HPL in FB25 Outback, cleaning/consumption?

No, plan is to try 5W30 and do more data gathering before considering something besides HPL
If you switch back to the other oils that showed much lower oil consumption and it goes back down that will tell you something. Likewise, if you switch back and the oil consumption is still high, or higher then that will also tell you something. You can't find a cause without doing some testing like that.
 
Tough call for those of us who intentionally own cars in model years that don’t have DI, electric power steering, and camera/cruise control nannies - can you even buy something like this new?
I’m in your same boat. It was only due to a smoking deal on my F150 that I begrudgingly bought a 3.5EB. As you can see by my mother vehicles (‘18 Forester, 07 Impreza) I like simple, similar, easy to fix engines.

The more I learn about oils, the more I think people who have used the Mobil oils with AN/Esters are much better off, and that, barring a special case like my 07 Impreza with original HGs, anyone who can afford oils with AN/Esters will have a longer, healthier engine life no matter when they switch to these oils.
 
If you switch back to the other oils that showed much lower oil consumption and it goes back down that will tell you something. Likewise, if you switch back and the oil consumption is still high, or higher then that will also tell you something. You can't find a cause without doing some testing like that.
That’s a good option and I have considered it, it’s not the first thing I’m going to try.
 
Tough call for those of us who intentionally own cars in model years that don’t have DI, electric power steering, and camera/cruise control nannies - can you even buy something like this new?
Fortunately you can still get a Jeep with a 3.6L Pentaster w/o DI. It will have stop/start, electric PS, and the other nanny items though.
 
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That’s a good option and I have considered it, it’s not the first thing I’m going to try.
If I was concerned about why the oil consumption started with the different oil, I'd go back to one of the oils that didn't show much consumption. I'd try the thicker HPL after that ... but that's just the testing logic I'd go with to get the answer sooner than later.
 
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I’m in your same boat. It was only due to a smoking deal on my F150 that I begrudgingly bought a 3.5EB. As you can see by my mother vehicles (‘18 Forester, 07 Impreza) I like simple, similar, easy to fix engines.

The more I learn about oils, the more I think people who have used the Mobil oils with AN/Esters are much better off, and that, barring a special case like my 07 Impreza with original HGs, anyone who can afford oils with AN/Esters will have a longer, healthier engine life no matter when they switch to these oils.
I managed to get several Hondas to around 300K with minimal intention about full maintenance, just decent Walmart aisle synthetic oil changes.
Now that it seems that my next car purchase may be forced to be electric/hybrid/overly complicated and expensive in my humble opinion, I want to get both my Subies fully properly maintained and keep them there, figure out rustproofing to slow down the Midwest salt, then pray and cross my fingers that none of the local wildlife decides to total them out for me before I’m good and tired of them.

Plenty of BMWs are “fine” and in spec consuming oil at my worst observed rate so far. So long as I don’t end up finding massive RTV leaks putting the oil back on my driveway, I still think HPL or other ester and high quality base oil is the way to go in all of my cars.
 
If I was concerned about why the oil consumption started with the different oil, I go back to one of the oils that didn't show much consumption. I'd try the thicker HPL after that ... but that's just the testing logic I'd go with to get the answer sooner than later.
Dumping 4.8 quarts of 3 week old HPL then going back to the Walmart oil aisle breaks my heart
 
Just cut the filter, see if it's got stuff in it. Then top off what you lost. Saves having to dump the oil and at least then you'd know if any cleaning is happening.
Getting my filter cutter back from the friend I lent it to tomorrow, and have an Amsoil filter coming tomorrow too. Will have it cut open Thursday at this rate
 
Dumping 4.8 quarts of 3 week old HPL then going back to the Walmart oil aisle breaks my heart
You going to dump the 3 week old HPL 5W-20 to put in HPL 5W-30? How long are you planning on running the 5W-20, and what are you using to top off the consumption?
 
You going to dump the 3 week old HPL 5W-20 to put in HPL 5W-30? How long are you planning on running the 5W-20, and what are you using to top off the consumption?
If this is the case, I’d leave the 5w20 in, let it be consumed, and do the top-offs with the 5w30. You’re refreshing additives, so I would continue to change the filter at 5k intervals, and run this oil til the 5 quarts of 5w30 has been consumed, and the oil is down to the full mark on the stick.
 
If this is the case, I’d leave the 5w20 in, let it be consumed, and do the top-offs with the 5w30. You’re refreshing additives, so I would continue to change the filter at 5k intervals, and run this oil til the 5 quarts of 5w30 has been consumed, and the oil is down to the full mark on the stick.
IMO, that doesn't give a very direct answer if it's the oil or if something that has changed in the engine from possible cleaning. Switching back to the old oil will give a much more definitive answer.

Heck, drain the 3 week old HPL out into a very clean container and save it for later is another option.
 
If this is the case, I’d leave the 5w20 in, let it be consumed, and do the top-offs with the 5w30. You’re refreshing additives, so I would continue to change the filter at 5k intervals, and run this oil til the 5 quarts of 5w30 has been consumed, and the oil is down to the full mark on the stick.
That is the plan Dave hatched when we talked, I imagine by the time another few thousand miles have passed with religious checking of levels and by then it’ll be more 5W30 than 5W20 (if it keeps disappearing) and I’ll have much more of a leg to stand on regarding staying with HPL or trying to go back to Castrol.
 
That is the plan Dave hatched when we talked, I imagine by the time another few thousand miles have passed with religious checking of levels and by then it’ll be more 5W30 than 5W20 (if it keeps disappearing) and I’ll have much more of a leg to stand on regarding staying with HPL or trying to go back to Castrol.
I know it’s cheesy, but I think it’s pretty cool that I came up with the same idea as somebody as smart as Dave 🤣

It’s the little things in life that matter 😎
 
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Tough call for those of us who intentionally own cars in model years that don’t have DI, electric power steering, and camera/cruise control nannies - can you even buy something like this new?
Same boat. I ordered my 18 forester port injected fb25 manual transmission with the intent of the breaking it in myself and owning the entire life of the vehicle. Having the cleanest piston rings broken in correctly is imperative and for that reason trying HPL was a no brainer. I recommend continuing the HPL the entire length of the interval you were planning and see what happens to consumption. To entertain the idea of perhaps my engines believed pcv related consumption wasnt from the pcv valve, it consumed no oil until 1,000 miles into the interval, then 3/4 of a quart in 700 mile highway trip. And then replacing the pcv valve no consumption for thousands of miles after including all day highway same conditions. If this was true of my engine and a normal symptom of the rings being cleaned in FB25 then perhaps your increased consumption is a brief period. Just a thought.
 
To entertain the idea of perhaps my engines believed pcv related consumption wasnt from the pcv valve, it consumed no oil until 1,000 miles into the interval, then 3/4 of a quart in 700 mile highway trip. And then replacing the pcv valve no consumption for thousands of miles after including all day highway same conditions. If this was true of my engine and a normal symptom of the rings being cleaned in FB25 then perhaps your increased consumption is a brief period. Just a thought.
I’ve thought of that too, I am really hoping that I find the same situation and my concern is all for nothing. With that said I had never heard of consumption accelerating then decelerating with no mechanical changes ever with any car in the 20+ years I’ve been doing this, nor can I think up any mechanism of action that would make it happen. I appreciate the news!

Stick Subarus for life haha!
 
heavier oils can help up to a point, BUT when the girlfriends 13 2.5 malibu start using a qt in 700 she dumped it + luckily got a good year old 18 optima that uses NO oil using 10-30 quaker state full fake synthetic!! my port injected hopped up 2001 jetta 1.8T was at 1500 to a quart depending on how many times i boosted to 25 lb, not bad for 200 thou IMO + NO rust either. prolly the best car i ever owned + 30 mpgs as well after ENHANCEMENTS !!! 38 BEFORE!!
 
Thoughts? Is there some way that “cleaning” temporarily changes oil consumption in a way like this? Since I’m out of top off bottles of HPL and need to order more since I’ve used the whole 6 quart box, should I still buy 5W20 or go to a 30? Was this whole thing a bad idea?

How did I turn a non-consuming FB25 into a guzzler? Will it stop?

What am I missing?

(I am reaching out to David already)
I noticed some increase in leaks with the HPL EC30 after about 1k miles at the valve covers that subsided when I changed the oil out at the 5k oci. Although yours is a different usage at the rings, I do think I would ride it out for a bit and top off w a heavier HPL oil to see if it helps long term. Next order I would get a Xw30. It may have cleaned some and made a way for it to leak but continue to clean and resolve if/when fully cleaned.
 
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