2008 Cadillac CTS Owner's Manual - Page 392

Storing a Flat or Spare Tire and Tools Use the following diagram as a guide for storing the compact spare tire in the trunk: {CAUTION: Storing a jack, a tire, or other equipment in the passenger compartment of the vehicle could cause injury. In a sudden stop or collision, loose equipment could strike someone. Store all these in the proper place. After you have put the compact spare tire on your vehicle, you will need to store the flat tire in your trunk. The compact spare is for temporary use only. Replace the compact spare tire with a full-size tire as soon as you can. A. Wing Nut B. Compact Spare Tire or Flat Tire (valve stem down) C. D. E. F. Jack Wheel Wrench Extension Strap 5-110