I has wagons.
There isn't such a thing as "best" as long as it meets the specs listed in your owner's manual.
Oil / filters are cheap.At 3k you are wasting oil and money. The oil is barely being used at that interval.
The days of 3k are long gone
While it's true that "penny pinching" in the sense of trying to save money by buying inadequate lubricants (or inadequate anything) is a fool's game, this is a completely preposterous argument in this context, because so long as the lubricants used meet Subaru recommended specs, they are not in the least inadequate.It's Not worth the risk of penny pinching on this .
That's a fair point although in my view the discussion can move beyond the standard recommendation.While it's true that "penny pinching" in the sense of trying to save money by buying inadequate lubricants (or inadequate anything) is a fool's game, this is a completely preposterous argument in this context, because so long as the lubricants used meet Subaru recommended specs, they are not in the least inadequate.
There is not one shred of empirically verifiable evidence to suggest that using oils graded in accordance with the recommendations in the Subaru manual, and changing them at the recommended intervals, will reduce engine longevity or performance by one single minute.
Putting this another way, there is no verifiable evidence of longer engine life from using expensive boutique oils or shorter OCI's than from using whatever is on sale—at the recommended OCI—so long as it meets the manufacturer's specs.
The "penny pinching" argument is simply a marketing ploy designed to make you feel like you're making a terrible mistake by shopping around for the least expensive alternative.
This is marketing 101.
First create anxiety by suggesting you're "doing it wrong" and taking a huge risk by "being a cheapskate", then offer your expensive product as the solution. People fall for it every day, then get irritated when it's pointed out to them.
That's all fair enough, but so what?That's a fair point although in my view the discussion can move beyond the standard recommendation.
What the OM and the SAE standards do not and cannot predict is environment. All the OM can do is give you their best view on normal and severe service. Clearly and without much consternation, the mere fact that SOA, and all other manufacturers too, gives you a recommended severe interval tells you that the normal interval isn't ideal because their recommended oil will break down or be unsuitable.
This is exactly why the OM goes further and says that for your environment you may need to change your viscosity. SOA just makes an educated guess on how and where most people will use the car but they also give themselves an out too. Smart by SOA but it still tells you that even they don't stand by one viscosity for a set length for all conditions.
One important thing to consider is that all SN 5w-30 oils are nearly the same. Nothing more than variations on a baseline standard and for the most part, one is as good as another and therein lies the problem.
Look at any of the VOAs on BITOG and then UOAs for the same oil. They all seems to lose their cSt values but also stay in grade although in the low end. Just a fact of life with oil.
If you run for distance where the oil gets up to temp and stays there then you're doing well but for me, I make one way trips of less than 3 miles on some days and the oil never gets up to temp aka I'm running rich which is the number one reason for diluted oil. The dilution thins it out and lowers the cSt value.
By running, in my case Redline 5w-30, a different oil than a garden variety SN oil, I get a much higher cSt so the dilution isn't as much of a concern. I think the highest cSt oil available at Wally World has a value of 11.1 and many oils are much less. The Redline has a value of nearly 12 and Castrol Euro 0w-30 has a value of around 12.2. These are all within grade for a 30w oil but at the upper end while still meeting the grade requirements. If M1 or Pennzoil offered a 12 cSt with a HTHS of 3+, I'd be tickled to death but it won't happen because thin oils help meet CAFE mileage standards.
So thick vs thin does have relevance to the analysis and SOA intimates that it does, depending on use.