Service 4wd GMC ENVOY 2003 Owner's Manual

4HI (Four-Wheel High):Use 4HI when you need extra
traction, such as on snowy or icy roads or in most
off-road situations. This setting also engages your front
axle to help drive your vehicle.
4LO (Four-Wheel Low):This setting also engages
your front axle and delivers extra torque. It sends
maximum power to all four wheels. You might choose
4LO if you are driving off-road in deep sand, deep mud,
and climbing or descending steep hills.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. See ªParking Brakeº in
the Index.
NEUTRAL:Shift the vehicle's transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-45for more
information.An indicator light in the knob will show you which
position the transfer case is in. The indicator lights will
come on brie¯y when you turn on the ignition and
one will stay on. If the lights do not come on, you should
take your vehicle to your dealer for service. An
indicator light will ¯ash while shifting the transfer case. It
will remain illuminated when the shift is complete. If
for some reason the transfer case cannot make a
requested shift, it will return to the last chosen setting.
If the service four-wheel drive light on the instrument
panel cluster stays on, you should take your vehicle to
your dealer for service. See
Service Four-Wheel
Drive Warning Light on page 3-48for further information.
Shifting into 4HI or A4WD
Turn the knob to 4HI or A4WD. This can be done at any
speed unless you are shifting out of 4LO. The indicator
light will ¯ash while shifting. It will remain illuminated
when the shift is complete.
Shifting into 2HI
Turn the knob to 2HI. This can be done at any speed
unless you are shifting out of 4LO.
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Service Four-Wheel Drive
Warning Light
This light should come on brie¯y when you turn on the
ignition, as a check to show you it is working.
The SERVICE 4WD light comes on to indicate that
there may be a problem with the drive system and
service is required. Malfunctions can be indicated by the
system before any problem is apparent, which may
prevent serious damage to the vehicle. This system is
also designed to assist your service technician in
correctly diagnosing a malfunction.
Check Gages Warning Light
The CHECK GAGES light will come on brie¯y when you
are starting the engine.
If the light comes on and stays on while you are driving,
check your coolant temperature and engine oil
pressure gages to see if they are in the warning zones. United StatesCanada
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