CHEVROLET 2010 Express - Manual (Page 368)

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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