GMC 2006 Envoy Owner's Manual page 433

Be sure the socket end of the extension (C)
connects to the hoist shaft.
3. Insert the socket end
of the extension (C) on
a 45 degree angle
downward into the hoist
drive shaft hole (D).
It is exposed when the
rear gate is open
and is just above the
rear bumper.
4. Turn the wheel wrench counterclockwise to lower
the spare tire. Keep turning the wheel wrench until
the spare tire can be pulled out from under the
vehicle.
If the spare tire does not lower to the ground, the
secondary latch is engaged causing the tire
not to lower. See Secondary Latch System on
page 5-84 for more information.
5-77