2017 Subaru 2.5L Interval Question

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Car is usually driven 55-65mph to commute. No major hills, wind, etc. I'd consider it a super easy on oil commute. And often push past the 6k change interval.

Recently road tripped about 2k miles each way. Uphill, downhill, mountains, into strong Midwest winds, all with cruise set at 80+mph at times. Is this severe? I added 2 quarts of oil, I'm assuming due to the engine load and higher than typical rpms (4k+ uphill).

Would you change at 6k or let it go until 7-7.5k?

Looking forward to contradicting views already!
 

SR5

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Not severe.

The oil got up to temp and stayed there, which is good. You topped it up when required, which is good.
To me cold climate with short trips and the oil not getting up to temp is severe.
 
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Well I'd just do a UOA and see what kind of a baseline that oil really had in your car at this mileage. Then next time you'll know. But another 1500 miles just how many tenths of a cents a mile or less are you going to save in 1500 miles?
 
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I dont like extended drains in a horizontal engine.

The subaru 6000mile interval is for a reason. If they could extend out to 10k like most others I'm sure they would.

just my 2 cents.. my 22 forester will be getting 5k mile OCI but it also has GDI.
 
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It is probably the start of oil consumption, which is unfortunately quite common on the FB25 engines. There isn't much that can be done about it aside from a new short block. I suppose you can try an oil with better cleaning properties (e.g. Redline or HPL) in hopes of cleaning the piston ring deposits, but usually once it starts, it only goes downhill.
 
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It is probably the start of oil consumption, which is unfortunately quite common on the FB25 engines. There isn't much that can be done about it aside from a new short block. I suppose you can try an oil with better cleaning properties (e.g. Redline or HPL) in hopes of cleaning the piston ring deposits, but usually once it starts, it only goes downhill.
I had 3 fb25.. besides the outback that burned oil from day 1 through a rering job and a short block.. still used oil.
the 2 foresters used a minimal amount maybe .5qt over 5000 miles. IIRC.
being MT they did use abit more oil in the mountains and on extended high speed trips.
 
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I had 3 fb25.. besides the outback that burned oil from day 1 through a rering job and a short block.. still used oil.
the 2 foresters used a minimal amount maybe .5qt over 5000 miles. IIRC.
being MT they did use abit more oil in the mountains and on extended high speed trips.
Next door neighbor has a 14, it goes thru 1 qt every 2500-3K. Recently checked it after 3K on Havoline Lifelong 5W30 and the stick was dry. I added 1 qt of HPL Engine Cleaner to top-off, will recheck in 3k and see. Might even do a run of HPL's oil in it.
 
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Car is usually driven 55-65mph to commute. No major hills, wind, etc. I'd consider it a super easy on oil commute. And often push past the 6k change interval.

Recently road tripped about 2k miles each way. Uphill, downhill, mountains, into strong Midwest winds, all with cruise set at 80+mph at times. Is this severe? I added 2 quarts of oil, I'm assuming due to the engine load and higher than typical rpms (4k+ uphill).

Would you change at 6k or let it go until 7-7.5k?

Looking forward to contradicting views already!

My question is what would be motivating you to go beyond the 6000 mile recommend oil change interval?

FWIW Subaru originally had the standard OCI recommendation for this engine at 7500 miles until widespread reports of oil consumption began occurring which compelled them to shorten the standard recommend OCI to 6000 miles.
 
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My question is what would be motivating you to go beyond the 6000 mile recommend oil change interval?
Because theoretically, it is a small engine with a somewhat large sump, port-injected and no special needs. So 6K on 0W-20 seems conservative.
 
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I have a 2018 Subaru Forester. Changed oil out at 2200 miles after buying it new. Couple oil changes at 6000 mile per Subaru. Sent a sample to Blackstone. They said try 8000 miles next time. I did and it came back good, so they said try 10,000 miles next change.

Then I retired and don't drive many miles. Engine burns no oil, but I'm backing it down to 5000 mile changes, due to short trips.
 

Rex

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I have a 2017 Subaru Crosstrek running the 2.0L 4-cyl engine. Currently running Premium Plus HPL 0W20 oil in the engine with 8,180 miles on the oil. No consumption used. At 15K will sample the oil, change filter, and top off and continue running. The Subie seems to like HPL..
 
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I have a 2017 Subaru Crosstrek running the 2.0L 4-cyl engine. Currently running Premium Plus HPL 0W20 oil in the engine with 8,180 miles on the oil. No consumption used. At 15K will sample the oil, change filter, and top off and continue running. The Subie seems to like HPL..
At 15k I hope you have an engine to tell us about.
 

HowAboutThis

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My question is what would be motivating you to go beyond the 6000 mile recommend oil change interval?

FWIW Subaru originally had the standard OCI recommendation for this engine at 7500 miles until widespread reports of oil consumption began occurring which compelled them to shorten the standard recommend OCI to 6000 miles.
If it's consuming, and you're topping off, isn't your oil newer by the top off oil to sump size ratio? Would seem if they use oil, and you need to add, you could go longer per change, because you're adding new oil. For instance, right now, about 40% of my oil (2qts) has been replaced with "top off" fresh oil. So the oil in my sump doesn't really have 6k on it right now. About 60% of it has 6k and 20% has 1,700 and 20% has 500.

Doesn't make sense why they'd shorten the interval because you're adding fresh oil. There has to be another reason they shortened it, or they just assume people will let them go dry and kill engines so 6k make sure they'd get it changed before empty. Which is a rule for average people but isn't logical if you check fluids.
 

HowAboutThis

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It is probably the start of oil consumption, which is unfortunately quite common on the FB25 engines. There isn't much that can be done about it aside from a new short block. I suppose you can try an oil with better cleaning properties (e.g. Redline or HPL) in hopes of cleaning the piston ring deposits, but usually once it starts, it only goes downhill.
It uses very little in 6k under our typical driving. Maybe 1/2qt. During any road trip with mountains, wind, high rpms (4k+), and higher speed (80mph) it uses about a quart per thousand. It's been this way since a lot of miles ago. Hoping it's not a sign of things to come. Through the Midwest at 80 for 3 hour blocks into strong headwinds where it ran between 3500-4500rpms at all times was when most of the loss occurred.
 
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If it's consuming, and you're topping off, isn't your oil newer by the top off oil to sump size ratio? Would seem if they use oil, and you need to add, you could go longer per change, because you're adding new oil. For instance, right now, about 40% of my oil (2qts) has been replaced with "top off" fresh oil. So the oil in my sump doesn't really have 6k on it right now. About 60% of it has 6k and 20% has 1,700 and 20% has 500.

Doesn't make sense why they'd shorten the interval because you're adding fresh oil. There has to be another reason they shortened it, or they just assume people will let them go dry and kill engines so 6k make sure they'd get it changed before empty. Which is a rule for average people but isn't logical if you check fluids.

Well how about this, perhaps one should NEVER drain the oil and just keep adding? Why not? It couldn't possibly be problematic, right???
 

HowAboutThis

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Well how about this, perhaps one should NEVER drain the oil and just keep adding? Why not? It couldn't possibly be problematic, right???
Under the right (wrong?) conditions I think your sarcasm and hyperbole might be less destructive to an engine than your sarcasm and hyperbole are implying. Since we're trying to be clever, I guess, let's take your extreme example to the extreme. What if a car never burned oil except random times every 5k miles it burned 5qts in a 10 mile period. How's that different than a 5qt drain and fill normal oil change? After that random massive oil burning and top off in a 10 mile stretch in this bizarre car, you're implying you'd go dump the 5qts you just added that has at most 10 miles on it and replace with 5 quarts of fresh oil.
 
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It uses very little in 6k under our typical driving. Maybe 1/2qt. During any road trip with mountains, wind, high rpms (4k+), and higher speed (80mph) it uses about a quart per thousand. It's been this way since a lot of miles ago. Hoping it's not a sign of things to come. Through the Midwest at 80 for 3 hour blocks into strong headwinds where it ran between 3500-4500rpms at all times was when most of the loss occurred.
I’ve had similar results, albeit with different engines, when driving high rpm highway/mountains/summer temps. Used more oil than normal. Everyone loves highway driving - I do too - and it’s easier on oil, but I think it can also be higher on consumption when at consistent high speeds. IMO.

Personally I don’t anything is going to happen if you extend it to 7,500 as long as the oil is topped up, BUT I would consistently keep myself on a 6,000 interval with your engine (based on direct injection, what I’ve read about oil consumption in subarus, etc).
 
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