Another Subaru thread?

gathermewool

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The FA24DIT is a bored-out FA20DIT; I’ve not read and reports of a stroke change.

What none of us know is whether the BEARINGS and other components were changed to accommodate a lower viscosity rating. Does the OP know?

This engine is also in THREE new vehicles, including the Ascent, Legacy XT and Outback XT.

I would only run a more viscous oil based on objective reasoning, such as a TSB, OM addendum, bad UOA, reported failures, etc. I’m not concerned about a loud Subaru boxer sounding a little louder.
 
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Research UOA

So I take it that you have seen repeatable UOA's showing the use of Redline 5w30 in the FA24DIT is in fact, "worse", then the factory pour 0w20?
Also you stated that his Redline 5w30 will most likely sheer down to a 20 grade. So in other words he seemingly will be in spec, in regards to the owners manual, no?

If I was the OP unless I can see the UOA's you want me to research, your original statements would not suffice.

I personally would just keep using the recommended 0w20 unless I noticed oil related issues. But I am also not very familiar with the FA series engines.
 
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So I take it that you have seen repeatable UOA's showing the use of Redline 5w30 in the FA24DIT is in fact, "worse", then the factory pour 0w20?
Also you stated that his Redline 5w30 will most likely sheer down to a 20 grade. So in other words he seemingly will be in spec, in regards to the owners manual, no?

If I was the OP unless I can see the UOA's you want me to research, your original statements would not suffice.

I personally would just keep using the recommended 0w20 unless I noticed oil related issues. But I am also not very familiar with the FA series engines.
I never said the name of oil. Are some better than others yes but generally speaking. You seem to want an argument but not from me. I don't make blank statement like that only inform op that ,0w20 is probably the best oil for his Subaru since he didn't state 5w30 was allowed.
 
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To answer the OP, no I don't follow Subaru's oil change intervals from the manual.
I've owned my BRZ for 7 years. When the car was new I went with the recommended 7000 mile oil changes at first, until I noticed that my car ran rougher, louder. The oil coming out would smell strongly of fuel. Switched to 3000 miles oil changes and think that's more reasonable. As for oil weight, I only run 0w20 in the winter. 0w30 "Euro" in the summer feels about right, because going out on 100* July days running thin oil just didn't feel right, if that makes sense.

Skip that part of the manual to the bottom of the page for the "severe duty" section. That's the one you want.

I would not run 0w40 though. Why would you? Are you tracking the car?
 
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The FA24DIT is a bored-out FA20DIT; I’ve not read and reports of a stroke change.

What none of us know is whether the BEARINGS and other components were changed to accommodate a lower viscosity rating. Does the OP know?

This engine is also in THREE new vehicles, including the Ascent, Legacy XT and Outback XT.

I would only run a more viscous oil based on objective reasoning, such as a TSB, OM addendum, bad UOA, reported failures, etc. I’m not concerned about a loud Subaru boxer sounding a little louder.
All great points. Subaru still does have the same owner's manual language that a thicker viscosity is required in high temps, although they do not define the high temps nor the thicker viscosity. But there's not much uoa data out there on this new engine. You can find maybe 2 or 3 uoa's. Someone on the Outback forum did post a 0W-20 uoa from a new XT that dropped to a 16 grade but I think that's to be expected.

The FA24DIT in the Ascent and new Outback/Legacy is supposed to be a more robust engine than the FA20DIT and Prime Motoring in NJ dropped an Ascent engine into a Crosstrek and is making 500+ whp on the stock block. The FA24 has thicker cylinder walls, more cylinder support molded into the casting, thicker rods, and stronger beehive valve springs (see video below). Can these components alone accommodate a lower grade oil? Not sure if bearing clearances have changed.

Back to the OP's question (or statement?). I don't think I'd be running a high SAPS oil in a Subaru DIT. If I used a high HTHS 5W-30, it would be Rotella T6 5W-30 MV, or an ACEA C3 oil, since those add packs would be a bit friendlier in regards to IVD and possible LSPI. There are lots of uoa's on the FA20DIT on nasioc where Resource Conserving 5W-30 showed low uoa wear metals using an oil with the operating viscosity of a 20 grade due to sheared and/or fuel diluted oil. Yes, there are a few posts about dealer serviced WRX's that had engine failure, but not at the level of the EJ's.

IAG Performance actually recommends reduced SAPS Motul X-clean in their built FA20DIT's. They only recommend Motul X-cess in their built EJ's.

Here's a video with some details of the FA24 where they also mention the Prime Motoring swapped Crosstrek.

Some quotes from Prime Motoring posted on nasioc (I think from PM's social media):

[Subaru] used the FA20 as a building block to learn and grow. Every weak or inefficient point on the FA20 has been improved upon.

The rods are still J shaped but way beefier

From what I can see so far, the future STI will be a great one. I was already a fan of the 2.0 but Subaru really improved on the weak areas. Also using FA24 cylinder heads and modifying them to work in an FA20 application. Only aftermarket part used was a set of ARP studs, everything else was new directly from Subaru. Goal of this is through trial and error, advance the FA platform further and give additional options to future customers. We will take it where no FA24 has been before and probably end up in many little pieces but this is the sacrifice we make for the future of Subaru performance
 
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I have a 2014 model year with the 2.5 (non-turbo) in it. Have always used the 0w20 oil recommended.

Is there a good reason now to change it to 5w30?
 

gathermewool

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All great points. Subaru still does have the same owner's manual language that a thicker viscosity is required in high temps, although they do not define the high temps nor the thicker viscosity. But there's not much uoa data out there on this new engine. You can find maybe 2 or 3 uoa's. Someone on the Outback forum did post a 0W-20 uoa from a new XT that dropped to a 16 grade but I think that's to be expected.

The FA24DIT in the Ascent and new Outback/Legacy is supposed to be a more robust engine than the FA20DIT and Prime Motoring in NJ dropped an Ascent engine into a Crosstrek and is making 500+ whp on the stock block. The FA24 has thicker cylinder walls, more cylinder support molded into the casting, thicker rods, and stronger beehive valve springs (see video below). Can these components alone accommodate a lower grade oil? Not sure if bearing clearances have changed.

Back to the OP's question (or statement?). I don't think I'd be running a high SAPS oil in a Subaru DIT. If I used a high HTHS 5W-30, it would be Rotella T6 5W-30 MV, or an ACEA C3 oil, since those add packs would be a bit friendlier in regards to IVD and possible LSPI. There are lots of uoa's on the FA20DIT on nasioc where Resource Conserving 5W-30 showed low uoa wear metals using an oil with the operating viscosity of a 20 grade due to sheared and/or fuel diluted oil. Yes, there are a few posts about dealer serviced WRX's that had engine failure, but not at the level of the EJ's.

IAG Performance actually recommends reduced SAPS Motul X-clean in their built FA20DIT's. They only recommend Motul X-cess in their built EJ's.

Here's a video with some details of the FA24 where they also mention the Prime Motoring swapped Crosstrek.

Some quotes from Prime Motoring posted on nasioc (I think from PM's social media):

[Subaru] used the FA20 as a building block to learn and grow. Every weak or inefficient point on the FA20 has been improved upon.

The rods are still J shaped but way beefier

From what I can see so far, the future STI will be a great one. I was already a fan of the 2.0 but Subaru really improved on the weak areas. Also using FA24 cylinder heads and modifying them to work in an FA20 application. Only aftermarket part used was a set of ARP studs, everything else was new directly from Subaru. Goal of this is through trial and error, advance the FA platform further and give additional options to future customers. We will take it where no FA24 has been before and probably end up in many little pieces but this is the sacrifice we make for the future of Subaru performance

As usual, an excellent post.
 
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1. Yes, 0W20 helps mpg.
2. No, it's unlikely to be enough to tell in normal use
3. No, we don't know of any negative consequences and if the engineers discovered any they are not talking.
4. The manual gives you "weasel room". If you want to use an ACEA A3 type 5W-30 or 0W-40 do so.
5. A WRX or STI may be speced for higher grade oil because of expected use. I have seen few Forester XT at Open Track events at Road Atlanta.
 

Schwifty

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So I take it that you have seen repeatable UOA's showing the use of Redline 5w30 in the FA24DIT is in fact, "worse", then the factory pour 0w20?
Also you stated that his Redline 5w30 will most likely sheer down to a 20 grade. So in other words he seemingly will be in spec, in regards to the owners manual, no?

If I was the OP unless I can see the UOA's you want me to research, your original statements would not suffice.

I personally would just keep using the recommended 0w20 unless I noticed oil related issues. But I am also not very familiar with the FA series engines.

There will be a UOA on this oil when I pull it around 2500 miles. I'll top it back off with Red Line 0w30 for the winter and most likely will do another after 5k hits. I'm very curious to see how this engine does with shearing down oils. Every other hot turbo 4 cylinder enging I have had, always had some bit of shearing. The EcoBoost series engines have been absolute terrors on many off the shelf oils. Then again these were all Stage 3+ build engines, some with and without turbo swaps. But this Outback XT does and will see some spirited driving throughout the mountain chains with a lot of climbing.

We shall see.
 

Schwifty

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All great points. Subaru still does have the same owner's manual language that a thicker viscosity is required in high temps, although they do not define the high temps nor the thicker viscosity. But there's not much uoa data out there on this new engine. You can find maybe 2 or 3 uoa's. Someone on the Outback forum did post a 0W-20 uoa from a new XT that dropped to a 16 grade but I think that's to be expected.

The FA24DIT in the Ascent and new Outback/Legacy is supposed to be a more robust engine than the FA20DIT and Prime Motoring in NJ dropped an Ascent engine into a Crosstrek and is making 500+ whp on the stock block. The FA24 has thicker cylinder walls, more cylinder support molded into the casting, thicker rods, and stronger beehive valve springs (see video below). Can these components alone accommodate a lower grade oil? Not sure if bearing clearances have changed.

Back to the OP's question (or statement?). I don't think I'd be running a high SAPS oil in a Subaru DIT. If I used a high HTHS 5W-30, it would be Rotella T6 5W-30 MV, or an ACEA C3 oil, since those add packs would be a bit friendlier in regards to IVD and possible LSPI. There are lots of uoa's on the FA20DIT on nasioc where Resource Conserving 5W-30 showed low uoa wear metals using an oil with the operating viscosity of a 20 grade due to sheared and/or fuel diluted oil. Yes, there are a few posts about dealer serviced WRX's that had engine failure, but not at the level of the EJ's.

IAG Performance actually recommends reduced SAPS Motul X-clean in their built FA20DIT's. They only recommend Motul X-cess in their built EJ's.

Here's a video with some details of the FA24 where they also mention the Prime Motoring swapped Crosstrek.

Some quotes from Prime Motoring posted on nasioc (I think from PM's social media):

[Subaru] used the FA20 as a building block to learn and grow. Every weak or inefficient point on the FA20 has been improved upon.

The rods are still J shaped but way beefier

From what I can see so far, the future STI will be a great one. I was already a fan of the 2.0 but Subaru really improved on the weak areas. Also using FA24 cylinder heads and modifying them to work in an FA20 application. Only aftermarket part used was a set of ARP studs, everything else was new directly from Subaru. Goal of this is through trial and error, advance the FA platform further and give additional options to future customers. We will take it where no FA24 has been before and probably end up in many little pieces but this is the sacrifice we make for the future of Subaru performance


It seems like you know exactly what I am inquiring about. However, I do not plan to tune this engine, if anything a very mild tune possibly to resolve some shift point issues and move the hp/torque curve around a bit, but this would be once the vehicle is far further down the line and closer to being or out of warranty. I've always wondered about the Motul line of oils. As for LSPI, I wouldnt be too worried about it in this car to be honest, I can't really see a point where it would be under heavy load at higher RPM ranges where we would most likely see a LSPI event. Also, I would think the other additives in the Red Line would quench it despite the heavy dose of calcium. I'm going to reasearch this Motul line a bit more and look for some UOA's, the only thing I don't like is no moly. In know it's not the end all be all additive, but I do prefer some in there. I'm intrigued.
 
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I'm interested in this discussion as I have a 2016 Outback and a 2018 Traverse. Since the Traverse wants 5w-30 DEXOs oil, I was hoping I could use that in both and not have to buy two types all ths time (6 qts and 5.1 qts). I found the UK owners manual for the 2016 Outback and it calls for 5w-30.
 
Messages
17
Location
Severna Park, MD
I'm interested in this discussion as I have a 2016 Outback and a 2018 Traverse. Since the Traverse wants 5w-30 DEXOs oil, I was hoping I could use that in both and not have to buy two types all ths time (6 qts and 5.1 qts). I found the UK owners manual for the 2016 Outback and it calls for 5w-30.
 
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shanghai
Yep it sure is!

I know, I know, there is a search button, been there done that.
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?
Subaru can use all kinds of engine oils including 0w20 0w30 5w30 0w40 5w40, but 0W20 is recommended for the sake of fuel economy. According to the official website of Japan, 0w30 and 5w40 oils are recommended for users with long traffic jams and a large number of mountain roads and trailers.
 

Schwifty

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Subaru can use all kinds of engine oils including 0w20 0w30 5w30 0w40 5w40, but 0W20 is recommended for the sake of fuel economy. According to the official website of Japan, 0w30 and 5w40 oils are recommended for users with long traffic jams and a large number of mountain roads and trailers.

I've never bothered to read on the Japanese site. I'll have to take a look, but it makes sense, at least for our turbo models to be using a bit more of a robust oil.
 
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shanghai
I've never bothered to read on the Japanese site. I'll have to take a look, but it makes sense, at least for our turbo models to be using a bit more of a robust oil.
Your user manual should have corresponding instructions on the use of engine oil, there will be a recommended viscosity and multiple applicable viscosities.
In fact, most turbine owners in Japan use 5W40 oil
 
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