I know Honda specifies their coolant as the only one to use. Does Subaru require OEM spec coolant or will Prestone be just fine?

Stick to something alkaline, and you'll be okay.

 

 

Be aware that most long-life stuff is acidic, and will not mix with the old coolant that is left in your engine.

Can anyone point me to evidence showing conclusively that Subaru's pricey OEM coolant IS, in fact, superior in performance to lower priced ones?

I'm looking for FACT, not opinion.

Edited January 25, 201115 yr by Bluestone

Unsure, but in the summers I regularly run my radiator on 100% water.

Just run the plain old green stuff.

The new "Super Blue" is a long life coolant. Much like GM's Dexcool, etc. Honda has one as does Toyota, etc.

 

It is my opinion that Subaru caved in to customer's wanting a "long life" coolant but having no real conception of why they wanted it. The usual questions I'm sure..... "My Toyota has 5 year coolant - why doesn't Subaru do that?". Basically it's marketing - yes it's $20 a gallon (premixed so you need 2 for a total of $40 for a fill) - and yes all the new Subaru's for a bit now are coming with it pre-installed.

 

The reason Subaru held out so long against moving to this long-life coolant craze is that Subaru's, by and large, don't have problems with cooling system corrosion. The engine is alumiunium - so is the radiator and heater core. Then the tanks are plastic and there's a bunch of rubber rounding out the mix. There's very little opportunity for dissimilar metal reactions. I have NEVER seen pitting on a Subaru caused by galvanic corrosion.

 

So is it out there? Yes - they now make the Subaru Super Blue.

 

Is it neccesary? IMHO - no it is not. I run the green stuff in all of mine. I will likely continue to use the Super Blue in my 2010 Forester.... at least till it becomes a problem child and starts consuming the stuff. I am not going to play that game for long at $20 a gallon. It's 4 times the price of plain green when you consider I get 2 gallons of green for $10 (concentrate).

 

GD

There was quite a thread on this subject on another site in the fall. Can't seem to lacate it right now. By the end of the thread someone had been in touch with the makers of Peak. Peak Global Lifetime and Peak Long Life were matches to the subaru coolant minus the stop leak additive. I have been running it since 2004 when some crazy porupine gnawed some hoses......