So the wheels from my wife's Cruze will work on the Sonic I should be picking up this week? I am interested in an answer to this question also for the same reasons as the OP.
We bought 16" winter wheels and tires for her car last fall replace her 18" summer set-up (LTZ/RS Cruze). Didn't want to keep swapping those low profile tires out each season. I own a nice set of 15" studded snows I want to have mounted for my soon to be mine LTZ TurboSonic 5 door so I'll be ready for next winter.
What I wonder about is, is the backspacing and offset the same? I know the drive trains should be the same. Some time well before next fall I will try bolting them on to answer those questions with my own eyes. Oh, and yes, I do know that the Cruze doesn't come with 15" tires/wheels. Does the Volt?