1998 GMC Envoy Owner's Manual - Page 232

Changing a Flat Tire If a tire goes flat, avoid further tire and wheel damage by driving slowly to a level place. Turn on your hazard warning flashers. A CAUTION: I Changing a tire cancause an injury. Thev d c l e can slip off the jack androll over you or other people. You and they could be badly injured. Find a level place to change your tire. To help prevent thevehicle from moving: 1. Set the parkingbrake firmly. 2. Put the shift lever in PARK (P). 3. l b r n off the engine. 4. Put the wheel blocks at the frontand rear of the tire farthest away from the one being changed. That would be the tire on the other sidethe vehicle, at of the opposite end. The following stepswill tell you how to use the jack and change a tire. 5-21