GMC 2005 Safari Owner's Manual page 285

CAUTION:
{
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even
make the vehicle fall. To help avoid personal
injury and vehicle damage, be sure to fit the
jack lift head into the proper location before
raising the vehicle.
2. With the DOWN side facing you, turn the ratchet
and socket to loosen all the wheel nuts
counterclockwise. Don't remove them yet.
3. Attach the socket end of the extension to the
jack bolt.
4. Attach the ratchet to the extension with the UP side
facing you.
5. Turn the ratchet clockwise. That will raise the jack
lift head a little.
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