This is a public service announcement for any forum members with a Subaru with the 3.6 motor.

Everyone passingly familiar with Subaru is likely privy to the 2.5 4 cylinder oil consumption problem. Thousands of blocks have been replaced by Subaru, after they failed their respective consumption tests.

I have a 2013 Outback with the 6 cyl. which we purchased new off the lot. From nearly the beginning, I noticed that I seemed to be adding an unreasonably high amount of oil to the motor between oil changes. I took it to the dealership twice to report, both times being told that it was “normal”. When I found myself adding up to 3 quarts between changes, I had had enough. With 93k on the clock, I took it to another Subaru dealer who admitted that it was odd for that particular motor. A test was initiated.

The results of the test showed 1/2 a quart per 1500 miles consumed under normal use. Subaru technicians agreed that we had a problem.

Luckily, we opted to purchase the 100k mile Gold plan warranty when we bought the car. The block was replaced under warranty, with us being out of pocket $100 for our deductible...minus the cost of the Gold plan, of course. To elaborate on what a short block replacement would cost, it was nearly $7000!

If anyone here has a Subaru with the 6 cylinder, be mindful of your oil consumption, and if you recognize that you seem to have the same problem, demand a full consumption test.

For the record, adding oil was the only warning sign we observed. There was no visible smoke, no rough running, etc.

This message has been edited. Last edited by: gearhounds,

Your car has a flat 6, not a V6. But glad you got it fixed under the warranty.

My 4 cyl ‘14 Outback hasn’t used much oil, but I’m glad I got the 100k warranty.

quote:

Originally posted by 2Adefender:
Your car has a flat 6, not a V6. But glad you got it fixed under the warranty.

My 4 cyl ‘14 Outback hasn’t used much oil, but I’m glad I got the 100k warranty.

Whoops and fixed; you’ve no idea how glad I am...a big reason I made this post.

Any other details on break-in, maintenance, or fluids used? Just collatin' data, so to speak.

I do a hard break in. As soon as practicable after purchase, I get the engine up to operating temp and then spend a good chunk of time on an empty highway (late night) running the engine steadily up to redline and then downshifting and engine braking it back down. Then I change the oil and filter out at 100 miles, 3000 miles, and switch to full synthetic oil at 7500. I make sure to vary the RPMs while the engine is under load for the first 1000 miles.

I'm convinced that a hard break-in mates the piston and rings to the cylinder more thoroughly, preventing oil from blowing by and burning during combustion. I've never had a car consume oil, and I generally keep my cars to 130k miles or more.

quote:

Originally posted by Aeteocles:
Any other details on break-in, maintenance, or fluids used? Just collatin' data, so to speak.

I do a hard break in. As soon as practicable after purchase, I get the engine up to operating temp and then spend a good chunk of time on an empty highway (late night) running the engine steadily up to redline and then downshifting and engine braking it back down. Then I change the oil and filter out at 100 miles, 3000 miles, and switch to full synthetic oil at 7500. I make sure to vary the RPMs while the engine is under load for the first 1000 miles.

I'm convinced that a hard break-in mates the piston and rings to the cylinder more thoroughly, preventing oil from blowing by and burning during combustion. I've never had a car consume oil, and I generally keep my cars to 130k miles or more.

We ran full synthetic with the first oil change at 3000, and subsequent changes at 7000, as per Subaru’s recommended interval. While I don’t push as hard as you, apparently, I never really babied it. It still pulled almost as hard at 93k as new, so missing oil really was the only symptom of an issue.

Our service guy, who was instrumental in pushing this through, informed me that in the last several years, Subaru intentionally designed the rings to allow oil into the combustion process to decrease emissions (didn’t understand that part), and the result with the 2.5 was a disaster. So much so that pretty much all Subaru dealerships keep 2.5 short blocks in stock. They did the same with the 3.6 evidently but mine was the only one he has handled. The rate of consumption with the 2.5 was in the neighborhood of 1 qt every 1000 miles, which is insane.

I don't think oil consumption is intentionally designed. If it was intentionally designed, then everybody--instead of a select few--would have consumption issues. I know that a specification for oil consumption is intentionally stated (I think my manual for my 2.5 states that 1 qt per 3000 miles is considered within tolerance). I've seen similar statements in manuals from my other cars, and I assume a lawyer put it there to manage the types of warranty claims that would come in. I think the service guy is just confusing the idea of a specification within tolerance, with an intentional design.

That said I'm glad that Subaru took care of you.

Didn’t they change/fix this in the current iteration of the 3.6 engine?

I have a ‘15 Legacy 3.6R. Oil is changed every 6000 miles with conventional oil. I always check the level after it’s changed and the morning before I go get it changed. I’m only at 70k miles and I have never had to add oil.

I have a Crosstrek. It has the baby 4, 2.0L. Any issues with these?

quote:

1/2 a quart per 1500 miles

I would never consider this a problem. A quart every 3K miles. If you were adding 3Q between changes then your oil change strategy needs work, that's 9K oil changes on a little motor with not so much oil in the first place! I'm frankly stunned you got someone to pay attention to that in a 100K motor. In just about every battle I've had about oil the floor on fixing stuff is 1qt per 1K. Which I consider excessive but most mfg. do not.

Have a 2018 3.6 so will keep my eye on this. Had oil consumption issues in my 2011 Audi A4, fought with Audi for over a year and finally got new rings and pistons, don't particularly want to do that again.

Boxer engines are typically oil consumers until they break in, and even then to a degree.

I have a boxer motor in my moto, it has nickel boron sleeves, so break in is difficult. I used dino oil in it till 18K, then switched to synthetic. BMW suggested running on dino oil until consumption reduced.

Glad you got a replacement motor.

quote:

Originally posted by Snapping Twig:
Boxer engines are typically oil consumers until they break in, and even then to a degree.

Yup, the Porsche 911 motor was notorious...but then it was oil cooled

I had a 911SC and 1qt/k miles was considered the norm

quote:

Originally posted by hrcjon:

quote:

1/2 a quart per 1500 miles

I would never consider this a problem. A quart every 3K miles. If you were adding 3Q between changes then your oil change strategy needs work, that's 9K oil changes on a little motor with not so much oil in the first place! I'm frankly stunned you got someone to pay attention to that in a 100K motor. In just about every battle I've had about oil the floor on fixing stuff is 1qt per 1K. Which I consider excessive but most mfg. do not.

I have never had a vehicle consume a full quart every 3000 miles, and 3 quarts in 7000 is ridiculous. This mileage is what Subaru recommends oil changes at for full synthetic oil. Time will tell if the new short block does what the tech says, which should be drastically reduced consumption.

What set off the test was the fact that this particular motor had been consuming excessively from the beginning. The dealership where it was purchased refused to take it seriously or it would have been addressed earlier. I can also say that the engine consumed oil at a faster rate as mileage increased, and not within any kind of spec. I didn’t consider it normal, and neither did Subaru.

quote:

Originally posted by 9mmepiphany:

quote:

Originally posted by Snapping Twig:
Boxer engines are typically oil consumers until they break in, and even then to a degree.

Yup, the Porsche 911 motor was notorious...but then it was oil cooled

I had a 911SC and 1qt/k miles was considered the norm

Oil cooled is a completely different beast.

quote:

Originally posted by Snapping Twig:
Boxer engines are typically oil consumers until they break in, and even then to a degree.

I have a boxer motor in my moto, it has nickel boron sleeves, so break in is difficult. I used dino oil in it till 18K, then switched to synthetic. BMW suggested running on dino oil until consumption reduced.

Glad you got a replacement motor.

Mine seemed to do the opposite; as it broke in, consumption increased dramatically. The weirdest thing was there was never and indication from the performance or emissions. No visible smoke, even at cold start up. No odor of burning oil.

Subaru and their motors. Prior owner and wish they’d get their shit together on their motors.
There was a class action lawsuit on them for oil consumption. Google fu.

From 2015 forward the EZ3.6 is not known for consumption problems.

Prior to that SOA used low tension rings to decrease friction leading to increased mileage. It was a disaster.

Stories abound on subieforum of people taking their 2.5 and 3.6s to the dealer relaying the consumption concern. The dealer says that they never of that before and offers to do a consumption test.

Dirty secret - the dealer overfilled the engines so when you returned, the dealer would say the oil was between the lines and all is ok.

I drive a 2016 3.6 and have zero alarming concerns. Uses about 1/3 of a quart over 6k miles. I do the changes myself.

I have had the oil tested and none of the results raised concerns with the testing company.

Up to a certain year the concerns were real, just like the CVTs before 2016 received a 100k or 1 year extended warranty outside if you were outside of warranty.

quote:

Originally posted by Flashlightboy:
From 2015 forward the EZ3.6 is not known for consumption problems.

Prior to that SOA used low tension rings to decrease friction leading to increased mileage. It was a disaster.

Stories abound on subieforum of people taking their 2.5 and 3.6s to the dealer relaying the consumption concern. The dealer says that they never of that before and offers to do a consumption test.

Dirty secret - the dealer overfilled the engines so when you returned, the dealer would say the oil was between the lines and all is ok.

I drive a 2016 3.6 and have zero alarming concerns. Uses about 1/3 of a quart over 6k miles. I do the changes myself.

I have had the oil tested and none of the results raised concerns with the testing company.

Up to a certain year the concerns were real, just like the CVTs before 2016 received a 100k or 1 year extended warranty outside if you were outside of warranty.

I suspect I was getting the truth from the tech at Subaru; first that the issue was established (and known) and that the issue will no longer be present due to the installation of the new block. Now the lack of assistance at the first dealership makes more sense as well.

quote:

Originally posted by gearhounds:

quote:

Originally posted by 9mmepiphany:

quote:

Originally posted by Snapping Twig:
Boxer engines are typically oil consumers until they break in, and even then to a degree.

Yup, the Porsche 911 motor was notorious...but then it was oil cooled

I had a 911SC and 1qt/k miles was considered the norm

Oil cooled is a completely different beast.

Yep. Oil and air cooled boxers have to be 'looser' because of their heat dissipation and expansion characteristics.

quote:

Originally posted by pedropcola:
I have a Crosstrek. It has the baby 4, 2.0L. Any issues with these?

The 2.0 has it's own issues. Not every motor is effected so Google away.