transmission CHEVROLET SILVERADO 2005 1.G User Guide

THIRD (3):This position is also used for normal driving,
however it offers more power and lower fuel economy
than DRIVE (D).
SECOND (2):This position gives you more power but
lower fuel economy. You can use SECOND (2) on
hills. It can help control your speed as you go down
steep mountain roads, but then you would also want to
use your brakes off and on.
If you manually select SECOND (2) in a light duty
automatic transmission, the transmission will drive in
second gear. You may use this feature for reducing the
speed of the rear wheels when you are trying to start
your vehicle from a stop on slippery road surfaces.
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 will not shift into rst
gear until the vehicle is going slowly enough.Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator
pedal may damage the transmission. If you are
stuck, do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.
On cold days, approximately 32°F (0°C) or colder,
your transmission is designed to shift differently.
The transmission uses a warm-up mode shift schedule
until the engine reaches normal operating temperature.
While the transmission is in warm-up mode it is
normal for transmission upshifts to be delayed or held
longer. This feature improves heater performance
by giving quicker vehicle warm-ups.
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Tow/Haul Mode
If your vehicle has an automatic transmission, it may be
equipped with a Tow/Haul mode. The selector button
is located on the end of the column shift lever. You can
use this feature to assist when towing or hauling a
heavy load. Turn Tow/Haul on and off by pressing the
button until the Tow/Haul indicator light illuminates
on the instrument panel.Tow/Haul is a feature on automatic transmission
equipped vehicles that assists when pulling a heavy
trailer or large or heavy load. Tow/Haul mode adjusts
the transmission’s shift pattern to reduce shift cycling,
providing increased performance, vehicle control,
and transmission cooling when towing or hauling
heavy loads.
If your vehicle is equipped with an Allison
®transmission,
you may have both Tow/Haul mode and overdrive
disable. See “Tow/Haul Mode” underTowing a Trailer
on page 4-69for more information.
Grade Braking
(Allison Transmission®Only)
Grade braking uses the engine and transmission to
slow a loaded vehicle on hills in addition to using the
brakes, saving on brake wear and increasing vehicle
stability. The Allison Transmission
®, when sensing
the driver’s desire to slow down while driving
downhill, will automatically shift to the next lower
gear range to assist in slowing down the vehicle.
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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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Manual Transmission Operation
Five-Speed (VORTEC™ 6000 V8 Engine)
Here is how to operate
your transmission.
FIRST (1) is intended only for heavy loads or trailer
towing and is not recommended for normal driving.
During the rst 500 miles (805 km) of vehicle use, start
your vehicle moving in FIRST (1). This allows clutch
components to break-in properly.FIRST (1):Press the clutch pedal and shift into
FIRST (1). Then, slowly let up on the clutch pedal as
you press the accelerator pedal. Shift into FIRST (1)
only when the vehicle is below 5 mph (8 km/h). If you
try to shift down into FIRST (1) at excessive vehicle
speeds, the shift lever will not move into FIRST (1) until
vehicle speed is reduced.
SECOND (2):Press the clutch pedal and shift into
SECOND (2). Then, slowly let up on the clutch pedal as
you press the accelerator pedal.
You can shift into SECOND (2) when you are going less
than 20 mph (32 km/h). If you have come to a complete
stop and it is hard to shift into SECOND (2), put the
shift lever into NEUTRAL and let up on the clutch.
Press the clutch pedal back down. Then shift into
SECOND (2). If you try to downshift into SECOND (2) at
excessive vehicle speeds, the shift lever will not move
into the SECOND (2) position until the vehicle speed
is reduced.
THIRD (3):Press the clutch pedal and shift into
THIRD (3). Then, slowly let up on the clutch pedal as
you press the accelerator pedal.
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FOURTH (4) and FIFTH (5):Shift into the higher
forward gears the same way you do for THIRD (3).
Slowly let up on the clutch pedal as you press the
accelerator pedal.
To stop, let up on the accelerator pedal and press the
brake pedal. Just before the vehicle stops, press
the clutch pedal and the brake pedal, and shift to
NEUTRAL.
NEUTRAL:Use this position when you start or idle
your engine.
REVERSE (R):To back up, rst press down the clutch
pedal. Wait for the vehicle to stop moving and then,
shift into REVERSE (R). Let up on the clutch pedal
slowly while pressing the accelerator pedal.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage the transmission.
The repairs would not be covered by your warranty.
Shift to REVERSE (R) only after your vehicle is
stopped.
Also, use REVERSE (R), along with the parking brake,
when turning off your engine and parking your vehicle.Five-Speed (VORTEC™ 4300 V6 and
4800 V8 Engines)
Here is how to operate your transmission:
FIRST (1):Press the clutch pedal and shift into
FIRST (1). Then, slowly let up on the clutch pedal as
you press the accelerator pedal.
You can shift into FIRST (1) when you are going less
than 20 mph (32 km/h). If you have come to a complete
stop and it is hard to shift into FIRST (1), put the shift
lever into NEUTRAL and let up on the clutch. Press the
clutch pedal back down. Then shift into FIRST (1).
SECOND (2):Press the clutch pedal as you let up on
the accelerator pedal and shift into SECOND (2).
Then, slowly let up on the clutch pedal as you press the
accelerator pedal.
THIRD (3), FOURTH (4) and FIFTH (5):Shift into
THIRD (3), FOURTH (4) and FIFTH (5) the same way
you do for SECOND (2). Slowly let up on the clutch
pedal as you press the accelerator pedal.
To stop, let up on the accelerator pedal and press the
brake pedal. Just before the vehicle stops, press
the clutch pedal and the brake pedal, and shift to
NEUTRAL.
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NEUTRAL:Use this position when you start or idle
your engine.
REVERSE (R):To back up, rst press down the clutch
pedal. Wait for the vehicle to stop moving and then,
shift into REVERSE (R). Let up on the clutch pedal
slowly while pressing the accelerator pedal.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage the transmission.
The repairs would not be covered by your warranty.
Shift to REVERSE (R) only after your vehicle is
stopped.
Also, use REVERSE (R), along with the parking brake,
when turning off your engine and parking your
vehicle.Six-Speed (VORTEC™ 8100 V8 and
DURAMAX®6600 V8 Engines)
Here is how to operate
your transmission.
This six-speed pattern is unique to GM manual
transmissions. The transmission always repositions the
shift lever to NEUTRAL, which is located between
FOURTH (4) and FIFTH (5) gear.
To prevent unintentional gear selections, additional
force is required to move the shift lever into
REVERSE (R) or FIRST (1). Use FIRST (1) when trailer
towing, driving with payload in the pickup box or
launching on a grade. Otherwise, start in SECOND (2)
gear. Only shift into FIRST (1) when the vehicle has
stopped moving.
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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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{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. SeeParking Brake on page 2-51.
N (Neutral):Shift to this setting only when your vehicle
needs to be towed. SeeRecreational Vehicle Towing
on page 4-63orTowing Your Vehicle on page 4-63.
2H (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.4H (Four-Wheel High):Use this setting 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.
You can shift from 2H to 4H or 4H high to 2H 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 four-wheel high.
When Using the Manual Transfer Case

Shifting should be made using quick motions.
Shifting slowly may make it more difficult to shift.
You may notice that it is harder to shift when the
vehicle is cold. After the vehicle warms up the
shifting will return to normal.
While in 4H or 4L you may experience reduced
fuel economy.
Avoid driving in four-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.
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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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