Subaru’s Contradictory Oil Recommendation.....

Originally Posted by Brigadier
You want confusing oil requirements? Buy a Hyundai....

HaHa - You sure are right about that !
 
I love this statement: "Changing the engine oil and oil filter should be performed by a well-trained expert."

I guess that means no DIY and especially no Jiffy Lube.
 
Hah. I'm sure plenty of people on the board are waaay more trained than most dealer oil change techs. I know at my brother's work anything that requires a single ratchet and/or filter wrench are handled by the greenest guys.
 
I have a 2017 Legacy with the same FB25, I mix 50/50 Supertech synthetic 0w20 and 5w30, I will probably keep doing it until the motor is old enough to start burning oil (currently 50/50) and then I'll just switch to straight up 5w30.
 
I have used 0w20 and 5w20 in our OB and I usually do 7500 OCI's. I don't think its really going to matter what you use. Whatever helps you sleep at night. These are good engines.
 
Engine protection is paramount. Do whatever you think will protect the engine more. Perhaps thinner oil in Winter and thicker in summer is the smartest choice.
 
Thanks everyone!

SubieRuby - I was waiting for you to chime in. Thanks.

sw99 - you are more than likely correct. I believe the car makers try and "CYA" when it comes to something like oil viscosity.

And my wife just told me to quit "overthinking all things automotive maintenance!"

DOH! That's easy to say when she just drives them.
 
Originally Posted by dkryan
And my wife just told me to quit "overthinking all things automotive maintenance!"

DOH! That's easy to say when she just drives them.


LOL ... +1. Ask her what HTHS or Noack is.
grin2.gif
 
What's to be confused about, if you're going to cane the engine, run the 30...the physics of an engine at high output levels do not change. Subaru is saying what everyone already knows about viscosity, but in an "exceptional" side note. The 'recommended' scale still faithfully follows what they're legally required to print as an outright recommendation in our juridiction. The fact that the cautionary note even made it into their manual is commendable. Of course none of this negates the "just fine" arguments that staunch 0W20 proponents stand by.

If you sleep better knowing you have a viscometrically more robust fill in your crankcase, all the power to you! If you pray to the boundary additive gods at the altar of 'flow', then run 0W20 with the confidence of the additive science and official consensus.
 
My 3.6R is doing fine on the Mobil 1 5W-30 so far (only 10k miles). I figure if it starts burning oil I will switch it to the 10W-30. Engine is great in this car. Touchy throttle though. I barely tap it and the car really takes off. However, I'm still trying to figure out the dipstick. There are two very faint lines between the two holes. I'm not whether to use the lines or the holes.
 
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Originally Posted by ZeeOSix
Originally Posted by dkryan
And my wife just told me to quit "overthinking all things automotive maintenance!"

DOH! That's easy to say when she just drives them.


LOL ... +1. Ask her what HTHS or Noack is.
grin2.gif



If HTHS or Noack is a character in "Game of Thrones," she'd nail it. Otherwise, .......
 
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Originally Posted by MrWideTires
I have a 2017 Legacy with the same FB25, I mix 50/50 Supertech synthetic 0w20 and 5w30, I will probably keep doing it until the motor is old enough to start burning oil (currently 50/50) and then I'll just switch to straight up 5w30.

Since you're in Florida, I don't see using any 0w in your Legacy.
 
Originally Posted by Brigadier
You want confusing oil requirements? Buy a Hyundai....

Why is that?
My (and your) 2018 Santa Fe is pretty clear, use any API Service SM *3, ILSAC GF-4 (or above), ACEA A5 (or above) oil.
It gives you a range of viscosities based on temps. 5w-30 or 5w-40 for all temps, 10w-30 for temps that are not below 0°F.


It has similar wording to the Subaru regarding fuel economy vs protection:
Quote
Engine oil viscosity (thickness) has an effect on fuel economy and cold weather operating (engine start and engine oil flowability).
Lower viscosity engine oils can provide better fuel economy and cold weather performance, however, higher viscosity engine oils are required for satisfactory lubrication in hot weather.
Using oils of any viscosity other than those recommended could result in engine damage.

When choosing an oil, consider the range of temperature your vehicle will be operated in before the next oil change.
Proceed to select the recommended oil viscosity from the chart.

The chart does say use 5w-30 for better fuel economy.

My sisters 2010 Santa Fe with the 2.4 says similar, except the viscosities are 5w-20 or 5w-30 for any temp, 10w-30 for above 0°F, and the chart does say use 5w-20 for fuel economy.

I find it pretty simple to choose oil for this.
 
A couple of months back I change my Foresters 2.5 oil with a 50/50 mix of 0w20 and 5w30 Valvoline Synpower. I saw a Subaru mechanic getting into his newish Forester at the supermarket and asked him what grade oil does he use...
5w30
 
The Subaru manuals have been like this since the 2011 WRX. At first, I thought that this was Subaru of America language but saw that the same language was in a European manual (except with the addition of ACEA A3 oils being allowed). IMO, there's usually no need for anything thicker than 0W-20 in a newer naturally aspirated Subaru. The H6 is old and isn't expected to be around much longer so they haven't bothered to update the oil recommendation in regards to synthetic being "required". Subaru Japan allows 5W-40 in the H6.

sw99 - No doubt the oil will hold up that long, but note that the interval is 6,000 miles for your model year.
 
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Originally Posted by bluesubie


sw99 - No doubt the oil will hold up that long, but note that the interval is 6,000 miles for your model year.


True,but Subaru reduced the miles for the consumption issues that they previously had and was corrected. I see no consumption and I'm going 7500 in 3-4 months at our current rate. Our 18 in not even one year old yet and we are at 33k.
 
Originally Posted by IndyIan
Originally Posted by Miller88
I do wish there were more available options. I'd like coolant temperature too.

I have oil temp, throttle position and trip time.

What's your oil temp run at normally? If I ran the manuals cruising rpm it would be maybe at 210F?. It seems very rpm dependent.
I haven't tried my Ultra Gauge on the Outback yet, as I don't drive it that much, and I found it caused to blank out the Focus's dash once in a while(all warning lights on, no ODO,speedo, or rpm), so I don't use it unless I have a specific issue I'm looking for.


210 or so I have had it up to 225 on the highway during a higher speed run. The highest I saw was 240 or so during a very steep hill climb in the snow where the engine was between 3500 and 4500 RPM for like 7 or 8 minutes
 
Originally Posted by Miller88
Originally Posted by IndyIan
Originally Posted by Miller88
I do wish there were more available options. I'd like coolant temperature too.

I have oil temp, throttle position and trip time.

What's your oil temp run at normally? If I ran the manuals cruising rpm it would be maybe at 210F?. It seems very rpm dependent.
I haven't tried my Ultra Gauge on the Outback yet, as I don't drive it that much, and I found it caused to blank out the Focus's dash once in a while(all warning lights on, no ODO,speedo, or rpm), so I don't use it unless I have a specific issue I'm looking for.


210 or so I have had it up to 225 on the highway during a higher speed run. The highest I saw was 240 or so during a very steep hill climb in the snow where the engine was between 3500 and 4500 RPM for like 7 or 8 minutes

That seems a bit high eh? I guess its no car for track days anyways. I've only towed our small trailer with the canoe on and oil temps were fine for that, but I'm thinking of getting a 5x10 enclosed trailer which will have a bit more drag.
 
I was reading on the Forester forums that some people who run in the deserts and rockies can routinely hit 260F oil temp. I pulled my camper through our Adirondack mountains and never really got above 210 oddly enough. I even put enough cinder blocks in it that I broke my utility trailer and it didn't get out of the ordinary for oil temp.

I think it's just high sustained high engine speeds combined with low vehicle speeds.
 
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