2006 GMC Envoy Owner's Manual - Page 435

2. Using the wheel wrench, loosen all the wheel nuts. Do not remove them yet. 3. Turn the jack adjusting knob clockwise by hand to raise the jack lift head. 4. Place the handle, extension and wheel wrench onto the jack. Front Position A. Front Frame/ Rear Axle B. Jack Rear Position C. Handle D. Extension(s) E. Wheel Wrench 5. Place the jack in the appropriate position nearest the flat tire. {CAUTION: Getting under a vehicle when it is jacked up is dangerous. If the vehicle slips off the jack you could be badly injured or killed. Never get under a vehicle when it is supported only by a jack. 5-79