GMC 2003 Sonoma Owner's Manual page 341

A. Front Frame Hole
B. Rear Frame Hole (ZR2)
C. Spring Hanger Hole (Standard Pickups)
1
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.
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