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2018 Outback 2.5i Touring
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I've had my first OB since 11/2017 and right now I have about 4K miles. It's been 6 months and dealer sent me an email reminder that I'm due for an oil change. In the past I've always done them at 6000 mile intervals regardless of months. Opinions?
 

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1999 30th Anniversary Legacy Outback DOHC 2.5L 4EAT, 2008 Impreza WRX 2.5L 5MT, 2008 Impreza Wagon 2.5L 4EAT
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I usually do 6 months or 5k miles but those are on older vehicles (99/03/04). For the full synthetic 6k miles seems ok. Just make sure you check the oil from time to time (assuming they still left the dipstick on the 2018s)
 

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6000 miles, 6 months, whichever comes first if you want to keep your warranty in play.
 

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OBW H6 VDC, Tribeca, XT6
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This:
6000 miles, 6 months, whichever comes first if you want to keep your warranty in play.
That

It's pointless to risk warranty/relationship on a 5 digit car for a 2 digit expense and something as innocuous as an oil change.

That said - you are correct, the time constraint for oil is practically/mechanically pointless - but you need to follow the owners manual for warranty purposes. so after the warranty expires then you can deviate.

the chances of you needing to worry about warranty/oil/them checking/or caring are about 0.00000000000005%, so we're sort of talking about nothing and you'll never recall this thread again after you decide whatever you want to decide.
 

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6 months is fine after warranty is up your call. My 2seater get changed every 12 months. Same with my truck both run between 2500-4000miles a yr.
 

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2007 2.5 L Obsidian Black Outback XTL
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Some of it depends upon what kind of miles and your local environment. If it is all short distance stop and go stuff then the oil really does not get a chance to heat up and drive off moisture that condenses inside of the crankcase when the engine cools down in a very damp or humid environment.

As an engine heats up the air space in the crankcase expands and naturally gets pushed out through the PCV valve and back in to the intake manifold. When you stop driving and the car cools down the airspace sucks air inwards from the outside environment. It is only a little bit of moisture each time, maybe less than a cc each driving cycle, but if the engine never properly gets hot that moisture just builds up. Day after day more cc's of water accumulate in the crankcase. After six months of that kind of driving you can see where you may only have 2000 miles on the car but maybe enough water to form a tasty sludge or some corrosion.

I have seen the diurnal cycle of heating-cooling, expansion-contraction, breathe in- breathe out leaving behind measurable amounts of water in sleeve bearing housings on large industrial pumps. A car engine is not that different.
 

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2017 2.5i Premium Lapis Blue
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The service schedule from my dealer is 6 months/5,000 miles, fewer miles than the standard Subaru schedule. I'm okay with it since I am likely going to hit both of those about the same time anyway. I'm just going to try to time it out so there isn't an oil change due right before my lease is up. Might as well try to save the $66 if I can. :nerd:
 

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'15 Outback 2.5i Premium
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Some of it depends upon what kind of miles and your local environment. If it is all short distance stop and go stuff then the oil really does not get a chance to heat up and drive off moisture that condenses inside of the crankcase when the engine cools down in a very damp or humid environment.

As an engine heats up the air space in the crankcase expands and naturally gets pushed out through the PCV valve and back in to the intake manifold. When you stop driving and the car cools down the airspace sucks air inwards from the outside environment. It is only a little bit of moisture each time, maybe less than a cc each driving cycle, but if the engine never properly gets hot that moisture just builds up. Day after day more cc's of water accumulate in the crankcase. After six months of that kind of driving you can see where you may only have 2000 miles on the car but maybe enough water to form a tasty sludge or some corrosion.

I have seen the diurnal cycle of heating-cooling, expansion-contraction, breathe in- breathe out leaving behind measurable amounts of water in sleeve bearing housings on large industrial pumps. A car engine is not that different.
Water is a combustion product from burning hydrocarbons. I suspect that's a bigger source for water vapor in the crankcase than atmospheric water.
 

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2013 Outback 2.5i Convenience
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Water is a combustion product from burning hydrocarbons. I suspect that's a bigger source for water vapor in the crankcase than atmospheric water.
Yes and this is what likely meant by the "short trip not getting the engine to temp" comment. Also at play is where OP is from. It's cold in Wisconsin in winter, short trips there would be that much worse in winter.


I recall Ford fusion hybrids were sold to the greenies as a way to save the environment. Lots of people bought them for short city drives, battery would work and the engine would kick in for short periods to recharge. What they weren't told was once in a while they should take the car to highway speeds for a while so he engine warms and cleans itself out of condensate. What they would see is a milky white gel mass on the dipstick, oil cap/valve cover/head. Oil was equally crappy. Made the news, general complaints from misinformation (likely this was in the owner's manual...)
 

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2014 Outback 2.5 Premium w/Sunroof
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I change the oil in all of the vehicles twice a year, spring and fall. I don't go by mileage. The Outback is driven less than 9k miles a year. Just turned 36k. The motorcycle is ridden between 10-12k miles. The Jeep, (wifes) 12k miles a year.
 

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Yes and this is what likely meant by the "short trip not getting the engine to temp" comment. Also at play is where OP is from. It's cold in Wisconsin in winter, short trips there would be that much worse in winter.


I recall Ford fusion hybrids were sold to the greenies as a way to save the environment. Lots of people bought them for short city drives, battery would work and the engine would kick in for short periods to recharge. What they weren't told was once in a while they should take the car to highway speeds for a while so he engine warms and cleans itself out of condensate. What they would see is a milky white gel mass on the dipstick, oil cap/valve cover/head. Oil was equally crappy. Made the news, general complaints from misinformation (likely this was in the owner's manual...)
Yeah funny how bs gets passed around.

As a owner of one that sees two charges a day mon - fri not true
 

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2013 Outback 2.5i Convenience
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Yeah funny how bs gets passed around.

As a owner of one that sees two charges a day mon - fri not true
I imagine weather plays some part. I noticed your locale and I'm pretty sure it's not freezing for 4-5 months of the year there.
There was never some follow up on it.
 
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