All Wheel Drive Auto: Independent Seattle Subaru Service


Why Changing Your Oil In Your Subaru Every 3000 Miles Is A Must For Most Drivers

I often have conversations at the shop about oil changes.   There are a lot of different opinions and as a result a lot of confusion.   But the reality is that oil changes are a very necessary part of your Subaru’s  longevity or lack thereof if not done as often as needed or done with poor quality parts.

All car manufacturers have a normal and severe maintenance schedule, and if you’re driving habits fall into the manufactures definition of normal then maybe it makes sense to follow that schedule.  But if you use your Subaru or any other car you drive in any fashion other than starting it up getting on the freeway where you travel at freeway speeds until you reach your destination where you shut it off and then repeat this use in this fashion the majority of the time you drive it, than you do not fall into the normal maintenance schedule.   The real reason for the different maintenance schedule is to give the appearance of having lower ownership costs.

I have heard to many times that a customer thinks that changing the oil every 3000 miles is something a well known lube center dreamed up.   The marketing of the 3 month or 3000 mile oil change service was taken to new heights by the lube centers, but they sure didn’t dream up the idea.

When I started in auto shop we learned that the hardest thing an engine goes through is the heat of the summer and the cold of the winter.   You should start the summer season with fresh engine oil and once the summer is over you should change the contaminated oil out of the engine as the excessive heat can be detrimental to the effectiveness of the oil.  Conversely the engine should start the cold of winter with good fresh oil and sometimes a thinner grade of oil should be used to help the cold oil get to the top end of the engine quicker.   Once the winter season is over the sludge that once was oil should be drained out.   There you have it, the 4 oil changes a year your car should have.

I know there are companies out there telling you that if you use their synthetic oil you can forgo the 3000 mile thing.  I have heard customers and read forums on line talk about having an oil analysis done to prove the oil was still ok 5000, 7000 and even 10000 miles from new.   But is the oil filter still working?   Does oil that still has lubricating properties mean that it is ok?  While synthetic oil can stretch out the oil change interval the level of the oil should be monitored very closely regardless of the product used.  The other fluid levels in the car such as the coolant need to be topped off periodically as well and the tires inflated too.  If the service interval of the oil is stretched out the service of the rest of the car suffers as well.

How does the whole system work?   Oil lubricates and cools the engine; in fact the oil in your engine is about 1/3 of your engines cooling system.  As the valves open and close, the pistons move up and down it is oil that keeps the moving parts moving easier.   The engine is the hub of your car it all starts with the rotation of the engine, the easier the job the engine has of all of its parts moving freely the easier all of the parts the engine is in turn supposed to turn will move as well.   Yes slacking on oil changes poses ramifications to more than just the engine itself.

As the engine is injecting fuel into the cylinders to provide the explosion that powers the engine not all of the fuel is burnt, we do not achieve 100% combustion with the internal combustion engine.  The excess fuel slides past the piston rings and into the crankcase where it mixes with the engine oil.  Over time a lot of excess fuel can end up in the crankcase.   The fuel mixed with the oil can degrade the lubricating properties of the oil and lower the flash point of the oil as well.  Another words the longer the oil is in the engine, the more fuel it collects, and as this oil fuel mixture is used to lubricate the parts in the combustion chamber the more likely it is to burn away, out of the engine into the exhaust and out the tail pipe.  Over time the engine can burn a significant amount of engine oil.  Next fuel is a solvent that can and will eat away at seals and gaskets causing leaks that will need to be repaired.  Try pouring a thimble full of gasoline on asphalt and watch how easily the fuel eats away at the road.  Imagine what contaminated oil can do over time to the head gaskets in your Subaru.

There are systems in place designed to help remove the fuel from the engine oil, one is the positive crankcase ventilation system or PCV, the other is called the breather hose, or breather tube.  On a Subaru you will find a rubber hose attached to each valve cover gasket and then traveling up to the air intake tube.

Here is how the system should work, once the engine oil gets up to temperature the fuel vapor and contaminates can separate themselves from the engine and this vapor can be pulled back into the intake manifold and be re burnt or introduced back into the combustion chamber.   This helps clean up the engine oil and prolongs the oils life.

Here is the problem with this, if you get in your car and make short trips, or spend a lot of time “idle” in traffic this is never going to happen in your car.   And this is why maintaining your Subaru based on how YOU use it, is the only way to get as much value out of your car as possible.

Ask yourself if you think the car companies really want you to keep your car 10 years take care of it and have it last or buy another car every 4 years.

Next imagine that you own a factory with rows of equipment that all needs maintenance on a regular basis or the chance of the equipment failing and costing you money and down time will greatly increase.   Do you think most informed business owners will follow a strict schedule to maintain the equipment, thus keeping profits high and replacement costs down or rather roll the dice and stretch it out.    The similarities are there.

Except that we often get caught up in this crazy notion of blue book value dictating how much  money we should put into a car instead of looking at replacement costs or the total value of keeping what we already own in good shape so it will last, but that is another article to write at a later date.

Here are some pictures of a 1997 Subaru Outback 2.5l Engine with less than 100k on it that had engine oil leaks at every possible location.  The owner admit tingly changed the oil every 7500 and has no idea what kind of oil was used.  The sludge build up is not good at all.  Over ten years the $500.00 or so in savings by stretching out the oil changes has been more than made up in mechanical repairs.

More Subaru cylinder head sludge build up
More Subaru cylinder head sludge build up
Sludge build up in a Subaru engine
Sludge build up in a Subaru engine
Subaru 2.5l cam seal leak
Subaru 2.5l cam seal leak

Subaru cylinder head Subaru 2.5l sludge

Thanks for reading



135 Responses

  1. Unbelievable genuine information that we can’t get from anywhere else!
    What are your thoughts about fully synthetic High Mileage oil, if it is on sale for a equal to straight synthetic oil price? Can it hurt a 160k base impreza?

    1. Hey Zhan,

      Every situation is a little different. Engine wear and use of the vehicle being the predominate drivers here. If you have a Subaru that doesn’t seem to use oil in between oil changes no matter what you seem to use, than by all means be price sensitive and have no worries. If however your Subaru falls into a situation where it seems to use a little oil with brand X and not so much with brand Y your better off sticking with what works the best over what costs the least.

      We do use high mileage synthetic BLEND as the go to in the NA EJ engines. See no issue with using full synthetic but it just doesn’t change the interval if the oil filter is in by pass mode.

      Hope that helps


  2. HI Justin,
    I have a 2009 Imprenza that I just recently bought. I’m going for an oil change, as I have put on 3,000 miles. The previous owners have used the conventional blend. It has 181,000 miles, and I was wondering ,would there be any benefit to change to Synthetic? Also ,for the winter should I go to 5w -20.

    1. Hello Joseph,

      Congrats on the New to you Subaru.

      I would stick with a 5w30 Blend. As far as 5w20, if you live in an area where the climate dictates a lighter oil should be used due to harsh winter conditions yes, if not just stick with the 5W30 Blend.


  3. Thanks for your reply Justin!
    I’ll be replacing the fuel pump soon, with a genuine Subaru assembly. The starter is starting to get dodgy – I had to smack it the other day to get the car started. Original starter – 324K on the clock now.
    We need a good Subie specialist like you where I am in New Jersey. I’ve done everything on my car since it was new, but it would be nice to have a trusted mechanic available.

  4. Hi Justin,
    I stumbled on your website when searching on how to replace the rear wheel bearings on a 2005 Forester. Thanks for all the great information! My 2005 gets 3-4 oil changes a year at 5-6K intervals. I’m one of those rare cases that doesn’t fall under the ‘severe’ usage category as the majority of my driving is freeway. The fact that my first wheel bearing went after 320K shows what an easy life it has! The rear brake shoes are original too. The car has been fed Wal-Mart conventional oil for most of its life, and it only consumes a quart of oil between changes, even at 322K miles. (not km) The passenger side HG started leaking oil at 250K and they were replaced by me at 290K. While I had the engine out, I replaced all the gaskets and seals. There was no sludge in the heads, just the typical light brown ‘patina’. I’ve been using 10W-30 in the summer because of the age of the engine and 5W-30 in the winter (NJ) for proper oiling. I always let the engine warm up until the temp gauge moves before I drive. I am moving towards 3-4K oil changes now because I’m sure the oil is being contaminated more quickly because of the age of the engine.

    As a Subaru expert, do you think I should proactively replace the fuel pump? I’ve replaced alternators, water pumps and thermostats every 100K with the timing belt, but the fuel pump is original. I scoped the power lead and the waveform looks good, but those carbon brushes must be wearing thin by now for sure! My understanding is that the fuel filter is part of the in-tank pump assembly too.

    1. Hey Trent,

      Great post!

      So yes you are correct, the fuel pump is actually a wear item and even though they are more of a replace when the fail kind of a thing for the average owner you are correct to preemptively think about doing this. At 322k its due, if you wanted to see where its at you might use an amp clamp on the lead to the pump, its kind of a pain to make that happen however, but looking at start up draw VS running amps might better tell you over just wave form, but that’s still a good test.

      Hope that helps


  5. Hi Justin, thanks for that. As it happens we also have a 2011 Forester that has already had a warranty short block replacement. I’ve been using 0w30 Mobil 1 in both the Crosstrek and the Forester – it works out because the Forester takes a little more than 5 quarts and the Crosstrek a little less. Based on your advice I’ll switch back to 0w20 in both as soon as I use up the remaining 0w30. This will save me money because Costco sells 0w20 but not 0w30.

    Those 6 Star filters look like they might actually be Tokyo Roki. Have you ever cut one open to compare?

  6. Hi Justin,

    I have a 2019 Crosstrek with about 17000 miles. I did the first three changes at 500, 1500, and 3000 miles, and all subsequent changes have been at 3000 mile intervals. I alternate between dealer and DIY so that the dealer sees it every 6k for warranty record purposes.

    The manual specifies 0w20 synthetic. I find the engine is a little less clattery with 0w30 synthetic, but that weight is hard to come by and am considering taking the next step to 5w30. Manuals for other regions outside the US say 5w30 is allowed. Presumably the FB20D engine is the same worldwide. Would you agree that 5w30 full synthetic is okay for this engine? As to the filter, I’ve been using Tokyo Roki black filters, but those are also hard to come by, and the blue Fram-made OEM are not very good. What aftermarket filter do you recommend?

    Finally: How do you feel about Costco’s Kirkland synthetic oil? I keep hearing good things about it but I’m curious about your opinion.


    1. Hey Jon,

      I know the 5w30 thing comes up a lot, I just don’t generally suggest it here in the Northwest where I live for use in my customers cars, nor would I use it in any car still covered under Subaru’s powertrain warranty.

      We have a couple that we have seen some oil starvation with early on in the 5w30 in place of 0w20 thing. 2011 Forester that a customer would not use what he felt was water and at 35k the left side intake cam seized. Subaru would not warranty due to the maintenance history of 5w30. We replaced the engine at the customers expense. We have a few with similar stories. I’ve ran 5w30 in some other FB’s and the fuel economy dropped and when viewing the AVCS readings before and after while not enough to set a code/check engine light were not really where id like to see them. This over a prolonged period of time can be problematic.

      I have not done the time to blueprint the FB VS the EJ in terms of oil passage specs etc. to try and understand all of the differences. I wish there were more hours in the day.

      As far as the oil filter this is what we use here, its the closest we can get to the Tokyo Roki. Its a great filter, way better than the Blue Fram from SOA

      If I ever can come at the 5W30 in the FB from a science and fact based position I will post that information.



  7. Justin,

    I just purchased 2021 turbo 2.4 Outback Touring XT. Love the car. My first Subaru. Drive a lot in stop and go traffic, 30 miles/day. Dealership says change oil 5K. Would like to keep this car for a longer period . Your advice would be most welcomed…

    1. Hey Steven,

      Great question! Its always my advice with any Turbocharged Subaru to look to change the oil at 3 Months/3000 mile area. Definitely for the first, after that if you want to go to say 3500-4000 make sure you are checking it for level and condition. I would stick to as close as 3000-4000 miles and every 3 months. If its my car its 4 times a year.

      I also plan on buying the 2022 Wilderness with the 2.4T as well, kind of cant wait!



  8. Hi Justin,

    On slightly different note, I changed my transmission fluid in a 2012 4EAT by doing a drain and fill on it at 90 K miles for the first time. It is now coming up on now has 105,000 miles and I was thinking of doing another drain and fill at 105k and then every 30k. Do you see anything wrong with this approach at this point?

    ps: The trans fluid is light to medium brown, but not black or burnt. It was like that at 90k as well.

    1. Hey SS,

      That’s a great Plan, you cant do damage by changing the fluid. We usd to actually change the Transmission fluid in the first Version of the E4AT Transmission every 15k back in the day.


  9. Hey Justin,

    I own a 2011 Impreza 2.5i premium w/automatic transmission with approx 105k miles for five years now and am planning on keeping it for as long as possible. I’ve done oil changes religiously at 3000 miles since owning it with whatever oil I could get on sale/stock up on (lately using Costco Signature) and have very frequently changed out other fluids as well, I think you would be proud to see my Impreza should I ever visit your shop!!. My question is regarding high mileage oil. I am 105k miles and using up what I have left in my garage and considering switching to high mileage oil. There are no oil leaks whatsoever (I did my timing belt and everything looked really good) although my car does consume 1/2 -3/4 quart per oil change. I am worried about the so called seal swellers that they say Hm oil has, or is that a myth? Should I use it even though there are no leaks? Will it swell up my seals so that I have to keep using it or soften them up to the point that they fail?Could you dispel some of the myths about it? Thank you so much

    1. Hello Anton,

      Here is what we use at the shop for your era Subaru. Castrol 5w30 Synthetic blend, its also sold as high mileage oil. Its really the absolute best choice for the Subaru you drive. HM oil is typically about being a blend with a better additive package to help out with consumption as the engine wears, its not about trying to resolve oil leaks. Give it a shot.

      Hope that helps


  10. Hi, I appreciate all the feedback you give as it is very useful. I bought new a 2013 Subaru Legacy but have the optional 3.6L H6 engine to avoid the head gasket issues on the four cylinder with that odd coating they put on it. I now have 105,000 miles on it changing the oil religiously every 5000 miles and changed the spark plugs at 90,000 miles (I know, longer than recommended but they were fine when I removed them although nearly worn out with the points being worn but the engine was running fine). I don’t think I am doing anything wrong and I changed the “lifetime” transmission fluid in my five speed JATCO unit along with the transmission filter at 95,000 miles. I have had no issues at all (it briefly burned a little oil at 40,000 but stopped by 50,000). My simple question is do you see anything wrong with what I am doing? I don’t believe so but value your opinion. Thank you.

    1. Hey Samuel,

      So the first thing id suggest is to not wait so long on the Spark Plugs, its not just about the plugs, you can make the coils work harder with worn plugs and they are not cheap. For the rest I don’t really know how your using but if the oil is still full and not to dirty and your pretty sure the oil filter isn’t in bypass mode prior to you changing it I would stay the course. I will add the trans fluid should be done every 60k on the 5 speed behind the H6. Subaru doesn’t offer a lifetime fluid. Even the CVT needs servicing in the 2013 H4.

      Hope that helps and you made a great choice of cars


      1. Thank you Justin.

        I plan to change the plugs earlier and I ignored the owner’s manual on changing the “lifetime” transmission fluid because I did not believe what it was saying (it just says “Inspect” it every 30,000 miles – whatever that means for the CVT and the 5 speed I have). When the fluid came out it was still red to my surprise but will follow your advice and change it at 150k (60k later). Thank you for your advice.


        1. Hey Samuel,

          To be clear the “I” in the Owners manual does not mean Inspect, in fine print it states “I” = Inspect, correct or Replace as necessary. Kind of misleading but every manufacturer does it.

          Hope you get years of solid use!


          1. Hi Justin,
            Just an update. Now have 121,000 miles. Recently the master brake cylinder went despite the fact I did replace the fluid as recommended. Also the rear wheel bearing are going as well (will replace them this weekend). I was reading online that the wheel bearing are a weak point in Subarus which I did not know – but seeing reports that people lose them between 30,000 and 50,000 I feel fortunate my lasted just over 120,000. Do you see that as a problem as well on many Subarus? Thank you.

          2. Hello Samuel,

            While we do a fair amount of wheel bearing replacements on Subarus I don’t think its really much different than on any other CV axle/Macpherson strut equipped Vehicle. There are also some Subaru models that do have more issues than others such as pre 2009 Foresters as an example and the primary offender being the right rear.


  11. Hi Justin, any issue with using synthetic 5w-30 instead of 0w-20 on a 2012 Forester 2.5 engine? Goal would be to reduce oil consumption. Thanks!

    1. Hi SS,

      The engine was designed for Ow20, its just not a good idea, ive answered this Question at least 50 times on the site. The internal tolerances for the engines requiring 0w are different than the ones using 5w.


  12. Howdy Justin, 2001 H6 3.0, 170K, runs great, some oil leaks but never enough that I have to add oil between oil changes, have always used conventional 5W 30. The shop I have used has now made ‘synthetic blend’ their primary oil. My concern is introducing synthetic Molecules – will it make my leaks worse? I read stuff like this online: “ while synthetic oil won’t create a leak, it will find one. Its streamlined molecular structure has no mercy for cracked or otherwise marginal seals. The oil and its additives may even clean deposits from the engine, which is good — unless those deposits are acting like spackle on questionable seals.”
    In your opinion am I OK going to synthetic blend, or should I find a different shop willing to use conventional oil? Thanks!

    1. Hello Rich,

      We have always used 5w30 Synthetic Blend as our standard oil on the H6. Keep in mind that the difference from conventional to blend is really more about the refining process. It’s not that much different and I really believe you will be fine. Just stick to the Schedule you have been following which will hopefully is 3 months 3000 miles regardless of the oil.

      Hope that helps


  13. Ive read all of the page.
    Thank you for this.
    I will be purchasing a fully rebuilt 2006 outback XT.
    I have agoraphobia and have a near impossible time leaving the house…
    I drive 10 miles round trip to work only every other day.
    Last car i had i put only about 3000 miles in 2 years.
    I live in mountain climate average temp is winter 10f-40f summer 40f-97F.
    The temperature here changes often.
    If i use the best rated full synth oil (motul)
    and change every 3000 OR every 4 months (not 3) will this still be optimal?
    Changing every 3 months for me means changing at 308 miles of use.
    If i change every 4 months i will be changing oil with about 410 miles of use.
    Mind you all is short city trip with a 20min freeway drive once a week or so to get up to temp and clear it out.

    So with my special case of never driving the car and using the best full synth oil is 4 months ok to wait? I want to be extra good to it yet do not want to waste oil and money.

    Thanks much for all you do here.
    Mr. Servo

    1. Hello Mr Servo,

      If you’re really going to do the 20 mile freeway trip let’s do this;

      Make sure you start out Winter with fresh oil, and also start out Summer with fresh oil. Every 6 months. If you see the oil is excessively dirty at month 4, change it and smith to three oil changes a year.

      Hope that helps


  14. Hi Justin,

    I drive a 2004 Subaru Outback. I bought it in 2018 I believe. Runs great, about 190k miles but the engine was replaced by the auto shop I purchased the car from (not sure when). I have always gotten my oil changed every 3k miles since buying the car. I was due in March for my next oil change but since COVID19 was springing up in the US around then I decided to hold off. Of course now things have gotten worse and I’m not sure when it will be safe again. I am nervous to leave my house for anything except to go to work so I’d like to hold off on getting an oil change but wanted to hear your opinion if it is safe for my car to do so. Currently I only drive about 1 mile a day, 5 days a week. Thank you!

    1. Hi Morgan,

      Totally understand you may be uncomfortable going out. Have you considered looking for a shop that is offering pick up and delivery service? We are at ours for these type of situations.

      No knowing when this situation changes, but your really going to need your Subaru and you really do not want to neglect it. You could perhaps put it off a little longer as long as the oil is full, but the other aspects of whats done during an oil change will also be missed. Those short trips are hard on your car I will add.

      I can only offer advice about the Subaru and none about when its going to be better or safer for you to go to a shop.

      From the Cars perspective, it probably needs to be done.



  15. I have been told by car repair shops here in Fort Collins and Subaru car salesmen-every 3000 for an oil change-no exceptions. That is what will be done any Subaru that I own.

  16. What are your thoughts on Amsoil oil and filters for a 2010 Forester. I’ve been using their signature line (25k mile) oil for years in cars and trucks, never had a problem. Just purchased the Forester and would like to change over to Amsoil.

    1. Hi Ken,

      Amsoil is a decent tier 2 oil in my opinion or maybe at the bottom of the list of tier 1 oils. Changing the oil when its truly due based on your use its the most important thing.



  17. I daily drive a 2019 wrx (I work as a social worker)…mostly idle and heavy stop and go traffic (central FL traffic), avg 140 miles round trip 5 days a week. I have been changing the oil every 3k miles just because plain logic tells me. I am glad I read this because the Subaru dealer looks at me as I am crazy to come so often for the oil change but hey…I know I was crazy enough to buy a WRX for a work car and I truly enjoy it. I intend to keep it as long as possible…time will tell 🙂

  18. Hello Justin –

    I came across your website via a post on a Subaru owners forum, and was pleasantly surprised to see you take the time to help Subaru owners with questions about their cats – thank you for that!

    Our 2012 Forester 2.5L auto with 90k miles is scheduled to get a new short block under Subaru warranty due to excessive oil consumption.

    May I get your thoughts on what else might be advantageous to get done on the car at this time while they have the engine out? Water pump, timing chain tensioner/guide, any belts/hoses:/gaskets/seals etc?

    The service rep at the dealer suggested PCV valve and spark plugs, for which I would only need to pay for the parts.

    Thanks in advance for any suggestions you are able to offer.

    1. Hello SG,

      Sorry for missing this post until now. It’s been a very hectic month. Anyways if my advice is not to late, I would consider doing the chains, tensioner, guides, pcv and spark plugs for sure. Probably the Rad hoses and the rest is just kind of based on inspection. The biggest Key is them letting the Silicone sealer set up on the timing cove, so stress to them your not in a hurry and just want it done right.

      Hope this helps and sorry if its to late to be of use.


      1. Hi Justin,

        Appreciate the response! Just saw it after dropping my car off earlier today. As it happens, I did request for all items noted by you to be swapped for new parts. But It is great to have expert confirmation that it was the right thing to do. I also requested the serpentine belt and the idler pulleys for that belt to be replaced .

        I initially had the water pump on there as well but decided to leave that out as the Technician that would be working on the car mentioned that they hardly see water pumps on these cars fail before 200k and it is not a very labor intensive job to change it down the road if it does fail (as opposed to spending about $300 on it now). Would you agree?

        Happy Holidays!

      2. Hi Justin,

        Sorry, I cannot find my previous reply to edit, hence this new post. In my previous post, I meant to inquire if you had any advice on proper break-in of the new short block (Forester 2.5 Auto) and when to do the first oil change on it?


  19. Hi Justin,

    I was pleased to stumble upon this tread and see that you have been keeping up with the comments. There is a lot of good info here.

    We purchased a 2009 Forester for our Daughter about a year ago. I did wait nearly a year and 4000 miles before changing the oil (yesterday). On other vehicles I have usually changed the oil every 3500-5000 miles depending on driving conditions or at least annually on our lesser driven vehicles.

    I don’t know what the previous owners used in the Forester. I did pick up the OEM filter and new crush washer torqued to 33 ft-lb. I did switch to a full Syn this time, Valvoline 5W-30 (not high mileage). Did I possibly make a mistake switching to full Syn? If so, should I change to a Syn blend on the next change? With this car, after seeing the size of the filter, I will be changing much closer to the 3K mark, I agree with your comment that even if the oil is good, the filter is so small that it can only handle so much work.

    The Forester has been a great 1st vehicle for our daughter. My wife is on her 2nd OB so we knew that we wanted out daughter in a safe vehicle with fantastic AWD. Now I need to make sure we keep it running. When we purchased it we had the timing belt, water pump, all associated pulleys replaced along with a coolant flush fill and replaced all coolant lines. Knock on wood, no oil or head gasket leaks and I am hoping to keep it that way.

    Thanks in advance for the reply.

    1. Helo Dan,

      If you are going to change the oil every 3-4 months and every 3000 miles I don’t think you need to spend the money on full synthetic. If you were coming to our shop we would be using blend on your car. I wouldn’t say you made a mistake as the oil you are using now is just fine, the mistakes some make, is using Synthetic oil in a Subaru and thinking because the oil company marketing message states 10,000 miles its okay to do that.

      Should be a solid car for your daughter. Keep up on the oil changes and you might very well avoid the Hg thing all together.


  20. Hello Justin’

    I have a brand new Impreza Sport 2.0L and Subaru recommends always to use 0w20 synthetic oil. I am partial to the 5w30 that you recommend being used on many other Subaru models. Is there something different about these FB20D engines that would require 0w20 and that using 5w30 would cause problems with? I think I understand the 0w20 is used for maximum efficiency/mileage but does it really protect this new 2.0L?


    1. Hello David,

      It would be a mistake to use the 5w30 oil

      The engine was in fact designed for the 0w20, I don’t like it either but that just doesn’t change the engineering behind it.



  21. Justin…help!

    My 18yo daughter, under the advice of her 20yo boyfriend just put this oil, Delo 400 SDE SAE 15W-40 API CK-4/SN ISOSYN heavy duty diesel engine oil, in her 2.5L 1998 Subaru Legacy Outback that has 170,000 miles. The boyfriend says “it is really good oil and the best for old Subarus.” I say it is a disaster.

    She drives it to school and around town; 30 minute trips at the longest. Normal use one might say.

    It has a new head gasket and we just had the cam and crank seals replaced. It is in great shape for 21yo. It was leaking a lot of oil before but no smoking from the tail pipe. Too soon to know if it burns any after the seal jobs.

    The previous owner said he only put the conventional recommended oil and at 3k intervals. I told her to keep with what has been working… and then this.

    Is the engine ruined now? Will it do damage? Should I change it immediate or at 3k miles.

    What should I replace it with? Back to the manufacturer recommended oil?

    Thank you so much. I have enjoyed reading your posts and look forward to what advice you may be able to give me as I cool off.


    1. Hello Troy,

      No you should not use 15w40 in any Subaru.

      5W30 for that application and nothing else.

      Might technically get away with it on a 1998 for a bit, but it will decrease fuel economy first, and risk engine damage second.

      I agree its great oil, but just not for that application.


  22. I agree re gasoline, I was only seeking clarity on the electric term. Just as when I say “gasoline” I also mean “diesel,” which is still in wide use in Europe. The distinction matters since one can see forecasters such as yourself, UBS, IEA, etc. all coming up with forecasts, but one is counting BEV (as you are), one is counting “plug-ins” (BEV+PHEV) and one is counting both those and strong hybrids (HEVs). Gets confusing.

  23. What is the recommended oil filter for a 1997 outback?

    My home shop also recommended me to swtich from 5w30 oil to 10w30 for my engine. It’s got about 180k kms on it…. does this sound legit?

    I’ve been using about 500ml/1000km of all highway driving..

    1. Hello Rob,

      We would suggest the Six Star filter here

      switching from 5w to 10w isn’t going to change an oil control ring issue causing oil consumption problems if for example that’s whats the matter so it’s difficult to really answer that question, even if it did help with consumption it would do so at the expense of fuel economy. If I was to suggest anything I would try 5w30 Castrol GTX at your next oil change and see where that takes you.

      Hope that helps
      -Justin Stobb
      All Wheel Drive Auto

  24. Justin,

    I recently purchased a 2007 3.0 L.L. Bean Outback(160,000). I’m curious and weary about what grade of oil to use. The seller, who has owned several subarus , and runs a truck hauling shop swears by Rotella 15w40. My owners manual calls for 5w30. To my knowledge the 15w40 is to combat oil consumption. My worry is the oil could be too thick for the pump, especially in the colder months. I live in Northern Indiana where cold weather is far too common.

    The vehicle is in excellent condition. The previous owner was very knowledgeable and took meticulous care of it. Would you recommend trusting his suggestion of 15w40 for summer months? Also, once the colder months arrive what grade of oil would you suggest i switch to?

    Thank you in Advance,

    1. Hello Thomas,

      5w30 conventional or blend changed every 3000 miles or 3 months regardless of location, using only the Subaru oil filter is what I would suggest. We use 5w30 Synthetic blend on those models, ive currently own a 2018 H6 and that’s what I use.

      Hope that helps


  25. Hello Justin,

    Your website is awesome.

    Just purchased a typically taken care-of 2012 Outback 6-speed manual with 159,000 miles. Based upon everything I can see, touch, and read it seems to have been primarily a long-trip, highway vehicle. Externally the vehicle is well taken care-of – better than average. Internals seem typically maintained. Brake pads, rotors and both rear wheel bearings replaced.

    My intended use is less than 5500 miles per year (< 3 mile trips once or twice per week on average with occasional 50 mile round-trip into the city and very infrequent trips over 75 miles), "urban\city" driving in the very hilly Pittsburgh, PA region. The vehicle will always be parked outdoors (My observation is that an outdoor parked vehicle has a higher rate of problems than a garage kept one.)

    To give you some idea of how little I drive a vehicle, I was driving a Jeep Cherokee 4.7L V8 SHO (13.5 mpg city) and only filling up the tank one time per month on average.

    In a nutshell, severe, very short distance driving in Pittsburgh, PA's wonky hills. Relatively low miles per year.

    I know your guidelines on the oil and coolant changes, but what about other engine fluids such as transmission, rear differential, brake fluid, steering fluid, etc ?

    Any suggestions regarding the clutch and cambelt (timing belt & water pump) ?

    Anything I should be asking about but am missing ?

    I know this car will provide years of dependable service by adhering to the right maintenance plan.


    1. Hello There,

      The 2012 Is generally pretty solid, there were of course the Air bag recalls. The clutch on the 2010-2014 seems to last about like most other Outbacks (which is depending on how its driven) but about 150-200k on average. To the timing belt, if there are no records assume it was not done and have it done, there is nothing worse than finding out the hard way it wasn’t.

      The Differential and transmission fluids should be done about every 30k or every 2-3 years for you.

      I am still suggesting you have a prepurchase inspection performed just to be on the safe side.

      Hope that helps and enjoy the Subaru.


  26. I had planned already to do the 3k mile severe duty oil change cycle on my 18′ wrx. Yeah its probably way overkill, but on a car Im wanting to keep at least 10+ years… why not. Oil is cheap and its one of the few variables to longevity I can actually control.

    In addition the FA is a VERY high compression motor and boosted on top of that.

    My 2010 on the EJ… had intervals at 3750, so… I still dont believe that it can do 6000 reliably given how one typically drives a wrx. Im not saying im redlining it stoplight to stoplight, but the car does like to scoot without much force.

    1. Hey Ryan,

      Great plan, I just picked up a 2018 H6 and will do the first oil change at around 1500 miles, it sure can’t hurt to get the break in oil out. Congrats on the purchase I looked at a 2018 Heritage Blue WRX it looked amazing in that color.


  27. Hello

    I use oil Motul v3000 is the best and full syntetic every 5000km ( Italy ) in my WRX 2004, when the car haved 70000km i put 100 gr bisolfiro molibdeno ( is a lubrification dry aircraft engines ) and my friend certified my engine work fine to 300000Km, now have 96000Km. After many year one engine make minor Km, example engine 20 year make max 25000Km but same engine in 5 year possible make 500000km, becouse ??? after many year the properties metals costruction in the engine collapse.

    Many thanks


    1. Hello Marino,

      I visited Italy last Summer with my family, it was amazing!

      Thanks for the Post


  28. Justin, I am in New Brunswick Canada and this last November I had the first oil change on my 2016 Crosstrek expecting dealer would use Mobil 1 as was done on my previous Subaru Legacy. However, they used a bulk oil and my invoice indicated it to be Mobil Super Synthetic 5000- the dealer indicated there was no difference from Mobile 1 but I am not buying it. I am shortly going to have the 1st change on my 2017 Legacy and am wondering whether to insist on using Mobil 1- am I am being too fussy or is the Mobile Super fine? I drive between 6,000 miles and 10,000 miles and change my oil 3 times a year including after the winter season regardless of the milage. If I go with Mobil 1 should I go with the Extended Performance or Advanced Fuel Economy. Thanks.


    1. Hi Joe,

      Subaru of America requires cars use Indemitsu 0w20 for your Model, no idea what Subaru of Canada is up to there.


  29. Hi Justin,

    I just purchased a 2017 Subaru Impreza 2.0 Base model. The owners manual says to change the 0-w20 Full Synthetic oil every 6,000 miles and no early first oil change. The dealer said to change the oil at 3,000 for the first and then every 6,000. Just wanted your thoughts… I live in the U.P. of Michigan and drive mostly city with a max speed of 60mph on the “highway”. I was also planing on doing all my own oil changes with a Genuine Subaru oil filter and whatever the cheapest full synthetic oil is. Also, what do you think about the “FUMOTO” oil drain valve? Thanks! This is my first Subaru and so far I love it!

    1. Hi Nick,

      So right off the bat I am not a big fan of drain valves, they scare me and I have seen more than a few fail.

      I like the idea of the first oil change at 3000 miles, and from there id say 6000 might be okay but you want to check it lots and often after 3000 miles if not sooner just to check level and condition as you are learning your car and if how you use it means 6000 miles is going to be okay.

      Hope that helps


  30. Hi Justin,

    I just bought a 2017 Subaru Legacy (2.5 Liter model). I spoke to mechanics at 2 Subaru dealerships and they tell me the synthetic 0W-30 should be changed every 6000 miles. I just use my car to drive to and from work every day, nothing crazy.

    What are your thoughts on this? This goes against everything I have ever been taught. I’ve always been told every 3000 miles. Don’t get me wrong, the synthetic oil changes are MUCH more expensive, so I like the thought of the savings but not at the cost of my engine.

    Any advice you can offer would be appreciated.



    1. Hello Paul,

      I would change the oil the first time at 3000 miles or sooner as its really brake in oil.

      Form there I would start checking it for level and condition at around the 2000 mile mark from last oil change, well actually I want you to check the oil level more often then that but for the purpose of trying to tell when its due I want you to start at the 2000 mile mark from last service and really pay attention to it every 500 miles. As soon as its really dark, smelly or 1/2 quart low that is the car telling you it should probably be changed.

      This is changing the oil based on how you actually use the car and not a everyone fits into this mold kind of a thing.

      Hope that helps


  31. Please post pics of the same style engine with oil changed per your recommendations, for objective comparison of sludge etc.

    1. Hi Chris,

      There should be no build up, I have posted plenty of pictures on this site, Facebook, Twitter Instagram etc.

      But I will try to post a picture of a 1st gen 2.5l when I have one apart next.


  32. Thanks Justin! Appreciate your thoughts!

    I have one more question….I noticed oil drips on the floor this morning…I am yet to take it to the shop for a diagnosis. In the meantime, a quick search online about the leak led me to this
    Here they say all Foresters up to 2009 model will need a head gasket replacement at about 80-120K due to faulty head gasket made by Subaru. I was wondering if you had similar thoughts or different and if you could please share them…

    Thanks again for your time! I truly appreciate your feedback!

  33. Hi Justin,

    I have a 2009 Forester 2.5X Premium. I am planning to put Havoline 5w30 conventional oil. What are your thoughts about it? I have 150K miles as we speak…Do you recommend conventional or full synthetic since I have high miles? OR does it matter at all? I live in the midwest (Oklahoma).

    Another question I would like to ask is the coolant. It comes with Subaru long life 10 year or 100K…Do you recommend changing the coolant since I have crossed 100K or wait till 2019 to change it?

    Thank you for your time!

    1. Hi Ken,

      I like 5w30 Synthetic Blend Castrol for that application. But Havoline Conventional should be okay as well, just don’t try and go 7000 miles, it wont work long term.

      The coolant should be tested every year after 3 years for the proper PH levels and changed when out of range. But if the car has over 100k it should have been done, its whichever occurs first 10 years 100k.

      Hope that helps


  34. Agree fully with the 5000 km interval. Buddy of mine who is somewhat of a Subaru guru did head gaskets on my 2004 at 200,000 km and made me promise to change oil every 5000 km. He currently has a 2007 Impreza in his shop for a head gasket job with only 100,000 km on it. He loves the cars.
    I do the same interval change on my old type 1 Beetle which was always the recommended interval. Cheap insurance at $30
    Chris JM

  35. Hie Justin
    Once again. i cant find oil for my Subaru Legacy B4 2004 Model GT 2.0. you advised me to look for 5w 30 Synthetic blend, but l cant find it. Instead l can find 5w 40. can it be a substitute, or what can be a substitute.
    The second question is, can you help me with the reference of rear wheel bearings, they are making noise as the car gains speed also the left wheel is kind of binding and heating a lot, just for a small distance. thanks a lot for the support

  36. Hi Justin, Enjoying reading your information. I have a 2008 impreza 5MT which was completely rebuilt. Unfortunately, it seems to be smoking on startup. I am using 5w30 full synthetic and 3000mile changes but I seem to need to add 1 quart per 500miles, any suggestions on how to proceed. I have advised my mechanic but I am unsure what the best next step is.

    1. Hello Ray,

      Smoking on start up is most likely worn valve guides and or seals, there are other possibilities, but that’s the typical kind of a thing, which is unfortunate if it was just rebuilt? There really is no testing that can be done short of removing the heads and having a qualified machinist have a look.

      Hope that helps and sorry about the news


  37. Thanks a lot Mr Justin, l will try to work on your recommendations. Unfortunately l am in Mozambique and the state of our roads is very bad, Just bought the wrong car. Thanks a lot once again

  38. Hello Justin, thanks for the great support you give us. Keep it up.
    l have 2 questions. 1. l am running a Subaru Legacy B4 2004 model, 2.0 GT. what kind of oil should l use for my car. l drive for short distances every day home to work and back about 14km a day.
    2. About 8km l do every day, its a dust road, it raises a lot of dust and during rainy season , a lot of mud. is that safe for my car. what other components should l change Regularly? l appreciate your help

    1. Hello Watson,

      I would use 5w30 Synthetic blend. As far as what else, based on what you have said I would keep a careful eye on the air filter, and cleaning the Mass Air Alow Sensor with an approved cleaner is also probably wise.

      With the Mud Id try and wash it out of the undercarriage and wheels as it can collect in the wheel wells, wheels, brakes etc and cause problems.

      Hope that helps and I wish your car was available here in the US:)


  39. Hey Justin, just a quick question. I have a 95 impreza (gc8) 2 door 2.2l.(ej22) its leaking from the infamous rear main seal. I dont really have money or time right now to repair it the right way. Whats you take on “Bars Rear main stop leak” additive. According to the reaserch ive done people swear by that stuff and seams to work for what i need it to do. The car is my daily/rallyx project. I just need the leak to slow down or stop long enough to replace the engine and tranny in the future.


    1. I am sorry but there is just nothing in a bottle that you should ever put in.

      You will over time cost your self way more then you will.


  40. Hi Justin,

    I recently purchased a 2005 Outback XT Limited 5MT. I really like the space of the outback combined with a turbo for mountain driving. I’m just making the switch to full synthetic from conventional oil. I’m on a 3000 mile interval between oil changes.

    My question is about which oil to use. I really like Mobil 1 so I’m planning to use it but the outback just recently turned over 75,000 miles which is the point that Mobil 1 high mileage is recommended. The other reason I’m thinking of using high mileage is to combat a very small oil leak. Am I losing any protection/Etc by using the high mileage right at 75,000? For more background I’m also using OEM oil filters.

    Thanks in advance for your reply. Also, thanks for writing these articles/white papers, they are very informative and interesting. I actually had the banjo bolt replaced when I purchased the outback (63,000 miles) because of your article.

    1. Hey Mark,

      Thanks for the Feedback.

      So at the shop we use a high mileage oil for anything not requiring full synthetic, high mileage oil can vary by the maker but is generally going to be a blend of conventional and synthetic. I see no reason why you should not use it.

      Hope that helps and good job on the maintenance!


  41. Hi Mr. Stobb
    I purchased new a 2011 Forester. I live up in Toronto Canada. Since the purchase I’ve put on about 32000km, maybe 20000 miles. I drive like an old lady, speed limit, no hard braking, maybe drive the highways 5 times a year to go to a beach somewhere. I have been following the Subaru maintenance schedule to a tee but for someone who only drives the car once, twice a week for maybe 20 miles round trip is it a good idea to change the oil every 6 months? Do you recommend sticking with the dealership or would you think going to auto center which is much cheaper a better idea?
    My second question, sorry, if you don’t mind, is how long should brake pads last? The rear brake pads where replaced last Spring with only 30000 km use. And now they are informing me that my tires are worn out and should be replaced after 4 years. The thing is I have winter tires with steel rims put on in October and removed in March so the regular All Seasons that came with the car are in storage six months out of the year. Is this normal?
    I ask because I drove a 67 Pontiac Laurentian until 2011, rear snows put on in the winter, oil change once a year, replaced the pads around 1995. Just a silly comparison. Any answer to the above questions is greatly appreciated, thanks.

    1. Hello Joe,

      So I just cant state enough that I don’t like the idea of the Subaru Dealer for service, all they see is $ when they look at you.

      I cant really fathom a scenario where the rear brakes are worn out before the fronts, and before 60k.

      As far as the tires, I don’t know which ones they are and its possible they could be worn if they were not rotated properly, you haven’t mentioned if they were rotated at least twice a year..

      As far as how often on the oil changes?

      It’s not a waste of money to change the oil 4 times a year, but I can see with limited use why thats tough to follow. The problem is that sitting is tough on a car, tire rot, internal parts of the engine loose lubrication as the oil drains away from sitting, I can go on. Think of it like this, the longer you sit the harder it is to get going and if you were to go from sitting for hours to immediately running you might have an injury. While a car is a piece of equipment, the same basic principles apply, the longer it sits, the tougher it is on it to get going.

      Lastly, yes please look for a good independent shop, not to save money but to get better service.


  42. Hi Justin,
    I have a Legacy 2008 wagon. A mechanic put Total Rubia TIR 7400 15W40 which is a heavy duty synthetic oil for diesel engines. My car has a petrol engine. Is this ok or I should be worried?

    1. Hello Paul,

      I would ask your guy to drain it out, replace the filter and put 5w30 back in, I am not sure where you live but if it gets cold there before it’s taken care of engine damage could occur. Also the Variable valve train wasn’t designed for that grade of oil and you may start setting check engine lights.

      Hope that helps


  43. I appreciate your website Justin. I came here because I am confused about what kind of oil to put in my 08 Forester that I bought at 13,000 miles. It has 46,000 miles on it now. The manual states to use 30W oil, which I recently heard isn’t made anymore. I think it has been running with 5-30W instead. Then I went to a new mechanic who talked me into synthetic. But I noticed on the synthetic, smoke would sometimes come out of the exhaust pipe, which concerned me. Then one day, before the 3000 miles were up, I checked the oil level gauge, and the level was so low I panicked. I added oil but had never had this happen with regular oil. So I went to a different shop and back to regular oil. The Forester seemed fine. Now I’m taking it in for spark plugs, etc to that mechanic who is pressuring me to go back to synthetic again. He says its better for the engine. But I’ve been reading a lot and it sounds like synthetic oil and Subaru seals may not be compatible, which could be why it smoked while running on synthetic? But then I wondered, was the synthetic cleaning out the “sludge” I’ve read about? This mechanic told me if it smokes with synthetic the car could have head gasket leaks and to use Blue Devil Seal Softener. The engine only has 46,000 miles on it and I’ve taken care of it that I don’t want to consider it has a problem like that already. It doesn’t burn oil with regular oil, only with synthetic. He told me that would clear up after a couple oil changes. Umm I don’t know what to do. What would you do? thanks so much for any advice to un-confuse me.

    1. Hi Vickey,

      Fire the “mechanic” who told you to use any blue devil product. Look for a Technician instead.

      The car requires 5W30 oil, and synthetic really shouldn’t be used.

      Stick with basic oil, or blend. I suggest 5W30 Castrol GTX or high mileage.

      Synthetic oil isn’t a detergent oil so its not going to clean anything, it burns away quicker most likely as a result of the additive package in the type of oil being used.


  44. 100% agree with this article. I bought a 2000 Subaru Outback brand new and changed the oil every 3000 miles like clock work. I was NOT brand specific on the oil but did keep it changed. That car ran for 306,000 miles. One time both head gaskets were replaced, normal tune ups and the normal T-Belt changes were the only time the engine was touched. The original trans lasted that long as well. The car would have gone longer had the T-Belt not broke. 3000 Mile oil changes are the way to go.

  45. Hi
    I have a 2014 Impreza and my CHECK ENGINE light has been coming on and off for the last 6 weeks. My local dealer couldn’t find the problem but suggested an oil change. When the light continued to come on and off after the oil change he suggested cleaning the valves. I went to another Subaru mechanic this week and he checked the valves – they were clean – but the light was still on. Subaru told him to chang one valve and when the CHECK ENGINE light continued to come on he changed a second valve. My question is when my car was hooked up to the computer in the very first place why wasn’t more accurate information transmitted? Why was it a trial and error situation on the part of both mechanics? And is it likely that the CHECK ENGINE light will go on again or does it sound as if the problem is now permanently fixed? Many thanks

    1. Hi Linda,

      Whats the code they are telling you is setting?

      the 2014 is under warranty, if you have trouble getting a real answer from your dealer call 1800 Subaru 3


  46. Hi Justin,

    Really appreciate all your expertise on subarus and sharing your knowledge.

    I just had timing belt and components, mls head gasket, valve cover gaskets replaced on my 2007 subaru impreza 2.5i with 166 000 km. I have been using Amsoil filters and Amsoil sythetics (5W30 and eventally 5W40 Euro) and most recently Shell Rotella T6; not much difference in terms of oil consumption. I have been adding anywhere from 0.5-1 quart per every 1000km on 10000 km oil change intervals with “supported evidence from oil anaylysis”

    After reading your article, I realize that switching to GTX may be the best option with more frequent oil and filter changes; every 5000km? I do mostly 80% highway and average 20 000 km/annually.

    I was encouraged and have read that an oil change after such major work, as mentioned, should be done within the first 100km after, but my mechanic suggested after about a week or none at all – request some suggestions. Also, would it also be fine to go from synthetic to the GTX (i belieive it is a semi synthetic high mileage)?



    1. Hello Mike,

      For your car we would suggest Castrol GTX, or high mileage. Either one will be a semi synthetic or “blend” type oil. I would use 5w30 and really consider oil changes every 3000 to 4000 miles depending on how you drive it.


      1. Thanks for the reply, Justin.

        Is it necessary to have an imminent oil change after having head gasket replaced and machined?

        1. I would check the oil after 500 miles, again at 1000 then every 1000 miles (provided its not using oil) and change it at the 3000 mile mark.


  47. Hi Justin,

    After about a year or researching Forester models, I finally got a nice little 2005 XS with 62K miles from the original owner. I took it to an independent Subaru mechanic for the 60K service (incl. oil and coolant change), and when I asked what kind of oil he said 5w30, but emphatically added it should be *non-synthetic.” Is this simply because of the relatively low mileage or because that’s what they’d just put in it? Also, what kind of coolant should be used on this car?

    1. The car does not require Synthetic, if you want to spend the extra money on it that’s really up to you, but it wont really change the oil change interval.


  48. Very informative. From my experience with marine machinery, I have learned that lubricating oil does not wear out, but it does get contaminated. To eliminate problems caused by con-
    terminated oil, it needs to be cleaned continuously. Ideally, oil filters for Subaru engines would be much larger than what comes with the car. The only alternative is more frequent oil+filter changes. My 2007 Legacy GT Limited wagon came with 10W-30 Castrol GTX in the sump, which I have continued to use. Even though the Owner’s Manual says otherwise, I continue to wonder about using synthetic/synthetic-blend oil. At 90,000 miles, I do not have any leaks, and as far as I can determine “0” oil use between 3,000 mile-interval oil+filter changes. Can you suggest an oil filter larger than the OEM? Would there be any advantages to changing type and weight of lube oil at this point?

    1. There really isn’t room for a larger oil filter based on the location of the exhaust.


  49. Hi Justin.
    I enjoy reading your articles and it sounds, that you really know Subaru’s inside and out.
    I would like to ask you a question about high mileage oils.
    I just bought a 03 Forester with 120 000 miles on the clock.
    Considering the Subaru head gasket issues, would it be a good idea to use high mile oil, since most of the brands say that their product will “condition and swell the old dried up seals”?
    On paper it sounds like a good idea, but I would really like to know your opinion on this.
    Also, would you be able to recommend a good brand along with the preferred viscosity number?
    Thank you in advance for any input.

    1. Hi Dave,

      The preferred oil for that model is 5w30 Castol Synthetic blend, also called high mileage or GTX.

      Should be in the green Bottle.


      1. Thank you Justin.
        Being that the summers are usually pretty hot where I live (Southwestern Ontario), do you think it might be a good idea to run the 5W-30 in the winter only and switch to 10W-30 in the summer?
        My concern is, that the oil might get too thin and runny with the heat, thus inviting leaks out of places, that normally wouldn’t…..or would you recommend the 5W-30 all year round, regardless of the climat conditions?

        Also, would you be able to give me your personal opinion on Lucas heavy duty oil stabilizer?
        That one claims to be compatible with any oil and also claims to be able to form some sort of a protective barrier, which is supposed to be superior to the one that the engine oil makes….
        Thanx again

        1. Hi Dave,

          I am not sure which era Subaru you have so I cant 100% answer the oil question.

          As far as the oil additive, I don’t really have an strong opinion. I personally don’t really use anything, but its kind of a each to their own kind of a thing.


  50. Hi Justin!
    I am so thankful for this post! We just bought a 2014 Subaru Impreza. We are new to the Subaru world! For a 2014, would you recommend oil changes at 3,000 miles (with it being a new model)? We live in AZ, and drive the vehicle about 10 miles/day. Do you have any recommendations about this vehicle/maintenance?

    Thank you for your posts! They are awesome!

    1. Hello Ashley,

      Thanks for the post, you may be okay at a 5,000 interval with the 2014. I would check the oil every few fill ups and monitor oil use and the condition of the oil based on how you are using it. During the summer months it may use a little more oil due to the heat and the Ac use.

      Hope that helps


  51. Hi Justin,
    Thanks for post. I wish I lived closer to your shop but, alas, I live in Portland.

    I have a 2005 STI with 160k miles and am experiencing some oil consumption. I change my oil every 3400 miles.

    I know that my driver side exhaust cam seal is leaking from inspection. Before I change this seal which doesn’t seem to be coating my timing belt, I thought it might be a good idea to inspect and change the PCV and hoses. In your experience, does this seem like a correct approach to you? Have you had this issue before with PCVs on this motor? As far as I know, the PCV has never been changed. Everything else has been maintained to Subaru’s recommendations (t-belt, water pump, and idlers) Is there anything else you could recommend checking to see if I am not dealing with a bad seal but an over pressurized crankcase due to bad ventilation?


    1. Hi Scott,

      Id start with an inspection of the PCV and replace components as needed, Oil consumption on your model could be the turbo so I would have a look at that as well. Unless the cam seal leak is large I might hold off until I had a handle on the Consumption, as if you replace the seal only to figure out the oil rings are worn it was a lot of work for not.


  52. hi, I was going to change ignition wires and plugs when I discovered oil filled the plug cavities when I pulled off the old wires… Would this be a gasket issue? Like remove the valve cover, replace the top gasket, plus round gaskets down some rod by the plugs? Guy at a parts store said there’s a kit… that may remedy the oil leaking. Would appreciate your input. 2000 Subaru Outback with about 150K miles. Runs good.

  53. I think Justin is right. I have always changed my oil and filter at around 3,000 miles. My 1998 2.5L Outback has 216,000 miles on it and does not use oil between changes, and is driven about 60/40 city/highway. The only engine work I have ever done was installing All Wheel Drive’s updated head gaskets at 202,000. When I removed the heads there was virtually no sludge in them. I dropped the heads at the machine shop in the a.m. and gave them carte blanche to do whatever was needed, and returned home from work in the p.m. to a phone message saying to come get them. The machinist said they needed zero work on the valves, guides, and cam journals. I had them lightly surfaced and put them back on.

  54. Hey Justin,
    Got my first subaru- a used 2005 outback 3R in January. Going for first oil change as i write this. I had been reading your articles for the past 6 months and everything you wrote had positively influenced my selecting and buying subaru and how i am going to keep it. Just wanted to say thanks for all the advice you put out there.
    Keep the good work going..
    How about opening shop in canada? Lots of Subarus out here I think..

    1. Hello Nate,

      I love Canada, some of the most beautiful Country I have ever seen and as I am an Outdoor enthusiast so we would get along just fine. However it looks like opening a shop up there would have a lot of challenges from what I have heard from discussions with shop owners. We have had a few come down here from BC for larger repairs.

      Congrats on the Subaru I hope it gives you years of good service.


  55. Man why cant people just allow the wheel to be round! A bit late to point out but even with oil “analizing” it doesnt prove that the filter isnt going into bypass or will soon. March 1st is just around the corner so its a good time to start a 3 month oil routine. Ever thought about getting a shop down in San Diego?

    1. Here Here. I live in Redding, CA and there is not a single independent Subaru specialty shop within driving distance, despite the streets crowded with them. I wrecked my Outback and couldn’t afford another one this go around, but I will have one again. Thanks for the good info Justin. Half of everything I learned what to do on a Subaru started by reading your blog and follwing your website.

  56. Hi Justin – I’m a big fan of your website and I’ve gained a lot of insight from reading your articles and posts. In fact, I bought a 2001 Subaru Impreza (EJ22) for my son and we found out later that one of the head gaskets was bad. We pulled the engine and did the work ourselves and it’s running fine now, I believe in large part to the information I gained from your website.

    I recently purchased a 2009 Impreza Outback Sport with 69K miles on it. I’m working out of state during the week and driving back on the weekends to see my family – it’s a 1000 mile round trip (all expressway), so I think it puts me into a “normal” maintenance schedule. I purchased Mobil 1 oil with the long life filter when I changed the oil last time with the idea that it would give me a 15,000 mile interval between changes.

    Based on what I’ve read in your article, it seems that maybe I’m expecting too much from my oil? Is my driving situation unique enough to consider the long life that is advertised for the full synthetic oil? Ultimately, I’m trying to do what’s best for the car – I take a lot of pride in maintaining my vehicles. I’d prefer not to have to change the oil every 3 weeks, but if that’s what is best, then I will.

    Keep the good information coming!

    1. Ho Dave,

      I think that based on the drive you are ok going out past the 3000 mile mark up to 5000 miles most likely, and perhaps even little higher. What I do want you to do is monitor Consumption after 2500 miles, and use that info as a tool as to when you should consider changing it.

      The more it burns, the more its diluted, the more its diluted the more its a solvent, the more its a solvent the more particles end up in the filter.

      Hope that helps.


  57. So much bad information and assumptions gathered together in a sigle page is really impressive. Having your oil analyzed is the only way to really know what is going on. When you get your oil analyzed they will included the amount of contamination including how much the gasoline has diluted and broken down the oil and particulates which would indicate weather or not your oil filter is still working. Every mechanic has opinions. 2 year trade schools do not make one a biochemical engineer no matter what your mechanic tells you. Change your oil and filter as often as makes you feel good. If you go longer than recommended get your oil analyzed. Opinions are like a__ holes, everone has one. You dont need to listen to mine either. :0)

    1. “So much bad information and assumptions gathered together in a sigle page is really impressive”

      I sure hope you feel better after saying that?

      Do you really contend that spending $30.00 for an oil analysis, then spend money to change the oil is worthwhile? Do you understand the reasoning behind an analysis? Probably not, I will let you in on a secret.

      Oil Analysis, was a test intended to help fleet owners better know the condition of the internal components of the internal combustion engine, mainly large diesels and mostly to know when it was time to do a rebuild, so it could be planned for and downtime known about. But in a Capitalist Society like the great one we live in, you can’t stop there, you need to sell your idea to the world to expand the bank account, this is where the DIY crowd fits in.

      Should this be part of your maintenance plan? If you believe so by all means, but what would the average driver gain from this!

      Back in the “Ole Days” there were these guys called “carpetbaggers” that sold “snake oil” to folks of all sorts of intelligence levels, your rogue scholars all the way down to just plain stupid. It was never about the product, it was in fact one of the first examples of successful marketing of a products additional uses above and beyond its original intent.

      Next I find it incredibly rude, short sighted and ignorant that you would try to belittle someone who as at a minimum obtained some education in the chosen field they have pursued. I am not even talking about myself, but those in my industry that are constantly at odds with those that mock the profession as somehow lesser than their own.

      A life time as a “Biochemical Engineer” does not make you qualified to be an expert on the internal combustion engine, regardless of what the voices in your head may be telling you.

      Yes, I believe that someone who has studied and then mastered with experience the subject of Automotive Technology has an advantage over someone who studied say, Quantum Physics for 8 years when it comes to the true design and function of a dedicated system within an automobile. But you won’t find too many Automotive Technicians that think because they reflashed an ECM yesterday they are now masters of the universe, we’ll leave that up to the “Smart Folk”

      You may somehow believe your intellect superior, and you are most welcome to that opinion, what I try to point out is there is a reason to go to school, training or an apprenticeship program before becoming a Technician, I work in this industry I have seen good techs and bad, there has always been one constant, the ones that let in a little education around the factual aspects of the combustion engine, tend not to skip the most basic of details when suggesting maintenance.

      Its the ones that formed their own opinions based on “internet knowledge” often found on forums, typed in stupidity by the very “engineer types” that believe their singular wit superior to the rest of the human race, and seem to have an expert opinion on everything from Apples to Zebras.

      Lastly, checking and changing oil is as basic as it gets, I don’t believe in trying to over complicate it for the average family of four trying to get through today’s overworked, hussle and bustle by suggesting they send the oil out to be “anal” yzed.

      The round tire still rolls the best, checking your oil, adding when its low, and changing it when its due is still the best way to avoid engine failure, even if there are those that would like to reinvent the wheel.

      The point of the article is to help some Subaru owners avoid engine failure by not understanding what they own and how to maintain it based on their use.

      What I deal with on an almost daily basis is an owner that does not understand the very basics of car ownership either from lack of understanding or lack of desire to understand, the last thing I am going to do is over complicate it for them.


      1. Hi Justin,
        I bought my first wrx 2016. I changed my first oil at 3000 second at 5700. its almost 9000 now. Should i change third one? I use amsoil oil ! what do you think of amsoil?

        1. Hello Asad,

          I would change the oil on a Turbo charged Subaru every 3 months or 3000 miles regardless of what oil you use.

          Hope that helps


          1. Thanks so much for the great information Justin! I’d rather spend my money on an oil change than on a new engine.

  58. Justin, great advice. I do about 4000 miles a year (retired) should I change the oil more frequently – every 6 mths – or is once a year enough? thanks

  59. Hi I just bought a 1997 Outback and they have had synthetic blend oil in it. I am thinking of switching back to regular oil because it is cheaper. Is that ok for the car? Thanks.

    1. I have the opposite question. My 1998 2.5L Legacy Outback just got the oil changed. I told the shop to use conventional. The receipt says synthetic blend. I always use conventional 5W30.

      Will this shock to the system cause trouble? Cause leaks?

      Thank you very much,

  60. Hi, Justin. Got an ’03 Outback with 106K. So far, so good. Love the car. I am the second owner and for the past 15,000 I have been running Mobil 1 synthetic with non OEM oil filters (Bosh, Mobil 1, Purolator) I live in Ohio and the oil change interval I set is 5000K. After reading your posts I am considering switching to 3000K oil changes. I am also thinking of switching back to conventional oil to offset some of the cost. I heard somewhere that once you go “synthetic” you should not go back to dino juice…. Thoughts???

    1. We use 5w30 Synthetic blend oil for 90% of our customers and Full synthetic for the rest.

      Oil is one of those things that everyone has an opinion about, I like blend oil done every 3000 to 4000 miles. Followed by Synthetic and the same interval, the Subaru oil filter is just to small to let it stay on for much longer than that. Some people will just change the filter, but I am not a huge fan of that either. Its a piece of machinery and the less friction the rotating mass incurs the better off it will be, I use that one rule and that one rule only. Everything else gets clouded in the conversation about oil and intervals. There for example are many on the WRX forums who hate Mobil 1 and feel it caused rod bearing failure in their engine. I personally like Mobil one but not as much as I like Motul and Enos, which is why our shop stocks the later 2 choices. Does that mean Mobil one shouldn’t be used? This is what I mean by cloudy.



  61. Changing the oil doesn’t prevent gasket leaks. Nor does it prevent electrical failures or problems with the fuel system, etc., etc. My 30+ years experience says getting a good car is a roll of the dice. I’ve bought second cars of the same model because the first car was great; only to have the second car be the worst car I’ve ever owned. Changing the oil more frequently than twice a year just wastes oil no matter how you drive.

    1. I am sorry but your thinking about this in the wrong frame of mind. You also wont like my response to your post but its intended to educate not offend.

      You will notice the title is “Why Changing Your Oil In Your Subaru Every 3000 Miles Is A Must For Most Drivers”

      The logic behind comments like this is exactly why the Auto Repair industry is a multi billion dollar industry. You can literally clean an oil slick up with a small amount of fuel, but somehow the concept of this also happening in your engine is lost to any that didn’t actually attend some sort of formal training like a 2 year trade school.

      A contributing factor to gasket and seal failure on a Subaru due to the design of the H or boxer engine is contaminated fluids. A real lack of understanding about how well or rather how poorly the combustion chamber is sealed away from the crankcase and what happens when fuel is mixed with oil and the diluted oil is circulated around the engine is common place through out the industry.

      Poor some gas on a rubber seal or better yet dip a rubber seal in a container of oil and gas mixed and tell me what happens over time.

      Fuel is a solvent that deteriorates seals, corrosion from old coolant will cause gasket, seal and block damage.

      I truly attempt to educate about why oil is the cheapest insurance you will ever buy. Old oil affects seals and gaskets, friction thus engine wear, fuel economy and the performance of the entire drive train. It is one of the first things you learn if you receive formal education rather than just on the job experience.

      My industry is plagued with individuals that understand how to take it apart and put it back together but no real understanding about the separation of oil vapor form oil liquid at a specific temperature and how this really doesn’t occur for the majority of us stuck in the “Rat race” during our commute and as such oil needs to be checked and changed as needed based on how the vehicle is driven, some fall into every 3000 miles some every 7000 miles but assuming your the 7k type, or someone else reading a post does and having a engine fail or a gasket leak earlier than the guy who changes it every 3k is how your ownership costs go up. Its called counting your nickels only to have 50 dollar bills fly a way.

      The parts in a car are all made the same way, assembled mostly by machine and have exacting standards, the only variable is the use of the vehicle after purchase. There are some cars that have defective components but that is a whole different conversation.

      When I plead with Owners across the country to change their oil, check there oil and take responsibility for all of the aspects of car ownership its so there are no surprises, no major mechanical failures, no financial hardships.

      Planning on changing your oil twice a year and driving the vehicle in a way that dictates more maintenance than that is just a repair waiting to happen, either to you or worse the next owner.


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