GMC 2006 Envoy Owner's Manual page 106

Notice: Shifting out of PARK (P) or NEUTRAL (N)
with the engine running at high speed may damage
the transmission. The repairs would not be
covered by your warranty. Be sure the engine is not
running at high speed when shifting your vehicle.
DRIVE (D): This position is for normal driving. If
you need more power for passing, and you are:
•
Going less than about 35 mph (55 km/h), push the
accelerator pedal about halfway down.
•
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
You will shift down to the next gear and have
more power.
DRIVE (D) can be used when towing a trailer, carrying a
heavy load, driving on steep hills, or for off-road
driving. You may want to shift the transmission to
THIRD (3) or, if necessary, a lower gear selection if the
transmission shifts too often.
THIRD (3): This position is also used for normal driving.
However, it offers more power and lower fuel economy
than DRIVE (D).
To shift to the THIRD (3) position, you must first press
the large button on the shift handle. While the button
is pressed, move the shifter in the THIRD (3) position.
2-26
SECOND (2): This position gives you more power but
lower fuel economy than THIRD (3). You can use
SECOND (2) on hills. It can help control your speed as
you go down steep mountain roads, but then you
would also want to use the brakes off and on.
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 gives you even more power
but lower fuel economy than SECOND (2). You can use
it on very steep hills, or in deep snow or mud. If the
selector 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. If you are
stuck, do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.