2HI GMC ENVOY 2003 Owner's Manual

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 won't shift into ®rst
gear until the vehicle is going slowly enough.
Notice:If your wheels won't turn, don't try to drive.
This might happen if you were stuck in very deep
sand or mud or were up against a solid object. You
could damage your transmission. Also, if you
stop when going uphill, don't hold your vehicle there
with only the accelerator pedal. This could overheat
and damage the transmission. Use your brakes
or shift into PARK (P) to hold your vehicle in
position on a hill.
Four-Wheel Drive
If your vehicle has four-wheel drive, you can send your
engine's driving power to all four wheels for extra
traction. To get the most satisfaction out of four-wheel
drive, you must be familiar with its operation. Read
the part that follows before using four-wheel drive. You
should use two-wheel drive high (2HI) for most
normal driving conditions.
Notice:Driving in the 4-WHEEL HIGH (4HI) or
4-WHEEL LOW (4LO) positions for a long time on
dry or wet pavement could shorten the life of
your vehicle's drivetrain.
Automatic Transfer Case
If your vehicle is equipped
with four-wheel drive, the
transfer case knob is
located to the right of the
steering wheel on the
instrument panel. Use this
knob to shift into and
out of four-wheel drive.
2HI (Two-Wheel High):This setting is for driving in
most street and highway situations. Your front axle is not
engaged in two-wheel drive. It also provides the best
fuel economy.
A4WD (Automatic Four-Wheel Drive):This setting is
ideal for use when road conditions are variable.
When driving your vehicle in A4WD, the front axle is
engaged, but the vehicle's power is sent to the
rear wheels. When the vehicle senses a loss of traction,
the system will automatically engage four-wheel
drive. Driving in this mode results in slightly lower fuel
economy than 2HI.
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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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Shifting into 4LO
To shift to 4LO, the vehicle's engine must be running
and the vehicle must be stopped or moving less
than 2 mph (3.2 km/h) with the transmission in
NEUTRAL (N). The preferred method for shifting into
4LO is to have your vehicle moving 1 or 2 mph (1.6 to
3.2 km/h). Turn the knob to 4LO. You must wait for
the 4LO indicator light to stop ¯ashing and remain
illuminated before shifting your transmission into gear.
If you turn the knob to 4LO when your vehicle is in gear
and/or moving, the 4LO indicator light will ¯ash for
30 seconds and not complete the shift unless your
vehicle is moving less than 2 mph (3.2 km/h) and the
transmission is in NEUTRAL (N). After 30 seconds, the
transfer case will return to the setting last chosen.
Shifting Out of 4LO
To shift from 4LO to 4HI, A4WD or 2HI your vehicle
must be stopped or moving less than 2 mph (3.2 km/h)
with the transmission in NEUTRAL (N) and the
engine running. The preferred method for shifting out of
4LO is to have your vehicle moving 1 or 2 mph (1.6
to 3.2 km/h). Turn the knob to 4HI, A4WD or 2HI. You
must wait for the 4HI, A4WD or 2HI indicator light to stop
¯ashing and remain illuminated before shifting your
transmission into gear.If the knob is turned to 4HI, A4WD or 2HI when your
vehicle is in gear and/or moving, the 4HI, A4WD or 2HI
indicator light will ¯ash for 30 seconds. It will not
complete the shift unless your vehicle is moving less
than 2 mph (3.2 km/h) with the transmission in
NEUTRAL (N).
Shifting into NEUTRAL
Before shifting the transfer case to NEUTRAL, ®rst
make sure the vehicle is parked so that it will not roll.
1. Set the parking brake.
2. Start the vehicle.
3. Put the transmission in NEUTRAL (N).
4. Shift the transfer case to 2HI.
5. Turn the transfer case knob all of the way past 4LO
and hold it there for a minimum of 10 seconds. The
neutral indicator light will come on.
6. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second.
7. Place the transmission shift lever in PARK (P).
8. Release the parking brake prior to towing.
9. Turn the ignition to LOCK.
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Shifting Out of NEUTRAL
To shift the transfer case out of NEUTRAL, do the
following:
1. Set the parking brake and apply the regular
brake pedal.
2. Start the vehicle with the transmission in PARK (P).
3. Turn the transfer case knob to the desired shift
position (2HI, 4HI or A4WD).
4. Put the transmission in NEUTRAL (N).
5. Release the parking brake.
6. After the transfer case has shifted out of NEUTRAL,
the indicator light will go out. Shift the transmission
lever to the desired position.
A re-engagement sound is normal when shifting out of
NEUTRAL.
Parking Brake
To set the parking brake, hold the regular brake pedal
down with your right foot and pull up on the parking
brake lever. If the ignition is on, the brake system
warning light will come on.
To release the parking brake, hold the regular brake
pedal down. Pull the parking brake lever up until you can
press in the button at the end of the lever. Hold the
button in as you move the parking brake lever all the
way down.
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