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Yes. It's normal for some modern engines to consume oil between changes. So long as the usage is predictable and not accelerating it's something to be expected.

It's really not necessarily due to a manufacturing defect so much as a miscommunication and marketing problem.

Let me explain.

Back in the old days, an engine that burned oil was ready for the scrap heap. Either the rings were shot or valve guides worn and it was ready for a rebuild...or, more likely, you traded it off to let some other poor sap deal with it.

Heck, once up on a time I operated a diesel power plant. Those 16 cylinder Cat D399s would sometimes require 4-5 gallons of oil per 12 hour per shift. Tangent: the diesels experienced more blow by and oil consumption at low power levels than they did when operating at maximum load.

Anyway, that mentality has stuck with us. Any engine that burns oil is bad.

However, in the quest for fuel efficiency, some manufacturers have looked for ways to reduce internal friction and have thus loosened up tolerances somewhat. Subaru seems to be one of the guilty parties. Although we see gains in miles per gallon, it comes at the expense of small amounts of oil finding its way into the combustion chamber.

Of course, if Subaru (or anyone else) admits that their engines burned oil, their attempts to rationalize the issue will be drowned out by cries from owners yelling "crappy engineering". Which, if you look at it from the our conventional way of thinking, seems legit. That leads to bad PR and a decline in sales. So, they keep their mouths shut and, when customers complain of oil consumption, the dealership keep tabs on it and says "it's within the acceptable range", whatever that means.

Yes, this sucks. But, in all fairness, we're saving gobs more money on improved fuel economy than the $10 or so it costs us to top off the oil between changes. We should probably just come to terms with it or shop elsewhere...

Anyway, I've taken a liking to this Australian bloke's Youtube channel. He uses humor (NSFW) to explain this and other issues.

 

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This guy makes some of the greatest, straightforward videos that I've seen in a while. I actually really enjoy them, thanks for posting this!
 

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Also burning oil makes HP
We burn a little on our race cars to keep them running cool and make more power by sealing off the rings for more compression.
 

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If you search Subaru oil consumption you will find some owners have Subaru's that consume more than a little oil between oil changes, several quarts in some cases. That much oil consumption certainly isn’t beneficial for the engine.

Subaru has been sued for excessive oil consumption, they lost the case and are doing several things to solve the problem. This applies only to specific models and years and does not apply to 17 Impreza models.

The recommended oil change frequency has been reduced to 6k miles or 6 months. The power train warranty increased to 8 years or 100k miles, whichever occurs first. Some people are getting new piston rings, others are getting new short blocks.

My son has 13-14 Crosstrek that used too much oil, he got a new short block. It was done a few months ago and so far seems ok. I asked if it was new or a refurbished block, he wasn’t sure. One of his friends with a Subaru also got a replacement engine block.

I know I’m talking about cars that are older than 2017 models, but some people on our forum have reported oil consumption. Our cars are too new to really know if they will have oil use problems. So far my Premium edition with CVT is still above the full mark as it was when purchased, but it has been driven only a little over 1100 miles, all short runs.

Anyway, I realize a car must use some oil to live, but over a quart between changes is too much for me. I do not agree that running lots of oil through an engine has any useful benefit, unless you like changing plugs.


Clifton




 

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I would agree with and disagree with the OP on this topic. My background is that for almost 20 years I have worked as a service tech for Harley-Davidson (Certified Master Tech, Polaris Offroad vehicles, Victory Motorcycles, Indian Motorcycles and Polaris Snowmobiles Gold certified Tech).
All engines will burn/use a small amount of oil, most through the crankcase breather system. What is a small amount? I would say less than a quart/liter per every oil change interval.
My 17 is barley below the full mark at 3000 miles.
Anything more than a quart I would not stop contacting the dealership and Subaru Customer Service.
 

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Discussion Starter #6
I would agree with and disagree with the OP on this topic. My background is that for almost 20 years I have worked as a service tech for Harley-Davidson (Certified Master Tech, Polaris Offroad vehicles, Victory Motorcycles, Indian Motorcycles and Polaris Snowmobiles Gold certified Tech).
All engines will burn/use a small amount of oil, most through the crankcase breather system. What is a small amount? I would say less than a quart/liter per every oil change interval.
My 17 is barley below the full mark at 3000 miles.
Anything more than a quart I would not stop contacting the dealership and Subaru Customer Service.
Yeah. A quart is about all that I'd probably tolerate as well. That's what my new 5L F150 used over the first 1000 miles (with most coming during the first few hundred). But it holds 8 quarts and didn't register as a scary loss on the dipstick. Nothing 4000 miles later, though.

What is the upper limit of Subaru's "normal" range? Anyone know?
 

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According to the owner manual, changing the oil and filter requires 4.7 US qt. (4.4 liters, 3.9 Imp qt.) Adding oil from low mark to full 1.1 US qt. (1.0 liter, 0.9 Imp qt.).


Clifton
 

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I once had a VW Passat that was burning a quart every 800 miles. The service manager at the VW dealership said that was "within spec". Last VW I ever purchased, and ever will. I was out well before the current diesel debacle.

Subaru has had a huge problem with this in (what are now) older cars. It came along after the head gasket issues on the Outbacks (which seem largely to have been resolved). Yes, they will replace an entire engine just to stop an oil consumption problem as other posters said - pretty drastic step. Hope that has been resolved, but there are folks with new Foresters that are reporting consumption issues . . .
 

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My other car also has a boxer engine, it's a 1996 Porsche 911. I have been told by many people that a little oil consumption on a boxer engine is normal and I keep a litre of oil in the car just in case.

On a boxer engine oil can seep past the rings when the car is not running for any length of time, in fact we are told not to worry about that grey or white puff of smoke from the exhaust on startup.

Excessive oil consumption is another matter and can mean a top end rebuild is due or perhaps a new set of rings.

Don't sweat it. :wink2:
 
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