Quality oil for Subaru Ascent FA2.4F

I think if you're really worried about DI turbo issues, use RLI Bio-Plus in the fuel (1oz / 15gal - so a gallon lasts many miles) and maybe also LC20 in the oil.
That's been my regimen with my VW. No issues. Settled on this path after researching the old VW/Audi carbon buildup issues. Terry Dyson worked with owners and they found RLI oil and fuel additive to be the best treatment. I figured LC20 would be a good additive instead of RLI oil. (I run M1 as the cheapest VW502 sale/rebate price - much lower than RLI oil + LC20)
 
I think if you're really worried about DI turbo issues, use RLI Bio-Plus in the fuel (1oz / 15gal - so a gallon lasts many miles) and maybe also LC20 in the oil.
That's been my regimen with my VW. No issues. Settled on this path after researching the old VW/Audi carbon buildup issues. Terry Dyson worked with owners and they found RLI oil and fuel additive to be the best treatment. I figured LC20 would be a good additive instead of RLI oil. (I run M1 as the cheapest VW502 sale/rebate price - much lower than RLI oil + LC20)
How exactly a gas additive is gonna help with DI turbo issues?
 
Castrol Edge Extended Performance 0w20 (Gold Bottle)

API SP rated and is has the Mercedes Benz 229.71 approval, good luck finding a 0w20 with a high level European approval like that for less.
 
So you have no data but others’ opinions on forums I see. BTW it’d be helpful if you could at least shape your point on what exactly you’re talking about instead of throwing random links at me
Were you expecting a white paper?
I'm more trusting of people's opinions of RLI as they worked with Terry Dyson through the issue. Much better "data" than "hey guys, put some TCW3 in your gas tank". 99.9% of forums are opinions. As I said, I make your own conclusion.
I only own one turbo DI engine, and run RLI and LC20. I don't have any issues, but I don't have a second vehicle with the same engine and no additives for a control. Sorry to not provide the evidence you desire. Not my job.
 
Read the owners manual. If 0w20 isn't available, use a 5w30 blah blah but switch back to 0w20.... conventional can be used if synthetic isn't available blah blah blah....some of the same silly CAFE wording that Toyota uses...
I don't care for Pimtac opinion on timing chains. And, the VVT system isn't going to care if you step up 1 grade from the 0w20, as allowed in the manual. Subaru, like Toyota, doesn't purposely program failure because of oil viscosity unlike a couple domestic manufacturers.
So, I would just use a synthetic 5w30 year round permanently.

It is not my opinion. There are numerous threads here that explain how the newer SP/GF6 oils improve on the timing chain issue. That was one of the main goals of the new rating.
 
Wow, been some time before someone mentioned LC20, RLI, BIO-PLUS....
RLI... is it the best? don't know. Its a good oil but don't go out of my way for it or other hen's teeth.
Fuel additives... sure, maybe hit the injectors with a bottle of PEA in the tank. Will also address CC and piston top buildup. Sticking with top tier fuel is a good start. IVD deposits.... wonder how Subaru addresses it.... I address it with a yearly IVD spray cleaning.

Aren't the 5w30's also SP/GF6 too? Doesn't that mean it'll protect the timing chains? API ... about 50 years late with timing chain protection. Thanking API(or just Ford) for the late effort. Have replaced plenty over the years and tend to learn what owners are doing for grades/maintenance/intervals.... I didn't need SP/GF6.
And, were some oils ahead of API by protecting the chains long ago? Yes, they were!

I get a kick out of TerryDyson's opinions too. But, I don't see his opinion as usable valid testing, like the UOA's here.
 
Were you expecting a white paper?
I'm more trusting of people's opinions of RLI as they worked with Terry Dyson through the issue. Much better "data" than "hey guys, put some TCW3 in your gas tank". 99.9% of forums are opinions. As I said, I make your own conclusion.
I only own one turbo DI engine, and run RLI and LC20. I don't have any issues, but I don't have a second vehicle with the same engine and no additives for a control. Sorry to not provide the evidence you desire. Not my job.
Oh wow, Terry Dyson! Am I supposed to know who that is?
I put it on google and
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My point was - can you please explain what is the problem you're solving? No need to be aggressive here
 
I think if you're really worried about DI turbo issues, use RLI Bio-Plus in the fuel (1oz / 15gal - so a gallon lasts many miles) and maybe also LC20 in the oil.
That's been my regimen with my VW. No issues. Settled on this path after researching the old VW/Audi carbon buildup issues. Terry Dyson worked with owners and they found RLI oil and fuel additive to be the best treatment. I figured LC20 would be a good additive instead of RLI oil. (I run M1 as the cheapest VW502 sale/rebate price - much lower than RLI oil + LC20)
I’ll have to check that out. Thank you very much!!
 
I’ll have to check that out. Thank you very much!!
The solutions to the design problems of the VW group DI engines are not applicable to other manufacturers. AFAIK no fuel additive can help with the carbon buildup since the injector is not spraying the fuel over the valves. Welcome to change my mind :)
 
Aren't the 5w30's also SP/GF6 too? Doesn't that mean it'll protect the timing chains? API ... about 50 years late with timing chain protection. Thanking API(or just Ford) for the late effort. Have replaced plenty over the years and tend to learn what owners are doing for


Sure. Any grade of SP/GF6 has the same goals.

The timing chains today are much different than the wide timing chains of 50 years ago. Some engines have long convoluted chains too compared with the shorter designs of yesteryear.

Run what the owners manual recommends and have no worries.
 
Boy, I didn’t think we would get heated over some of the topics in here. Haha Just playing.

Something I have noticed in the past working on GM’a 3.6 in the Acadia/Traverse/etc and Ford 5.4’s is that some timing chain guides and phasers break down far sooner than others. Obviously OCI’s and driving habits effect that, but I believe oil affects that more so. I’ve seen some GM 3.6’s fail in 80K with insane amounts of carbon and regular OCI’s. While others make it 150k+. Same with the Ford 5.4.

I’ve read the owners manual and remember seeing that 5w30 conventional can be used if there are no other options. But I won’t be in a situation where that is required. I believe a 0w30 or even 0w40 would be fine in the summer, but I doubt I would see any advantages in doing so. I tend to drive a little more aggressive than my wife, but at no point am doing track days with a large SUV or extended periods of full throttle.
 
The solutions to the design problems of the VW group DI engines are not applicable to other manufacturers. AFAIK no fuel additive can help with the carbon buildup since the injector is not spraying the fuel over the valves. Welcome to change my mind :)
If it helped VWs why wouldn't it help other GDI engines? Change my mind ;)

My turbo GDI is not the same engine that exhibited issues of build-up, but I figured a little preventative additives sure wouldn't hurt. I chose LC20 as it was mentioned to "liquify carbon" (BITOG days of yore) - along with the Bio-Plus, perhaps any ring blow-by might clean something? Who the F knows for sure, but with my generation of VW engines, a few have done carbon cleaning. It is not common, but not zero, either. I've had absolutely zero drivability issues over 70k miles and have averaged higher than the EPA hwy mpg rating.
Maybe I'm doing something for nothing, maybe there would be zero issues without my regimen, maybe there would be. I have no idea. For $60 over the ownership of my vehicle, though, seems worth it. Never using Techron/PEA b/c I assume I've prevented build-up/clean injectors.

If I ever need a carbon cleaning, I'd be sure to post pictures. Doubt that day will come though.
 
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Now that we’ve somewhat beaten the oil question like a dead horse.

What do you guys think about adding a catch can at some point? I’ve never really needed one before but I have seen some evidence of it helping on turbo engines and keeping things cleaner.
 
If it helped VWs why wouldn't it help other GDI engines? Change my mind ;)
Prove of before and after, then I'll gladly change my mind and agree with your point.
If your engine is a DI one, there's absolutely no way a fuel additive can fight the valve carbon build-up

Upd. this is for diesel engines, but the idea is the same with gas engines - the injectors just don't spray over the valves. So unless you know magic or have some other ways of delivering your additive to the valves I dont see how it helped you
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Now that we’ve somewhat beaten the oil question like a dead horse.

What do you guys think about adding a catch can at some point? I’ve never really needed one before but I have seen some evidence of it helping on turbo engines and keeping things cleaner.
You are better off starting a new thread in a different forum when it is a different subject. Not just doing an "add-on".

There have been other members that do this quite a bit.
 
Now that we’ve somewhat beaten the oil question like a dead horse.

What do you guys think about adding a catch can at some point? I’ve never really needed one before but I have seen some evidence of it helping on turbo engines and keeping things cleaner.
I've been thinking about it too. Ended up just using the oil with smaller Noack figures
 
I've been thinking about it too. Ended up just using the oil with smaller Noack figures
I need before and after.
:D
Now that we’ve somewhat beaten the oil question like a dead horse.

What do you guys think about adding a catch can at some point? I’ve never really needed one before but I have seen some evidence of it helping on turbo engines and keeping things cleaner.
I went the additive route, after reading of others using catch cans and not really knowing what difference, if any, they made. Plenty of owners will do zero and not have an issue, also. But we can't spell BITOG without OCD.
 
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