Chevrolet 2009 Express Owner's Manual page 335

3. Attach the jack handle/jack handle extension and
wheel wrench to the jack.
4. Place the jack under the vehicle, ahead of the rear
bumper. Position the center lift point of the jack
under the center of the spare tire and turn the handle
clockwise to raise the jack until it lifts the secondary
latch spring.
5. Keep raising the jack until the spare tire stops
moving upward and is held firmly in place. This lets
you know that the secondary latch has released.
The spare tire is now balancing on the jack.
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