Chevrolet TRACKER 2003 Manual page 281

Rear Wheel Location
3. Under the vehicle near each wheel, there are knobs
in the vehicle's frame. Raise the jack
2
inches
(51 mm) before positioning the jack. Raise the jack
lift head until it fits firmly onto the knobs nearest
to the flat tire.
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 cause personal injury and
damage to the vehicle. If you try to use the
jack when it hasn't been raised at least
2 inches (51 mm), the jack may not hold up the
vehicle, and you or others could be injured. To
help avoid personal injury and vehicle damage,
be sure to open the jack at least 2 inches
(51 mm) before you fit the lift head into the
proper location.
5-72