Buick 2003 LeSabre Owner's Manual page 325

3. Turn the wheel wrench counterclockwise to lower
the jack head until it fits under the vehicle.
4. Put the jack into a notch in the frame which is
located near each wheel well. The front notch is
eight inches (20 cm) back from the front wheel well.
The rear notch is three inches (8 cm) forward
from the rear wheel well. The notches are
accessible through openings in the plastic trim at
the bottom of the vehicle.
Position the jack and raise the jack head until it fits
firmly on the ridge in the vehicle's frame nearest
the flat tire. Do not raise the vehicle yet. Put the
compact spare tire near you.
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