GMC 2003 Savana Van Owner's Manual page 323

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.
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.
4. Raise the vehicle by turning the ratchet clockwise.
Make sure the UP mark faces you. Raise the
vehicle far enough off the ground so there is enough
room for the spare tire to fit.
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