GMC 2007 Envoy - Manual (Page 119)

{ CAUTION:
If you have four-wheel drive, your vehicle
will be free to roll — even if your shift
lever is in PARK (P) — if your transfer
case is in NEUTRAL. So, be sure the
transfer case is in a drive gear — not in
NEUTRAL. See Four-Wheel Drive on
page 122. See Shifting Into Park (P) on
page 127.
Make sure the shift lever is fully in PARK (P)
before starting the engine. Your vehicle has an
automatic transmission shift lock control system.
You have to fully apply the regular brakes first and
then press the shift lever button before you can
shift from PARK (P) when the ignition key is
in RUN. If you cannot shift out of PARK (P), ease
pressure on the shift lever and push the shift
lever all the way into PARK (P) as you maintain
brake application. Then press the shift lever button
and move the shift lever into another gear. See
Shifting Out of Park (P) on page 129.
REVERSE (R): Use this gear to back up.
Notice: Shifting to REVERSE (R) while your
vehicle is moving forward could damage the
transmission. The repairs would not be covered
by your warranty. Shift to REVERSE (R) only
after your vehicle is stopped.
To rock your vehicle back and forth to get out of
snow, ice, or sand without damaging your
transmission, see If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow on page 348.
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