it seams like even great di formulas can improve upon themselves. Haven't seen a low CA, low noack, high viscosity, high moly oil for this yet, and a lot of the paper out there suggests this would be a good oil formula for di's. let's all just run havo in a box baby and not worry ourselves?
 
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Originally Posted by bluesubie
The newer DIT FA engines (100% stock) do seem to be getting along fine, in terms of uoa wear metals, on thinner oils despite the oil usually showing 2-5% fuel dilution and viscosity usually in the mid-20 grade range. The older EJ engines definitely benefit more from thicker oils more than the newer engines IMO. Having said that, Subaru Japan allows Euro 0W-30 and 5W-40 in DIT's so I wouldn't consider running thicker oils in turbo Subaru's as an imagined problem. 2cents https://www.subaru.jp/accessory/engine_oil/lineup/premium02.html
While I agree they are doing ok on a sheared 20 grade oil, I had better wear metals on a HDEO that stayed in the 30 grade. While ok is good enough for most people, I like the peace of mind of running something thicker and get better wear.
 
Originally Posted by jbutch
While I agree they are doing ok on a sheared 20 grade oil, I had better wear metals on a HDEO that stayed in the 30 grade. While ok is good enough for most people, I like the peace of mind of running something thicker and get better wear.
As dnewton3 has stated, UOAs are not a very good indicator of actual wear. The stuff that shows up in a UOA is only the stuff that is less than ~ 7 microns, which is infinitesimally small. The only real way to measure wear would be a complete teardown and measurements with calipers and micrometers. Your engine could be suffering catastrophic wear and shedding large pieces of metal that would never show up in a UOA. To use a UOA to evaluate oils on a "better/worse" basis is a fool's errand. Long term trending is where UOAs show benefits. If iron is tracking along at 8-15ppm and next UOA jumps to 125 for example, that may be an indicator that something is amiss. But if your UOA goes from 8ppm to 15ppm, that is NOT something to freak out about! Use your UOA to check that the viscosity remained in grade, TBN is greater than 1.0, and iron is less than 150ppm (per Doug Hillary). If any of those fail, you either need to shorten your OCI or choose a more robust oil. Other than that you're imagining perceived benefits from a test that's not designed for or capable of giving you that kind of information.
 
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Originally Posted by SubieRubyRoo
Originally Posted by jbutch
While I agree they are doing ok on a sheared 20 grade oil, I had better wear metals on a HDEO that stayed in the 30 grade. While ok is good enough for most people, I like the peace of mind of running something thicker and get better wear.
As dnewton3 has stated, UOAs are not a very good indicator of actual wear. The stuff that shows up in a UOA is only the stuff that is less than ~ 7 microns, which is infinitesimally small. The only real way to measure wear would be a complete teardown and measurements with calipers and micrometers. Your engine could be suffering catastrophic wear and shedding large pieces of metal that would never show up in a UOA. To use a UOA to evaluate oils on a "better/worse" basis is a fool's errand. Long term trending is where UOAs show benefits. If iron is tracking along at 8-15ppm and next UOA jumps to 125 for example, that may be an indicator that something is amiss. But if your UOA goes from 8ppm to 15ppm, that is NOT something to freak out about! Use your UOA to check that the viscosity remained in grade, TBN is greater than 1.0, and iron is less than 150ppm (per Doug Hillary). If any of those fail, you either need to shorten your OCI or choose a more robust oil. Other than that you're imagining perceived benefits from a test that's not designed for or capable of giving you that kind of information.
You have some good points, but I do feel better with an oil that stays in grade and with lower wear. Might be my ocd smile
 
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I will add that my WRX with most of its 92K on the clock as seen the recommend 5W30. UOAs have came back fine even with the oil sheared to high 20 grade. I have a UOA out to bkackstone currently with a run of Castrol 5W40. I don't expect the numbers to change all that much.
 
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Originally Posted by FA_WRX
I will add that my WRX with most of its 92K on the clock as seen the recommend 5W30. UOAs have came back fine even with the oil sheared to high 20 grade. I have a UOA out to bkackstone currently with a run of Castrol 5W40. I don't expect the numbers to change all that much.
Interested in seeing that uoa. What oil did you put in this time?
 
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Originally Posted by jbutch
Originally Posted by FA_WRX
Interested in seeing that uoa. What oil did you put in this time?
Current run is 5W40 Valvoline MST.
 
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