Originally Posted by JTK
I know the series of late model Subarus I owned had ridiculously low CCA batteries in them. They would likely never start at the temps in the above clips.
My Forester's OEM battery was fine at low temperatures when new, but was replaced under warranty when it barely managed to start at 30 below zero after a year or two, and showed as a dismal failure on the dealer's battery testing machine. The replacement had twice the CCAs, and I believe that's now the standard OEM battery for Canadian Subarus.
Now I have a battery heater as well, so I never have to worry about starting if the car has been plugged in. And, so far, I haven't had any problem starting it with the new battery when it's not plugged in.