tow GMC SIERRA 2005 Owner's Guide

NEUTRAL (N):Shift to this setting only when your
vehicle needs to be towed. SeeRecreational Vehicle
Towing on page 4-62orTowing Your Vehicle on
page 4-62.
4-Wheel Low (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. When operating in 4LO, the
gear ratio is extra deep when compared to 4HI. The
transmission gear shift feel will be exaggerated.
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 High (4HI) or 4-Wheel Low (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.
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Recommended Transfer Case Settings
Driving
ConditionsTransfer Case Settings
2HIAUTO
4WD4HI 4LO N
Normal YES
Variable YES
Severe YES
Extreme YES
Vehicle in
Tow*YES
*See “Recreational Vehicle Towing” in the Index for
further information.
You can choose among four driving settings:
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.
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.
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. When
operating in 4LO, the gear ratio is extra deep when
compared to 4HI. The transmission gear shift feel will be
exaggerated.
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{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. SeeParking 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 4-62orTowing
Your Vehicle on page 4-62for more information.
Indicator lights in the switches show which setting your
transfer case is in. The indicator lights will come on
briey 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 message stays on, you should
take your vehicle to your dealer for service. See
DIC Warnings and Messages on page 3-54for 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).
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.
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You can choose among three driving settings:
Recommended Transfer Case Settings
Driving ConditionsTransfer Case Settings
2HI 4HI 4LO N
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*SeeRecreational Vehicle Towing on page 4-62or
Towing Your Vehicle on page 4-62for 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.
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.When operating in 4LO, the gear ratio is extra deep when
compared to 4HI. The transmission gear shift feel will be
exaggerated.
Indicator lights in the switches show you which setting
you are in. The indicator lights will come on briey 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. SeeParking 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 4-62orTowing
Your Vehicle on page 4-62for more information.
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Parking Brake
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking
brake pedal with your left foot.
A chime will activate and the warning light will ash
when the parking brake is applied and the vehicle
is moving at least 3 mph (5 km/h) for at least
three seconds.To release the parking brake, hold the regular brake
pedal down. Pull the bottom edge of the lever, located
above the parking brake pedal, with the parking
brake symbol, to release the parking brake.
If the ignition is on when the parking brake is released,
the brake system warning light will go off.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Verify that
the parking brake is fully released and the brake
warning light is off before driving.
If you are towing a trailer and are parking on any hill,
seeTowing a Trailer on page 4-68.
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Shifting Into Park (P)
(Automatic Transmission)
{CAUTION:
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brake rmly set. Your vehicle can
roll. If you have left the engine running, the
vehicle can move suddenly. You or others
could be injured. To be sure your vehicle will
not move, even when you are on fairly level
ground, use the steps that follow. With
four-wheel drive, if your transfer case is in
NEUTRAL, your vehicle will be free to roll,
even if your shift lever is in PARK (P). So, be
sure the transfer case is in a drive gear — not
in NEUTRAL. If you are pulling a trailer, see
Towing a Trailer on page 4-68.1. Hold the brake pedal down with your right foot and
set the parking brake.
2. Move the shift lever into the PARK (P) position by
pulling the shift lever toward you and moving it up
as far as it will go.
3. If your vehicle has four-wheel drive, be sure the
transfer case is in a drive gear – not in
NEUTRAL (N).
4. Turn the ignition key to LOCK.
5. Remove the key and take it with you. If you can
leave your vehicle with the ignition key in your
hand, your vehicle is in PARK (P).
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Leaving Your Vehicle With the Engine
Running (Automatic Transmission)
{CAUTION:
It can be dangerous to leave your vehicle with
the engine running. Your vehicle could move
suddenly if the shift lever is not fully in
PARK (P) with the parking brake rmly set.
If you have four-wheel drive with a manual
transfer case shift lever and your transfer case
is in NEUTRAL, your vehicle will be free to roll,
even if your shift lever is in PARK (P). So be
sure the transfer case is in a drive gear — not
in NEUTRAL.
And, if you leave the vehicle with the engine
running, it could overheat and even catch re.
You or others could be injured. Do not leave
your vehicle with the engine running unless
you have to.If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and the
parking brake is rmly set before you leave it. After you
move the shift lever into PARK (P), hold the regular
brake pedal down. Then, see if you can move the shift
lever away from PARK (P) without rst pulling it
toward you. If you can, it means that the shift lever was
not fully locked into PARK (P).
Torque Lock (Automatic Transmission)
If you are parking on a hill and you do not shift your
transmission into PARK (P) properly, the weight of the
vehicle may put too much force on the parking pawl
in the transmission. You may nd it difficult to pull the
shift lever out of PARK (P). This is called “torque
lock.” To prevent torque lock, set the parking brake and
then shift into PARK (P) properly before you leave
the driver’s seat. To nd out how, see “Shifting
Into PARK (P)” listed earlier in this section.
When you are ready to drive, move the shift lever out of
PARK (P) before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some of the
pressure from the parking pawl in the transmission, so
you can pull the shift lever out of PARK (P).
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Parking Your Vehicle
(Manual Transmission)
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the manual
transmission is in gear. Your or someone else
could be seriously injured. Be sure to set the
parking brake before placing the transfer case
in NEUTRAL. SeeParking Brake on page 2-48
for more information.
Before you get out of your vehicle, move the shift lever
into REVERSE (R), and rmly apply the parking
brake. Once the shift lever has been placed into
REVERSE (R) with the clutch pedal pressed in, you can
turn the ignition key to LOCK, press the key release
button, remove the key and release the clutch.
If you are parking on a hill, or if you are pulling a trailer,
seeTowing a Trailer on page 4-68.
Parking Over Things That Burn
{CAUTION:
Things that can burn could touch hot exhaust
parts under your vehicle and ignite. Do not
park over papers, leaves, dry grass or other
things that can burn.
2-52

{CAUTION:
Four-wheel drive vehicles with the transfer
case in NEUTRAL will allow the vehicle to roll,
even if your automatic transmission shift lever
is in PARK (P). So, be sure the transfer case is
in a drive gear — not in NEUTRAL. Always set
your parking brake.
Follow the proper steps to be sure your vehicle will not
move. SeeShifting Into Park (P) (Automatic
Transmission) on page 2-49.
If you are pulling a trailer, seeTowing a Trailer on
page 4-68.
Mirrors
Manual Rearview Mirror
Pull or push the tab under the mirror to adust it to the
night or daytime setting. In the nightime setting, the glare
from headlamps behind the vehicle will be less intense.
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
Your vehicle may have this feature. When on, an
automatic dimming mirror automatically dims to the
proper level to minimize glare from lights behind
you after dark.
The mirror also includes a dual display in the upper
right corner of the mirror face. The compass reading and
the outside temperature will both appear in the display
at the same time.
P(On/Off):This is the on/off button.
2-55

Passenger Airbag Indicator
The vehicle may be equipped with a passenger airbag
indicator, on the mirror glass, just above the buttons.
If the vehicle has this feature, the mirror will display the
word ON, or an airbag symbol in Canada, when the
passenger airbag is enabled. For more information, see
Passenger Sensing System on page 1-76.
Cleaning the Mirror
When cleaning the mirror, use a paper towel or similar
material dampened with glass cleaner. Do not spray
glass cleaner directly on the mirror as that may cause
the liquid cleaner to enter the mirror housing.
Automatic Dimming Rearview Mirror
with Compass and Temperature
Display
If the vehicle is equipped with an automatic mirror, it
will, when on, automatically dim to the proper level
to minimize glare from lights behind you after dark.
The mirror also includes a display in the upper
right corner of the mirror face. The compass reading
and the outside temperature will both appear in
the display at the same time. The dual display can be
turned on or off by briey pressing either the TEMP
or the COMP button.
Temperature Display
The temperature can be displayed by pressing the
TEMP button. Pressing the TEMP button once briey,
will toggle the temperature reading on and off. To
alternate the temperature reading between Fahrenheit
and Celsius, press and hold the TEMP button for
approximately four seconds until the display blinks F
and C. Press and release the TEMP button to toggle
between the Fahrenheit and Celsius readings. After
approximately four seconds of inactivity, the display will
stop blinking and display the last selection made.
If an abnormal reading is displayed, for an extended
period of time, please consult your dealer. Under certain
circumstances, a delay in updating the temperature is
normal.
Automatic Dimming Mirror Operation
The time period you need to press and hold the TEMP
button to turn the automatic dimming feature on or
off is approximately eight seconds. The indicator light to
the left of the TEMP button will still turn on or off to
show you when the automatic dimming feature is
activated. Once the mirror is turned off, it will remain off
until it is turned back on, or until the vehicle is
restarted.
2-58