Subaru Oil Consumption Problem & Repair

SubaruPistonRingSet

Genuine Subaru OEM parts only for these engines

The Subaru 2.0L, 2.2L and more common the 2.5L engines are great motors that last forever when maintenance correctly. Most Subaru owners are aware of the common oil leaks that develop as you start to put miles on them. Subaru owners seem to be well aware of the infamous headgasket failure on these engines also. These engines like to leak oil but they’re worth it to fix because they’re just so reliable. If you read the Internet you’ll find multiple articles about Subaru oil consumption problems and read about lawsuits or what not but what you don’t find is why these engines are having such a big problem with oil consumption in the first place. One thing that cannot be corrected which contributes to the high oil consumption rate is the way the engine is designed. The pistons are sliding horizontally about less than 6 inches above the oil pan and any bit of excessive crankcase pressure will cause piston to suck oil as they travel back and fourth right above the oil pan. If you have ever seen these engines torn down with the block split then you would probably understand what I’m explaining better. So, with that being said we know Subaru engines are prone to having oil consumption problems but if everything is working correctly then the engine should not burn the oil up. If you’re wondering why you don’t notice or see it burning and your car will just all the sudden be low on oil that’s because you will not see the oil consumption (oil burning) either. Most all of the burning oil smoke is covered up by the catalytic converters. Extended oil changed intervals are another huge contributor to this. The manufacturers have stretched out there oil change intervals to over 7,000 miles and conventional oil breaks down at 3,000. Then you add the Subaru oil consumption problem on top of the manufacturers recommended extended oil changed intervals where the oil is already broken down after 3K you have a oil consumption problem where you can damaged the engine from running it low. I recommend to all of my customers to check their oil level every 1,000 miles and to change the oil every 3,000 for conventional oil and every 5,000 for synthetic oil.

OilConsumptionPistonsRemovedDirty

Pistons removed before cleaned and serviced

SubaruPistonOilDrainHoles

Oil drain back holes get plugged, 4 holes on each side of the piston

What causes these already prone for oil consumption Subaru engines to start burning the oil? There are 4 to 5 oil drain back holes in the pistons that plug up not allowing the oil to drain through the oil scraper rings. The rings also get stuck in the piston not scraping the oil off the cylinder correctly. These two things cause the excessive oil consumption. The good news is that the pistons can be serviced without completely rebuilding the engine. Earlier I mentioned the infamous Subaru headgasket failure, we’ll when replacing the headgakets we can remove and service the pistons and piston rings without touching the rod or main bearings (is how the engine is rebuilt anyways). The engine block has piston access holes so just open the access hole, remove the circlip, tap out the wrist pin and then tap the piston out of the block. Now you can either replace the rings if needed or soak the pistons in carburetor cleaner dip for at least 24 hours then the rings should pop right out and don’t forget the clean the piston drain back holes. I have seen this problem develop at 60K, 80K and any engine over 100K always has this problem. Your Subaru 2.5Lwill need the headgaskets replaced sometime in its lifetime so monitor your oil consumption and mention this service.

OilConsumptionPistonsRemovedCleanedPic2

Pistons removed after cleaned and serviced

OilBurnedExhaustValves

Exhaust valves burned from excessive oil blowby

Here at MDH Motors we offer the service and I see a huge improvement in the engine drivability after these repairs. First off, you’ll probably need the exhaust valves re-faced (they get pitted and charred up from the oil burning) the intake valves and seats are usually okay. Second, the piston ring service restores loss compression so the engine will drive better, return the loss of power and get better gas mileage. I’m really impressed at how well theses engines run after this service, it will practically be a new engine for half the cost. Our headgasket repairs usually run from $1600, $1700 to $1800 and if you add the piston ring service while repairing the headgaskets it can be around $2500 or more. Keep in mind that these are just baseline costs and every job is different. Also we are a low overhead repair facility and have a discounted labor rate. Most other repair facilities cannot offer this service at this type of pricing. We specialize on these vehicles so we can do them more efficiently than most so don’t expect this type of pricing at your neighborhood auto repair shop. Also not very many repair facility’s are aware of this service and will just sell a complete new shortblock, which would cost $4000, $4500 to $5000 or more. This is what the Subaru dealerships are doing. They will not remove the pistons just replace the engine for the problem. In my opinion it wastes good engines which require a lot of energy to make so fix what you can to help save our environment instead of just replacing everything. Our automotive industry has became very bad for this, nobody wants to repair things anymore because everything today has to be right now, cannot wait for a rebuild just replace it. If your interested in this service you can contact us to schedule an appointment. Please leave your questions and/or comments below, thanks for reading.

This post was written by: Martin Hand

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Martin Hand

About Martin Hand

ASE Certified L1 Advanced Mastertech. Martin Hand has over 15 years experience in Asian and European Import Auto Repair. Specializing in electrical diagnosis, engine performance, AT/MT transmission repair/rebuild. Martin is also pursuing a degree in Computers Science & Information Systems starting at Portland Community College while he plans to transfer to OIT. Certified in Java application level programming, experienced with other languages such as PHP, Ruby, JavaScript and Swift. Martin has future plans of automotive diagnostic software development.

17 Comments

  • Victoria says:

    Hello, Thank you for this article. I really appreciate your knowledge and have learned a lot about what wa wrong with my car. I purchased my first Subaru last October, a 2013 Impreza Premium 2.0L manual transmission. I noticed oil loss, right away, but saw no oil leaks, which lead me to research oil burning in Subarus resulting in me learning about the oil consumption lawsuit. I went through the testing at the Subaru dealership (my oil light was going on 1,000 miles after an oil change so needless to say my car was a candidate for the new short block. Before they would replace it they had to do an engine tear down to prove the engine was not tampered with. That cost alone I would be reliable for if they did find that the engine was tampered with! Short block was replaced, and I am now left with burning oil smell for the past month. They say it takes time to burn off, all of this extra oil that got displaced. It hasn’t gotten any better. I plan on calling them back today to see if they can clean some more oil off wherever it is. I’m worried the oil went into places and is destroying parts of my engine.

    I’m glad to her that you think that Subaru’s have a great engine, but I finally bought a newer car and I hoped for something more reliable. I feel like I don’t want the car anymore even though I love the way if handles (although the pick up is not the greatest). I noticed that the Outback is not listed in the lawsuit. Are you aware if the engines in Outbacks are better?

    Thanks again!

    • Victoria says:

      I should correct, I didn’t see the actual lawsuit. When I say I didn’t see Outback listed in the lawsuit I refer to an article (not from Subaru) I read that didn’t list the Outback as cars affected by lawsuit. I’ll try to find the source, but I read many articles.

    • Martin Hand Martin Hand says:

      I believe it’s the 2.5l engines. The 6 cylinder and turbo engines don’t seem to have these problems. So it’s really depicted by what engine the Outback comes with.

      • Victoria Pilato says:

        Oh, I see. Thanks!
        If Subaru knows which vin #s are affected, why do they not let the consumer know, or fix the engines before selling them, in your opinion?
        My father asked his local mechanic about the Subaru oil consumption problem and his mechanic shared that Subaru is fully aware of the vehicles with the issue and provides other shops info on which cars are affected and a how-to on the repair. Seems a waste of time to go through all of the testing with Subaru first when they already know, no?

        • Martin Hand Martin Hand says:

          Yes but the manufacturer knows it’s a problem and only warranties when the customer is aware of the problem and willing to take the steps to have it taken care of. There are probably lots of these Subaru oil consumption engines on the road and never get the problem taken care of.

  • Paul Root says:

    Clear and helpful article. Thanks for writing and sharing your experience!

  • Gary Mengel says:

    I just lost an engine at 170k because I didn’t know the things you explained so well here. My oil ran dry and I threw a rod less than 3k after an oil change.

    I found your site while trying to figure out why it happened. Sure wish I’d known in time!
    Seems to me that this knowledge should be a LOT more common. I’m telling my friends!
    The dealerships should be recommending a valve & ring job as 100k maintenance, but then they’d be selling fewer new cars if they did that, wouldn’t they?

    • Martin Hand Martin Hand says:

      Sorry to hear that. For future knowledge any vehicle over 100,000 miles or even less should be checked for correct oil level in between oil changes. All engines will consume oil and you won’t see it burn because catalytic converter covers it up. Some engines consume more oil than others and after checking regularly you’ll know your engines consumption rate and how often you need to top it off.

  • Don Marcell says:

    I have a 2011 Forester 2.5x with 15,500 miles. It sound as if it experience oil burning issues it will be after 60-70K miles. and do all Forester engines develop this problem? What should be expected?
    Don, Mission, TX

    • Martin Hand Martin Hand says:

      It’s usually the later model Subarus that have this problem at low mileage. The earlier models wouldn’t develop this problem as common and would be higher mileage, likely over 100k

    • Syy says:

      Well, my outback 2010 had a blown head gasket at~79,000 miles less than 2 months ago and now we are experiencing the excessively oil consumption ( had to add like 3 quarts of oil with ~3,500 miles added after the head gasket done)

      Before the head gasket replacement we never had to refill the oil in between oil change at all.

      • Martin Hand Martin Hand says:

        There’s nothing that would cause oil consumption from replacing headgaskets unless the oil is leaking through the valve seals or guides or something not done correctly whith the cylinder heads or cylinder headgaskets.

  • Richard Garrison says:

    Thank you very much for this information. I live in Massachusetts so cannot bring my car to you but wish I could. I already had the head gasket replaced and the I experienced severe oil loss following the head gasket replacement. Dealer said “it has 120000 miles and is expected to loose oil”. I am now burning 2 quarts every 600 miles and am afraid I may have damaged the engine (low oil). Do you recommend rebuilding or buying one
    already rebuilt? Thanks, Richard Garrison

    • Martin Hand Martin Hand says:

      It really depends on the condition of the engine and who can repair it. If you don’t have an experienced Subaru technician that can fix the piston rings I would recommend replacing the short block. We buy our short blocks directly from Subaru and don’t recommend aftermarket rebuilds.

  • Robert says:

    How can Subarus be reliable when they commonly have oil consumption and head gasket failure problems.

    Vertical cylinder configuration used in most vehicles because of their design are not as prone to these problems.

    Costs of repairing head gasket and oil consumption problems are high and greatly increase the long term operating expense of Subarus.

  • Paul Grauman says:

    Thanks so much for the info on Subaru piston service, I have an old 90 Legacy wagon that has very high miles near 300K and does not burn oil (I rarely have to top up only after much driving time), but it does leak out of one side of motor and burn on exhaust on that side bit only badly when going up steep hills, it recently has gotten a little worse so I am thinking of just replacing valve cover gasket on that side and cover bolt bushing, do you recommend doing both sides even though leak only on one side and I have already replaced camshaft cover O-ring on back of head (on one side) My car has the EJ-22 which is much better about not blowing head gaskets and is non-interference so I would like to keep this car running good for as long as possible, even though has multiple electrical minor problems- window motors and/or switches, rear defroster, front defrost only works on bi-level, door handles,etc. I wired an ignition kill switch because my car got stolen with a Subaru key!@# and I also wired a Subaru headlight relay to provide a current boost to the starter solenoid because either the ignition key OR the solenoid contacts were not passing enough current or voltage to kick the starter over and I had the starter tested good at the parts store so I suspect the ignition key switch as this was also a problem on the older GLs and the ignition switches are from Nissan on most of these cars and are not good for 275+ in my opinion. Also the door hardware is also the newer style like Nissan and not as good as the old early 80’s GL’s which were super heavy duty and could even open the doors after a fairly bad accordian style body damage crash from the rear. Since car was stolen my turn signals have not worked so now I am working on getting good wiring diagram, and I suspect the flasher unit is shorted or worn out I have one lighting fuse in the under hood fusebox that blows when fuse in. The motor must have been changed out at some point because still has decent compression and doesn’t seem to burn any oil at all ! DO you no anyone with lots of Subaru wiring experience that I could consult or take car to if I can’t get electrical issues sorted out? I prefer low overhead shop or individual that worked out of home garage as I don’t have $ for high shop rate.

  • Amy Stokes says:

    I do not live in your area to where I can take advantage of your services but I felt I needed to let you know how much I appreciate this article. I have one of these engines and being someone who is not mechanically inclined it was nice to read something that I could understand. You also gave me great information on what parts I actually need fixed. I have made my list and will be talking to the dealership on exactly what they plan on fixing. This has already been a large problem for me. I bought this car a year ago and was told by my mechanic that it would be $5400 to fix the issues (which I cant afford). I strongly believe that the previous owner knew about the large amount of oil consumption and dumped the car instead of getting it fixed. When I came along who knows nothing about cars, the dealership then dumped it on me. Thank you so much for all this information.

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