Pontiac 2003 Montana Owner's Manual page 308

Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. If your vehicle
has traction control, you should turn your traction
control system off. See Traction Control System (TCS)
on page 4-9. Then shift back and forth between
REVERSE (R) and a forward gear, spinning the wheels
as little as possible. Release the accelerator pedal
while you shift, and press lightly on the accelerator
pedal when the transaxle is in gear. By slowly spinning
your wheels in the forward and reverse directions,
you will cause a rocking motion that may free your
vehicle. If that doesn't get you out after a few tries, you
may need to be towed out. If you do need to be
towed out, see "Towing Your Vehicle" following.
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