Buick 2005 LeSabre Owner's Manual page 313

4. Turn the wheel wrench counterclockwise to lower
the jack head until it fits under the vehicle.
5. Put the jack into a notch in the frame which is
located near each wheel well.
The front notch is 8 inches (20 cm) back from the
front wheel well. The rear notch is 3 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.
6. 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.
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