GMC SIERRA 2004 Owner's Manual

Recommended Transfer Case Settings
Transfer Case Settings
Driving Conditions 2HI 4HI 4LO N
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*See
Recreational Vehicle Towing on page 4-54orTowing Your Vehicle on page 4-53for further
information.
An indicator on the bezel near the lever shows you the
transfer case settings:
2-Wheel High (2HI):This setting is used for driving in
most street and highway situations. Your front axle
is not engaged in two-wheel drive. This setting
also provides the best fuel economy.
4-Wheel High (4HI):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. This is the best setting
to use when plowing snow.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P), or if you have a
manual transmission, even if you are in gear.
You or someone else could be seriously
injured. Be sure to set the parking brake
before placing the transfer case in NEUTRAL.
See
Parking Brake on page 2-48.
2-37

NEUTRAL (N):Shift to this setting only when your
vehicle needs to be towed. SeeRecreational Vehicle
Towing on page 4-54orTowing Your Vehicle on
page 4-53.
4-Wheel Low (4L0):This setting also engages your
front axle and delivers extra torque. You may never
need 4LO. It sends maximum power to all four wheels.
You might choose 4LO if you are driving off-road in
deep sand, deep mud, deep snow and climbing
or descending steep hills.
You can shift from 2-Wheel High (2HI) to 4-Wheel High
(4HI) or from 4-Wheel High (4HI) to 2-Wheel High
(2HI) while the vehicle is moving. Your front axle will
engage faster if you take your foot off of the accelerator
for a couple of seconds after you shift. In extremely
cold weather, it may be necessary to stop or slow the
vehicle to shift into 4-Wheel High (4HI).
When Using the Manual Transfer Case
·
All shifts should be made using quick motions. Slow
shifts may make it harder to shift.
·You may notice that it is harder to shift when the
vehicle is cold. When the vehicle warms up the
shifting will return to normal.
·While in 4-Wheel (4HI) or 4-Wheel Lo (4LO) you
may experience reduced fuel economy.
·Avoid driving in 4-Wheel Drive on clean, dry
pavement. It may cause your tires to wear faster, and
make your transfer case harder to shift and run
noisier.
Shifting from 2HI to 4HI
·
Shifts between 2HI and 4HI can be made at any
vehicle speed.
·It is easiest to shift the transfer case when
maintaining a constant speed or a slight
acceleration. If possible, avoid shifting while slowing
down, as it will may make it harder to shift.
·Shift your transfer case lever in one continuous
motion into either the 4HI or 2HI position.
·In extremely cold weather, it may be necessary to
slow or stop the vehicle to shift into 4HI until your
vehicle has warmed up.
·While in 4HI, your vehicle can be driven at any
posted legal speed limit.
2-38

Shifting In or Out of 4LO
Notice:Shifting the transfer case into 4LO while
moving at speeds faster than 3 mph (5 km/h)
may cause premature wear to the transfer case, and
may cause the gears to grind. To avoid causing
premature wear, and grinding the gears, do not shift
the transfer case into 4LO while the vehicle is
moving faster than 3 mph (5 km/h).
Shifts into 4LO can be made with the vehicle at a stop,
or while slowly rolling about 1 to 3 mph (2 to 5 km/h).
·Shift the automatic transmission into NEUTRAL
(N), or with a manual transmission, press the
clutch pedal, or shift into NEUTRAL (N).
·Shift the transfer case shift lever in one continuous
motion into the 4LO position.
·When in 4LO do not drive faster than 45 mph.
This will reduce wear and extend the life of
your transfer case.
Shifting In or Out of NEUTRAL
1. With the vehicle running and the engine at an idle
set the parking brake.
2. Place the transmission into NEUTRAL (N).
Shift the transfer case in one continuous motion into or
out of the NEUTRAL (N) position.
Automatic Transfer Case
The transfer case buttons
are located to the left of
the instrument panel
cluster.
Use these switches to shift into and out of four-wheel
drive.
2-39

Recommended Transfer Case Settings
Transfer Case Settings
Driving
Conditions2HIAUTO
4WD4HI 4LO N
Normal YES
Variable YES
Severe YES
Extreme YES
Vehicle in
Tow*YES
*See ªRecreational Vehicle Towingº in the Index for
further information.
You can choose among four driving settings:
h(2HI):This setting is used for driving in most street
and highway situations. Your front axle is not engaged
in two- wheel drive. This setting also provides the
best fuel economy.AUTO 4WD:This setting is ideal for use when road
conditions are variable. When driving your vehicle
in AUTO 4WD, 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.
G(4HI):Use 4HI when you need extra traction, such
a on snowy or icy roads or in most off-road situations.
This setting also engages your front axle to help
drive your vehicle. This is the best setting to use when
plowing snow.
g(4LO):This setting also engages your front axle
and delivers extra torque. You may never need 4LO. It
sends maximum power to all four wheels. You might
choose 4LO if you are driving off-road in deep
sand, deep mud, deep snow and climbing or descending
steep hills.
2-40

{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
Parking Brake on
page 2-48
.
NEUTRAL:Shift the vehicle's transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-54orTowing
Your Vehicle on page 4-53for more information.Indicator lights in the switches show which setting your
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 the transfer case is being shifted. 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 4WD light stays on, you should take
your vehicle to your dealer for service. See
Service on
page 5-3for further information.
Shifting into 4HI or AUTO 4WD
Press and release the 4HI or AUTO 4WD switch. This
can be done at any speed (except when shifting
from 4LO), and the indicator light will ¯ash while shifting.
It will remain illuminated when the shift is completed.
Shifting into 2HI
Press and release the 2HI switch. This can be done at
any speed (except when shifting from 4LO).
2-41

Shifting into 4LO
To shift to 4LO, the ignition must be in RUN and the
vehicle must be stopped or moving less than 3 mph
(4.8 km/h) with the transmission in NEUTRAL (N). The
preferred method for shifting into 4LO is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press
and release the 4LO switch. You must wait for the
4LO indicator light to stop ¯ashing and remain
illuminated before shifting your transmission in gear.
Notice:Shifting the transmission into gear before
the 4LO indicator light has stopped ¯ashing
could damage the transfer case. To help avoid
damaging your vehicle, always wait for the
4LO indicator light to stop ¯ashing before shifting
the transmission into gear.
It is typical for your vehicle to exhibit signi®cant
engagement noise and bump when shifting between
4LO and 4HI ranges or from NEUTRAL with the engine
running.
If the 4LO switch is pressed 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 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N). After 30 seconds
the transfer case will shift to 4HI mode.
Shifting Out of 4LO
To shift from 4LO to 4HI, AUTO 4WD or 2HI your vehicle
must be stopped or moving less than 3 mph (4.8 km/h)
with the transmission in NEUTRAL (N) and the ignition in
RUN. The preferred method for shifting out of 4LO is to
have your vehicle moving 1 to 2 mph
(1.6 to 3.2 km/h). Press and release the 4HI, AUTO 4WD
or 2HI switch. You must wait for the 4HI, AUTO 4WD or
2HI indicator light to stop ¯ashing and remain illuminated
before shifting your transmission into gear.
Notice:Shifting the transmission into gear before
the 4LO indicator light has stopped ¯ashing
could damage the transfer case. To help avoid
damaging your vehicle, always wait for the
4LO indicator light to stop ¯ashing before shifting
the transmission into gear.
It is typical for your vehicle to exhibit signi®cant
engagement noise and bump when shifting between
4LO and 4HI ranges or from NEUTRAL with the engine
running.
If the 4HI, AUTO 4WD or 2HI switch is pressed when
your vehicle is in gear and/or moving, the 4HI,
AUTO 4WD or 2HI indicator light will ¯ash for
30 seconds but will not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and
the transmission is in NEUTRAL (N).
2-42

Shifting into NEUTRAL
To shift the transfer case to NEUTRAL do the following:
1. Make sure the vehicle is parked so that it will
not roll.
2. Set the parking brake.
3. Start the vehicle or turn the ignition to RUN.
4. Connect the vehicle to the towing vehicle.
5. Put the transmission in NEUTRAL (N).
6. Shift the transfer case to 2HI.
7. Simultaneously press and hold the 2HI and
4LO buttons for 10 seconds. The red NEUTRAL
light will come on when the transfer case shift
to NEUTRAL is complete.
8. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second.
9. Turn the ignition to OFF.
10. Place the transmission shift lever in PARK (P).
11. Release the parking brake prior to towing.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (2HI, 4HI, AUTO 4WD or 4LO).
4. After the transfer case has shifted out of NEUTRAL
the red light will go out.
5. Release the parking brake.
6. You may start the engine and shift the transmission
to the desired position.
Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to enter the
shift protection mode. This will protect the transfer case
from possible damage and will only allow the transfer
case to respond to one shift per 10 seconds. The transfer
case may stay in this mode for up to three minutes.
2-43

Electronic Transfer Case
If your four-wheel-drive
vehicle has the electronic
transfer case, the
transfer case switches are
located to the left of the
instrument panel cluster.Use these switches to shift into and out of four-wheel
drive. You can choose among three driving settings:
Recommended Transfer Case Settings
Transfer Case Settings
Driving Conditions 2HI 4HI 4LO N
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*See
Recreational Vehicle Towing on page 4-54orTowing Your Vehicle on page 4-53for further
information.
h(2HI):This setting is for driving in most street and
highway situations. Your front axle is not engaged
in two-wheel drive.
G(4HI):This setting engages your front axle to help
drive your vehicle. Use 4HI when you need extra
traction, such as on snowy or icy roads, or in most
off-road situations.
2-44

g(4LO):This setting also engages your front axle to
give you extra traction. You may never need 4LO. It
sends the maximum power to all four wheels. You might
choose 4LO if you were driving off-road in sand, mud
or deep snow and climbing or descending steep hills.
Indicator lights in the switches show you which
setting you are in. The indicator lights will come on
brie¯y when you turn on the ignition and the last chosen
setting will stay on. If the lights do not come on, you
should take your vehicle in for service. An indicator light
will ¯ash while shifting. It will remain illuminated when
the shift is completed. If for some reason the transfer
cannot make a requested shift, it will return to the
last chosen setting.
{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
Parking Brake on
page 2-48
.
NEUTRAL:Shift the vehicle's transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-54orTowing
Your Vehicle on page 4-53for more information.
Shifting from 2HI to 4HI
Press and release the 4HI switch. This can be done at
any speed, and the front axle will lock automatically
with some delay.
Shifting from 4HI to 2HI
Press and release the 2HI switch. This can be done at
any speed, and the front axle will unlock automatically
with some delay.
2-45

Shifting from 2HI or 4HI to 4LO
To shift from 2HI or 4HI to 4LO, the vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with the
transmission in NEUTRAL (N). The preferred method
for shifting into 4LO is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Press and release the
4LO switch. You must wait for the 4LO indicator light to
stop ¯ashing and remain illuminated before shifting
your transmission into gear.
Notice:Shifting the transmission into gear before
the 4LO indicator light has stopped ¯ashing
could damage the transfer case. To help avoid
damaging your vehicle, always wait for the
4LO indicator light to stop ¯ashing before shifting
the transmission into gear.
If the 4LO switch is pressed 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 slower than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N). The transfer case
will shift to 4HI while waiting to complete the shift.
Shifting from 4LO to 4HI or 2HI
To shift from 4LO to 4HI or 2HI, your vehicle must be
stopped or moving less than 3 mph (4.8 km/h) with
the transmission in NEUTRAL (N). The preferred method
for shifting out of 4LO is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Press and release the 4HI
switch. You must wait for the 4HI indicator light to
stop ¯ashing and remain illuminated before shifting your
transmission into gear.
If the 4HI switch is pressed when your vehicle is in gear
and/or moving, the 4HI indicator light will ¯ash for
30 seconds but will not complete the shift unless the
vehicle is moving slower than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N).
Shifting into NEUTRAL
To shift 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 or turn the ignition to RUN.
3. Connect the vehicle to the towing vehicle.
4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to 2HI.
2-46