Hi All,

Our Outback 3.6R Limited, which has 167,800 miles on it, gets Mobile 1 High Mileage full synthetic oil and a Subaru filter - and I do the oil changes myself. I was wondering how many miles to go between oil changes?  Thoughts?  Thank you, Craig

Do some oil analysis and find out what THAT ENGINE wants. NOT what a manual says, NOT what anyone else *thinks* you should do. Get oil analysis and use SCIENCE to determine a proper interval. 

GD

GD, perhaps you can tell me where one would get an oil lab report? Keep in mind too that this is a family car, not a high performance race car. While I appreciate your sincere suggestion, it seems a little extreme, particularly if such an analysis is expensive or not commonly available. Thanks C

an oil analysis from Blackstone or Polaris labs, etc. can tell you how far you can stretch the oil change (and also offer you a heads-up on 3-4 kinds of 'trouble'.)

Blackstone is quite popular. To read more about oil than you ever wanted to, you could also visit www.bobistheoilguy.com

 

Otherwise, it's just a guess. personally, I think synthetic is good for 5K miles or 1 year, w'ever comes first. But, only an analysis could give you actual data. Your car, climate, and driving might be good for 8500 miles??? who knows?

 

certainly extreme use like racing, towing, offroad, etc. could change that.

Edited January 26, 20215 yr by 1 Lucky Texan

57 minutes ago, craigmcd said:

GD, perhaps you can tell me where one would get an oil lab report? Keep in mind too that this is a family car, not a high performance race car. While I appreciate your sincere suggestion, it seems a little extreme, particularly if such an analysis is expensive or not commonly available. Thanks C

Blackstone is a common provider. Go to their website, they make it easy.  

Car101.com is a great unofficial subaru reference point for maintenance intervals/oil changes and more by a Subaru dealer staff member. 

I like 5,000 miles for convenience - it’s easy to remember - change it on every 5k multiple - 160k, 165k, 170k.  And it’ll be conservative enough to be under any lab tests for synthetic and is generally in reasonable (IMO) ballpark of factory recommendations. 

The only extreme here is the original question. Oil change intervals are common knowledge, documented in the owners manual of the vehicle, and infinitely available free online. Opinions on oil changes are usually terrible or not well versed, even from car people. I don’t think I’ve ever heard well versed oil comments from someone in person, ever.  It’s amazing how oil discussions just break out the tinfoil hats and dunce caps even from professionals.  Use the owners manual or get it tested.

A question about something this easy and ubiquitous suggests maybe there’s a specific reason for the question?

In which case a lab test is a really good, if not the only, answer. most other forums would give an endless supply of anecdotal opinions if you’re just looking for chatty banter over dinner kind of stuff. 

 

Amsoil, Blackstone, etc. Many options out there. In general a single test is about $20. If you use quality oil, which is expensive, you can absolutely pay for the analysis by not changing it more often than needed. And I'm sure you can guess at the cost of a replacement engine. 

All branches of the military, virtually all government agencies, and most corporate fleets do regular analysis. Why? Because it saves money and effort. Do you hate money and love effort? Then by all means just wing it. 

No one here can answer your question. We aren't you, and your car isn't in our driveway. Your engine is subject to ENVIRONMENTAL CONDITIONS which are unknown to us and probably to you as well. Without that data the best anyone here can do is a blindfolded dart throw.

As far as expensive racing engines go - we don't do analysis on those. They get what's called the "maintenance rebuild" when the power drops, they start using fluids, or they go boom. They are purposefully loose, burn oil as a necessity, and run REALLY EXPENSIVE oil that doesn't last for $hit in terms of TBN and detergents, etc so it gets changed every event regardless of condition. Oil is WAY cheaper than a race engine so that stuff gets dumped long before it is ever "worn out". 

GD

Edited January 26, 20215 yr by GeneralDisorder

@GD. Just became the owner of a 2019 OB 2.5 that uses synthetic. What brand do you recommend?

In the past, with my porous 05, I used the cheapest Dino I could find as it spent little time in the engine before fouling my driveway and undercoating the engine bay.

As an aside, as I near 70 years on my personal odometer, I am thrilled that the oil filter now sits atop the engine for easy access. If only the drain plug was relocated to the front bumper...

4 hours ago, brus brother said:

@GD. Just became the owner of a 2019 OB 2.5 that uses synthetic. What brand do you recommend?

In the past, with my porous 05, I used the cheapest Dino I could find as it spent little time in the engine before fouling my driveway and undercoating the engine bay.

As an aside, as I near 70 years on my personal odometer, I am thrilled that the oil filter now sits atop the engine for easy access. If only the drain plug was relocated to the front bumper...

He uses Amsoil. And says run from the 0W oil as your warranty allows it.

You can get a fluid extracting pump made to extract oil from the top maybe - from the dipstick or oil fill hole. Don’t know if they work on Subaru’s but I use one on CVTs and know people use them on cars low to the ground.  Battery operated, very slick. 

Edited January 26, 20215 yr by idosubaru

Thanks again for the replies. I will look into getting an analysis. I got a soil analysis for my yard last year, might as well get one for the car.

My main motivation in the original question is simply to have the engine last as long as possible. We tend to keep cars many years (I have owned my Chevy van for 21 years), and want to keep big expensive repairs to a minimum.

Have a great week. C

6 hours ago, craigmcd said:

Thanks again for the replies. I will look into getting an analysis. I got a soil analysis for my yard last year, might as well get one for the car.

My main motivation in the original question is simply to have the engine last as long as possible. We tend to keep cars many years (I have owned my Chevy van for 21 years), and want to keep big expensive repairs to a minimum.

Have a great week. C

Oil choices will do very little to prevent expensive repairs on a lightly used daily driver.  The best thing you can do is to check the oil and coolant level often. Every fill up, schedule it monthly, etc.  Low oil is the chief oil issue by many orders of magnitude.