Another Subaru thread?

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Yep it sure is!

I know, I know, there is a search button, been there done that.

I'll just start by saying I am a bit mystified as of why Subaru has suddenly changed oil types for their 2.4L Turbo engines for the Outbacks and Ascents. So, why the oil weight change for the 2.4L FA24DIT vs the FA20DIT in the older Forester XT? It's literally the same engine platform with a bore/stroke change. So is this just something to meet CAFE regs? At 750 miles I dumped the factory 0w20 oil and filled it with Red Line 5w30 and I have noticed the engine is noticeably quieter and seems overall smoother from it's cold starts, to running at highway speeds, to idling at stoplights. No noticeable loss of MPG or power. It seems like a lot of folks on the Subaru forms are all over the place with what their reasoning's are for this and what oil should really be ran in this engine. To me it just seems that these boxer engines are very "clattery" with 20wt oils.

So, stick with factory recommended oil or break the rules and run what should be ran in it?
 
Yep it sure is!

I know, I know, there is a search button, been there done that.

I'll just start by saying I am a bit mystified as of why Subaru has suddenly changed oil types for their 2.4L Turbo engines for the Outbacks and Ascents. So, why the oil weight change for the 2.4L FA24DIT vs the FA20DIT in the older Forester XT? It's literally the same engine platform with a bore/stroke change. So is this just something to meet CAFE regs? At 750 miles I dumped the factory 0w20 oil and filled it with Red Line 5w30 and I have noticed the engine is noticeably quieter and seems overall smoother from it's cold starts, to running at highway speeds, to idling at stoplights. No noticeable loss of MPG or power. It seems like a lot of folks on the Subaru forms are all over the place with what their reasoning's are for this and what oil should really be ran in this engine. To me it just seems that these boxer engines are very "clattery" with 20wt oils.

So, stick with factory recommended oil or break the rules and run what should be ran in it?

You have not demonstrated what oil should be run it though. It is a different engine too.
 
So is this just something to meet CAFE regs?

Probably. And until this engine gets into other markets, we do not know what the ROW oil requirements will be. Even if I decide to bump up to a higher grade, I'll run an SN/SN+/SP oil though.

By chance do you have an Autumn Green Onyx?
 
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You have not demonstrated what oil should be run it though. It is a different engine too.

5w30 just like the previous generation turbo engine came with that was put in the Forester XT's. The engine is the same, with nothing more than a change to the bore and stroke to make it a 2.4L for the Ascents and Outbacks. Why would Subaru engineers increase the engines bore and stroke, its total HP/Tq numbers and put it in two vehicles which are heavier than the Forester, and have tow ratings higher than the forester and drop the oil weight? Seems silly right?
 
Probably. And until this engine gets into other markets, we do not know what the ROW oil requirements will be. Even if I decide to bump up to a higher grade, I'll run an SN/SN+/SP oil though.

By chance do you have an Autumn Green Onyx?

I don't. The Onxy edition ones are a bit slim around here.
 
I didn’t mention the brand. Your engine calls for 0w20 but you used 5w30 then asked what we thought? The deed is done.

You sound familiar.

You are missing the whole point. Did you read anything I wrote about the engine being literally the same other than a change of bore/stroke? And no, I'm not familiar to you, I am new here.
 
So, stick with factory recommended oil or break the rules and run what should be ran in it?

I'm a bit confused. How can "what should be ran it it" be different from the factory recommended oil?

How can one be breaking the rules if running "what should be ran in it"? Shouldn't that be what the owners manual says?

I've been a member here since 2003 and this is one of the most confusing postings that l have encountered in 17 years of being here. Maybe my reading comprehension is deteriorating as l get up there in age.
 
I'm a bit confused. How can "what should be ran it it" be different from the factory recommended oil?

How can one be breaking the rules if running "what should be ran in it"? Shouldn't that be what the owners manual says?

I've been a member here since 2003 and this is one of the most confusing postings that l have encountered in 17 years of being here. Maybe my reading comprehension is deteriorating as l get up there in age.

Ahhh you are one of those "follow the manual guys". See the previous platform and engine this was build off of ran with 5w30, but suddenly a change of bore/stroke and tossing it into two new cars they changed it to 0w20 with no reasoning other that to meet CAFE standards/emissions baloney. My question is, why? Why would Subaru downgrade the oil after increasing the power and tossing it into heavier vehicles?
 
Ahhh you are one of those "follow the manual guys". See the previous platform and engine this was build off of ran with 5w30, but suddenly a change of bore/stroke and tossing it into two new cars they changed it to 0w20 with no reasoning other that to meet CAFE standards/emissions baloney. My question is, why? Why would Subaru downgrade the oil after increasing the power and tossing it into heavier vehicles?

Thanks for the clarification.

I really don't have an answer to your question as my level of oil knowledge is not commensurate with the level required to override the Subaru engineers recommendations. I don't have the finances to independently validate running 5w30 in a turbocharged boxer engine so my opinion, even if l had one, would be useless.

It would be foolish on my part to agree with your decision or tell you you're a lubrication genius for eschewing the recommendation of the owners manual because your question is far beyond the scope of my lubrication qualifications.
 
I'll just start by saying I am a bit mystified as of why Subaru has suddenly changed oil types for their 2.4L Turbo engines for the Outbacks and Ascents. So, why the oil weight change for the 2.4L FA24DIT vs the FA20DIT in the older Forester XT? It's literally the same engine platform with a bore/stroke change. So is this just something to meet CAFE regs? At 750 miles I dumped the factory 0w20 oil and filled it with Red Line 5w30 and I have noticed the engine is noticeably quieter and seems overall smoother from it's cold starts, to running at highway speeds, to idling at stoplights. No noticeable loss of MPG or power. It seems like a lot of folks on the Subaru forms are all over the place with what their reasoning's are for this and what oil should really be ran in this engine. To me it just seems that these boxer engines are very "clattery" with 20wt oils
First off not the same once you change bore and stroke. Second you dumped perfectly fine oil at 750 miles
You then change the grade of oil to a worse base since you went to 5w30. 5w30 seems to shear to a 20 grade oil over time so accomplished nothing but made you feel better
Finally engine isn't broke in so you can't make an accurate fuel mileage comparison. Noise is subjective and again it isn't broke in. You could run 0 or 5w20 for couple of hundred thousand miles without oil failure. After all 5w30 is really close to 20 grade oil and probably won't hurt anything but I will not say that as I haven't seen manual.
 
First off not the same once you change bore and stroke. Second you dumped perfectly fine oil at 750 miles
You then change the grade of oil to a worse base since you went to 5w30. 5w30 seems to shear to a 20 grade oil over time so accomplished nothing but made you feel better
Finally engine isn't broke in so you can't make an accurate fuel mileage comparison. Noise is subjective and again it isn't broke in. You could run 0 or 5w20 for couple of hundred thousand miles without oil failure. After all 5w30 is really close to 20 grade oil and probably won't hurt anything but I will not say that as I haven't seen manual.

I believe this assumption, is as solid as the OP's assumption, as to why he chose to go with a 5w30.. Unless you could elaborate a bit more, instead of stating it as a fact.
 
"...they changed it to 0w20 with no reasoning other that to meet CAFE standards/emissions baloney. My question is, why? Why would Subaru downgrade the oil after increasing the power and tossing it into heavier vehicles?"

I think you're mind is made up to run what you'd like. Nothing wrong with that. I'm of the belief that so much emphasis has been placed on lower viscosity oils that efforts to bring the wear protection up to the level of more viscous HTHS oils has been a serious focus of the oil manufacturers - albeit through additive technology.
 
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