2005 CHEVROLET SILVERADO light

Grade braking is active and automatic both in Tow/Haul
mode and normal shift mode. Grade braking is more
aggressive when in Tow/Haul mode and can
automatically downshift to SECOND (2), which is
different than grade braking while in normal shift mode
where automatic downshifts are limited to FOURTH (4).
The tachometer for both the diesel and gasoline
engine shows a dashed red zone and a solid red zone.
The dashed red zone indicates where a transmission
shift occurs for full engine power. When using grade
braking, the transmission’s shift point is adjusted to just
prior to the solid red zone, providing the benet of
additional engine braking.
Grade braking driving within the dashed red zone is
normal, both the diesel and gasoline engine have been
designed for this grade braking feature. Do not allow
the engine to go into the solid red zone. Apply the
vehicle’s brakes for a short time to slow down if you are
driving on a long hill and the tachometer needle
enters the solid red zone. SeeTowing a Trailer on
page 4-69for more information.Overdrive Disable
(Allison®Transmission Only)
If your vehicle has an Allison Transmission®, you may
have the overdrive disable feature. The overdrive disable
feature prevents the transmission from shifting into
FIFTH (5) gear. The selector button is located on the
end of the column shift lever. You can turn overdrive
disable on and off by pressing and holding the button at
the end of the column shift lever until the indicator
light, on the instrument panel, illuminates.
If your vehicle has both Tow/Haul and overdrive disable,
tap the button once to enable or disable Tow/Haul,
and press and hold the button to enable or disable
overdrive disable.
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During the rst 500 miles (805 km) of vehicle use,
start the vehicle moving in FIRST (1) gear. This allows
the clutch components to wear-in properly.
FIRST (1):With the vehicle at a stop, release the
brake, press the clutch pedal and shift into FIRST (1).
Then, slowly let up on the clutch pedal as you press
the accelerator pedal. Only downshift into FIRST (1)
when the vehicle has come to a complete stop. If the
shift lever will not go into FIRST (1), put the lever
in NEUTRAL and let up on the clutch pedal to fully
engage the clutch. Press the clutch pedal again.
Then, shift into FIRST (1).
SECOND (2):With the vehicle at a stop, release the
brake, press the clutch pedal and shift into SECOND (2).
Then, slowly let up on the clutch pedal as you press
the accelerator pedal. With the vehicle moving, press the
clutch pedal and upshift into SECOND (2) from
FIRST (1) while applying light pressure to the right on
the shifter. Then, slowly let up on the clutch pedal
as you press the accelerator pedal. If you come to a
complete stop and the shift lever will not go into
SECOND (2), put the lever in NEUTRAL and let up on
the clutch pedal to fully engage the clutch. Press
the clutch pedal again. Then, shift into SECOND (2).THIRD (3):Press the clutch pedal and upshift into
THIRD (3). Then, slowly let up on the clutch pedal as
you press the accelerator pedal.
FOURTH (4), FIFTH (5) and SIXTH (6):Upshift into
the higher forward gears the same way as you do
THIRD (3). Slowly let up on the clutch pedal as you
press the accelerator pedal.
NEUTRAL:Use this position when you start or idle
your engine.
REVERSE (R):To back up, press the clutch pedal.
Wait for the vehicle to stop moving and then, shift
to REVERSE (R). Let up on the clutch slowly while
pressing the accelerator pedal. Also, use REVERSE (R),
along with the parking brake, when turning off your
engine and parking your vehicle.
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Up-Shift Light
If you have a manual
transmission, you may
have a shift light. This light
will show you when to
shift to the next higher gear
for best fuel economy.
When this light comes on, you can shift to the next
higher gear if weather, road and traffic conditions allow.
For the best fuel economy, accelerate slowly and
shift when the light comes on.
While you accelerate, it is normal for the light to go on
and off if you quickly change the position of the
accelerator.
If your vehicle has four-wheel drive and is equipped with
a manual transmission, disregard the SHIFT light
when the transfer case is in 4-Wheel Low.
Ignore the SHIFT light when you downshift.
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. See the appropriate text for the transfer case in
your vehicle.
Notice:Driving on clean, dry pavement in
four-wheel drive for an extended period of time may
cause premature wear on your vehicle’s powertrain.
Do not drive on clean, dry pavement in four-wheel
drive for extended periods of time.
Front Axle Locking Feature
The front axle locks and unlocks automatically when
you shift the transfer case. Some delay for the axle to
lock or unlock is normal.
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Manual Transfer Case
The transfer case shift lever is on the oor to the right
of the driver. Use this lever to shift into and out of
four-wheel drive.
A 4WD indicator light
comes on when you shift
into four-wheel drive
and the front axle engages.
SeeFour-Wheel-Drive
Light on page 3-48.
Some delay between shifting and when the indicator
light comes on is normal.
Recommended Transfer Case Settings
Driving ConditionsTransfer Case Settings
2H 4H 4L N
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*SeeRecreational Vehicle Towing on page 4-63or
Towing Your Vehicle on page 4-63for further
information.
An indicator light near the lever shows you the transfer
case settings:
4L (Four-Wheel Low):This setting also engages your
front axle and delivers extra torque. You may never need
four-wheel low. It sends maximum power to all four
wheels. You might choose four-wheel low if you are
driving off-road in deep sand, deep mud, deep snow, and
while climbing or descending steep hills. When operating
in Four-Wheel Low, the gear ratio provides additional
torque when compared to four-wheel high. The
transmission gear shift feel will be exaggerated.
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Shifting from 2H (Two-Wheel High) to
4H (Four-Wheel High)

Shifts between 2H and 4H 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 4H or 2H position.
In extremely cold weather, it may be necessary to
slow or stop the vehicle to shift into four-wheel high
until your vehicle has warmed up.
While in 4H, your vehicle can be driven at any posted
legal speed limit.
Shifting In or Out of 4L (Four-Wheel Low)
Notice:Shifting the transfer case into four-wheel
low 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 four-wheel low while
the vehicle is moving faster than 3 mph (5 km/h).Shifts into 4L 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 4L position.
When in 4L 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 position.
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You can choose among four driving settings:
AUTO 4WD:This setting is ideal for use when road
surface traction conditions are variable. When driving
your vehicle in AUTO four-wheel drive, the front axle is
engaged, but the vehicle’s power is sent to the rear
wheels. When the vehicle detects a loss of traction, the
system will automatically engage four-wheel drive.
Driving in this mode results in slightly lower fuel
economy than Two-Wheel High.
2
m(Two-Wheel High):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.
{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 2-51.
N (NEUTRAL):Shift the vehicle’s transfer case to
N (NEUTRAL) only when towing your vehicle.
SeeRecreational Vehicle Towing on page 4-63or
Towing Your Vehicle on page 4-63for more information.
4
m(Four-Wheel High):Use this setting 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.
4
n(Four-Wheel Low):This setting also engages your
front axle and delivers extra torque. You may never need
Four-Wheel Low. It sends maximum power to all four
wheels. You might choose Four-Wheel Low if you are
driving off-road in deep sand, deep mud, deep snow, and
while climbing or descending steep hills. When operating
in Four-Wheel Low, the gear ratio provides additional
torque when compared to four-wheel high. The
transmission gear shift feel will be exaggerated.
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.
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It will stay on 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. SeeDIC
Warnings and Messages on page 3-54for further
information.
Shifting into Four-Wheel High or
AUTO 4WD (AUTO Four-Wheel Drive)
Press and release the four-wheel high or AUTO 4WD
switch. This can be done at any speed, except
when shifting from Four-Wheel Low, and the indicator
light will ash while shifting. It will remain on when
the shift is completed.
Shifting into Two-Wheel High
Press and release the Two-Wheel High switch.
This can be done at any speed, except when shifting
from Four-Wheel Low.
Shifting into Four-Wheel Low
Notice:Shifting the transfer case into four-wheel
low 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 four-wheel low while
the vehicle is moving faster than 3 mph (5 km/h).
To shift to Four-Wheel Low, the ignition must be in RUN
and the vehicle must be stopped or moving less than
3 mph (5 km/h) with the transmission in NEUTRAL (N).
The preferred method for shifting into four-wheel low
is to have your vehicle moving 1 to 2 mph (1.6 to
3.2 km/h). Press and release the Four-Wheel Low
switch. You must wait for the Four-Wheel Low indicator
light to stop ashing and remain on before shifting
your transmission in gear.
Notice:Shifting the transmission into gear before
the Four-Wheel Low indicator light has stopped
ashing could damage the transfer case. To help
avoid damaging your vehicle, always wait for
the Four-Wheel Low indicator light to stop ashing
before shifting the transmission into gear.
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It is typical for your vehicle to exhibit signicant
engagement noise and bump when shifting between
Four-Wheel Low and Four-Wheel High ranges or from
NEUTRAL (N) with the engine running.
If the Four-Wheel Low switch is pressed when your
vehicle is in gear and/or moving, the Four-Wheel Low
indicator light will ash for 30 seconds and not complete
the shift unless your vehicle is moving less than
3 mph (5 km/h) and the transmission is in NEUTRAL (N).
After 30 seconds the transfer case will shift to
four-wheel high mode.
Shifting Out of Four-Wheel Low
To shift from Four-Wheel Low to Four-Wheel High,
AUTO 4WD, or Two-Wheel High, your vehicle must be
stopped or moving less than 3 mph (5 km/h) with
the transmission in NEUTRAL (N) and the ignition in
RUN. The preferred method for shifting out of
Four-Wheel Low is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Press and release the
Four-Wheel High, AUTO 4WD, or Two-Wheel High
switch. You must wait for the Four-Wheel High,
AUTO 4WD, or Two-Wheel High indicator light to stop
ashing and remain on before shifting your transmission
into gear.Notice:Shifting the transmission into gear before
the Four-Wheel Low indicator light has stopped
ashing could damage the transfer case. To help
avoid damaging your vehicle, always wait for
the Four-Wheel Low indicator light to stop ashing
before shifting the transmission into gear.
The transfer case may make noise and the vehicle
may jerk when the transfer case is shifted between
Four-Wheel Low and Four-Wheel High ranges or from
NEUTRAL with the engine running.
If the four-wheel high, AUTO 4WD, or Two-Wheel High
switch is pressed when your vehicle is in gear and/or
moving, the Four-Wheel High, AUTO 4WD, or
Two-Wheel High indicator light will ash for 30 seconds
but will not complete the shift unless your vehicle is
moving less than 3 mph (5 km/h) and the transmission
is in NEUTRAL (N).
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