first thing that occurs is that you're cooking out some fuel dilution on the trip down, and nothing left to cook out on the way back. Do you short-trip much when you're not driving to TX?So here's an interesting one I can't seem to figure out and isn't making much sense to me...
I have a 2016 Outback 3.6 and love the car for what it is. Other than this "issue" the motor and the rest of the car are in great shape with plenty of abuse and 83k miles with most of any needed work or maintenance done by myself and have had since new. Oil changes have always been consistent at 6k miles give or take on synthetic when back in North Texas, then when moving here to Colorado at 5k for Syn and 4k to 5k for "conventional" blend depending on driving. So never any really long OCI's or even pushing it with this car in its life.
Anyway, the motor doesn't really burn much oil at all during an entire OCI...MAYBE 1/4 a quart if there's lots of off roading or mountain driving during but even then it's only sometimes and is really a non issue.
Here's the head scratcher I can't figure out....I still drive back and forth to Dallas from Denver every 3 to 4 months consistently. On the drive DOWN to Texas, I'll ALWAYS burn between 1/2 a quart to 3/4 of a quart of oil. I'll top off when I arrive of course the next day, however on the drive back to Denver the motor won't burn a single drop. What point I am in the OCI doesn't matter it seems to always happen to the same degree, and the brand or type doesn't seem to matter with the exception that I used a little bit less than usual on the drive down with a HM blend.
It's definitely not a situation where the oil has been short tripped (my car rarely is) for a while then burns off excess fuel, water etc. The motor barely burns any oil during an OCI or even long highway drives unless it's the drive down to Dallas and only then one way.
I can't figure it out and even fellow mechanic buddies can't seem to figure it out. Could it have something to do with changing altitudes or pressures going DOWN only? And where could it "be going"? Past the piston rings and into the cylinder? And then why? lol
The motor obviously seems just fine otherwise and as long as it's topped off afterwards has no issues. I've never even experienced a low oil light in the thing...but this one way drive is the only thing it doesn't seem to like. Anyone here have any experience with something like this before by chance?
I think the car is burning off water and fuel in the oil on the first trip..Oh that's an EASY one.
And a sustained trip, You will be burning off the sump dilution of water and fuel, then having exercised the engine you will have cleaned up the rings a bit.
Cars that " don't burn a drop" actually DO, its unavoidable.
The missing lube is replaced by gas and water and other blowby products.
HTH,
- Ken
Ill be honest with you, I have never seen a Boxer engine that didn't use oil.So here's an interesting one I can't seem to figure out and isn't making much sense to me...
I have a 2016 Outback 3.6 and love the car for what it is. Other than this "issue" the motor and the rest of the car are in great shape with plenty of abuse and 83k miles with most of any needed work or maintenance done by myself and have had since new. Oil changes have always been consistent at 6k miles give or take on synthetic when back in North Texas, then when moving here to Colorado at 5k for Syn and 4k to 5k for "conventional" blend depending on driving. So never any really long OCI's or even pushing it with this car in its life.
Anyway, the motor doesn't really burn much oil at all during an entire OCI...MAYBE 1/4 a quart if there's lots of off roading or mountain driving during but even then it's only sometimes and is really a non issue.
Here's the head scratcher I can't figure out....I still drive back and forth to Dallas from Denver every 3 to 4 months consistently. On the drive DOWN to Texas, I'll ALWAYS burn between 1/2 a quart to 3/4 of a quart of oil. I'll top off when I arrive of course the next day, however on the drive back to Denver the motor won't burn a single drop. What point I am in the OCI doesn't matter it seems to always happen to the same degree, and the brand or type doesn't seem to matter with the exception that I used a little bit less than usual on the drive down with a HM blend.
It's definitely not a situation where the oil has been short tripped (my car rarely is) for a while then burns off excess fuel, water etc. The motor barely burns any oil during an OCI or even long highway drives unless it's the drive down to Dallas and only then one way.
I can't figure it out and even fellow mechanic buddies can't seem to figure it out. Could it have something to do with changing altitudes or pressures going DOWN only? And where could it "be going"? Past the piston rings and into the cylinder? And then why? lol
The motor obviously seems just fine otherwise and as long as it's topped off afterwards has no issues. I've never even experienced a low oil light in the thing...but this one way drive is the only thing it doesn't seem to like. Anyone here have any experience with something like this before by chance?
How many have you owned? I think we are up to #7 or 8 - I lost countIll be honest with you, I have never seen a Boxer engine that didn't use oil.
Yes the trip could also be freeing up gummy rings along the way.Next trip. Chg oil before you leave. Might be interesting to see if it still burns oil the first direction.
One, 2006 Forester, used a quart every 3k miles. Belonged to many Subaru forums and it was a common topic.How many have you owned? I think we are up to #7 or 8 - I lost count
In my experience over the past 30 years, I could agree with you on that; but our last 2017 Crosstrek 2.0L and the current 2021 Outback 2.5L use nothing.
The older EJ likely needed heavier oil than the junk conventional 5W30 used back then .
Then there was a period of imporperly machine valve guides and then piston and ring issues - all with TSB and campaigns