Deciding on oil for 2001 Subaru H6 outback

[Dupree]

Ok I am looking at doing first oil change on a new to me 2001 Subaru outback ez30d 4eat 98,000 miles.
Live in utah winters reach -10 consistent in january/febuary with low snaps around -20 have seen -36 before though. Summers reach temps of 90 consistent, with snaps to 100 seen 105 as extreme.
This isn't my first or last Subie, but it is my first H6 Subie. I am planning complete atf change, front and rear axles to 75w-90 and of course a coolant change as well as all needed 100k maintenance.
Have run a tank with redline s1 through fuel, now ready to do 1st engine oil change (did 4 qts in transmission already with maxlife atf).
Here is what i'm narrowing it down to, and I know the opinions are going to fly lol, that's what i'm looking for.
Mobil 1 0w-40
Mobil 1 0w-30
Mobil 1HM 5w-30
Mobil 1HM 10w-30
I haven't noticed any oil weeping or consumption, so I was leaning on the 0 series over the HM, unless it gets to a point of leaks then ill consider HM
so far love the car, ive always run ej22 subaru motors this one is unique, kind of a dog on the bottom but wow much more top end.

 

[901Memphis]

Above -4 F......10W-30, 10W-40
Above 95 F......30, 40, 10W-50, 20W-40, 20W-50
Below 104 F......5W-30


Probably the Mobil 1 0w40 since your vehicle allows for up to a 20w50 in the heat. The 5w30 would be fine too but the M1 0w40 is so robust i wouldn't want to pass it up. Second choice would be the 0w30 AFE.

I wouldn't even consider the 10w30 HM M1, as it doesn't have the better cold flow characteristics of the lighter grades and is still pretty heavy at 100C.

 

[toneydoc]

Use the Mobil 1 0w40 and call it all good. That will cover the entire range of temps that you have mentioned. And you know it is a fine oil that will last a long time. My 2 pennies.

 

[05LGTLtd]

I'll follow the crowd, M1 0w-40. For the price it is a heck of an oil. I don't have much much love for the M1 0w-30, but you could blend in a quart or two in the winter time if you wanted to get in the middle of the 30 grade range.

The H6 is a good engine. I've seen them run a good distance with very little attention.

Subaru offers a block heater, which might not be too bad an idea at -20*...

 

[bluesubie]

gpshumway has several H6 uoa's on Mobil1 0W-30 and 0W-40, but I'm having a bit of a search fail at the moment. Maybe he'll chime in soon.

-Dennis

 

[Eddie]

I'd pick a 5w30 oil as the best all around oil for your application since 0w oils are not listed as prefered.

 

[05LGTLtd]

Also don't forget to change your coolant with either Subaru Genuine Coolant or a complete flush and Run Peak Global Lifetime.

While you have the ATF out might be a good idea to flush the power steering system too.

 

[Dupree]

Originally Posted By: 05LGTLtd
Also don't forget to change your coolant with either Subaru Genuine Coolant or a complete flush and Run Peak Global Lifetime.

While you have the ATF out might be a good idea to flush the power steering system too.


I planned on doing the power steering this weekend along with new serpantine, and idler pulleys. The coolant I assumed was just regular green, am I wrong on this ?

 

[901Memphis]

It's not conventional green!