ya, I think so...or maybe a little smaller...I think it's the only available size from the dealer, but you still need to add a mix of 50/50 with water so it's ok I guess.
I've added about 1/2 gallon of the Subaru coolant (mixed with 50% h2o of course), doing it this way...hope I didn't mess anything up...but just wanna know you know...I can always change my "bad habits"