GMC 1999 Suburban Owner's Manual page 269

CAUTION:
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.
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.
Front Position
4. With UP on the ratchet facing you, raise the vehicle
by rotating the ratchet and wheel wrench clockwise.
Raise the vehicle far enough off the ground so there
is enough room for the spare tire to fit.
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Rear Position
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