the battery! I purchased my 13 mid summer in 13. Although my garage didn't quite get down to the -9° it was this morning, it is not heated so it was pretty cold. As always the cranking rpms were really high. This with Mobil 1 5W-30. The thing is, our 17 Forester, with Mobil 1 0W-20 and only four cylinders cranks slow when it is even 20°! Don't get me wrong though, have purchased many Subarus and love them.