So this coolant business has been real confusing for me.  My 2009 Impreza 2.5i is right on the cusp of the color change from green to blue.  When I noticed it was low, I swear I was seeing green at the bottom of the res... so I added green.  But the dealership is telling me blue ("you must get it in, green is corrosive!!!"), the town mechanic is telling me green is fine...who do I trust?  Is it necessary to pay 130$ to have it flushed and make the switch to blue?

Thanks everybody

Final Word? Probably won't find that. Yes, your car probably came from the factory with Blue, and was probably engineered assuming that it would continue having blue. Does that mean that green will destroy your car? Probably not.

 

My mom's 2012 Impreza has been running green for 150k miles...no problem.

Definitely do not mix them, though.

Yes, it made me nervous when I read about mixing them.  But I'm ... 90% certain I saw green before I topped it off.

 

I was mostly curious about how corrosive green was over time.  so thanks for mentioning your mother's car.

It's completely irrelevant. You can run either. Nothing bad is going to happen (unless you mix them). Subaru switched (to OAT coolant) because everyone else is switching - if anything the blue coolant eats the plastic radiators quicker (which you should change soon as it's beyond it's fail-by date - we have seen a huge rash of 11's with blown radiators due to the blue coolant softening the plastic). I would run the green, install a new radiator (and whatever component is leaking coolant), new OEM hoses, and call it a day. 

GD

Edited September 18, 20205 yr by GeneralDisorder