July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!
Power Transfer Unit Case Identification: Notes
WARNING: This page is about a different car, the 2018 Buick Regal TourX and 2018 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
The power transfer unit primary identification label (1) is located on the rear extension housing. The power transfer unit secondary identification stamping (2) is located on the bottom of the main housing.