Buick 2007 Rainier Owner's Manual page 117

To shift to the SECOND (2) position, you must first
press the large button on the shift handle. While
the button is pressed, move the shifter in the
SECOND (2) position.
You can also use SECOND (2) for starting the
vehicle from a stop on slippery road surfaces.
FIRST (1): This position reduces vehicle speed
even more than SECOND (2) without using
your brakes. You can use it on very steep hills, or
in deep snow or mud. If the shift lever is put in
FIRST (1) while the vehicle is moving forward, the
transmission will not shift into first gear until the
vehicle is going slowly enough.
To shift to the FIRST (1) position, you must
first press the large button on the shift handle.
While the button is pressed, move the shifter in
the FIRST (1) position.
Notice: Spinning the tires or holding the
vehicle in one place on a hill using only the
accelerator pedal may damage the
transmission. The repair will not be covered by
your warranty. If you are stuck, do not spin
the tires. When stopping on a hill, use the
brakes to hold the vehicle in place.
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