
Six-Speed (VORTEC™ 8.1L V8 and
DURAMAX®6.6L 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.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.
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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.
Shift Speeds
{CAUTION:
If you skip a gear when you downshift, you
could lose control of your vehicle. You could
injure yourself or others. Do not shift down
more than one gear at a time when you
downshift.Do not allow the engine rpm to overspeed and enter the
tachometer red lines. Engine overspeed occurs when
downshifting, or descending a grade, at too high a
vehicle speed. When going down steep grades, always
select a gear at least one position lower than you
would use on climbing a grade. This will allow the
vehicle’s engine to provide some braking and help to
slow the vehicle as it goes down the grade. Monitor your
vehicle speed, acceleration and engine rpm while
applying the brakes as you go down the grade to ensure
you have complete control over the vehicle.
If your engine speed drops below 600 rpm, or if the
engine is not running smoothly, you should downshift to
the next lower gear. When operating on slippery
surfaces, downshift at lower than normal vehicle speeds
to prevent the tires from slipping.
In bench seat equipped vehicles, move the tallest
beverage containers to the right cupholder to provide
additional clearance for the shift lever.
For vehicles equipped with a center console, the front
cup holder pulls out and turns 180° to provide additional
clearance between tall beverage containers and the
shift lever.
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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 Four-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.
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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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.
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.
Recommended Transfer Case Settings
Driving
ConditionsTransfer Case Settings
2
mAUTO
4WD4m4nN
Normal YES
Variable YES
Severe YES
Extreme YES
Vehicle
in Tow*YES
*SeeRecreational Vehicle Towing on page 4-62for
further information.
You can choose among four driving settings:
Notice:Driving on clean, dry pavement in
Four-Wheel-Drive High or Four-Wheel-Drive Low 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 High or
Four-Wheel-Drive Low for extended periods of time.
AUTO 4WD (Automatic Four-Wheel Drive):This
setting is ideal for use when road surface traction
conditions are variable. When driving your vehicle in
Automatic Four-Wheel Drive, the front axle is engaged,
but the vehicle’s power is sent to the rear wheels.
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Shifting into Four-Wheel High or AUTO
4WD (Automatic 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.
It is typical for your vehicle to exhibit signi cant
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.
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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).
Shifting Into NEUTRAL
{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 2-49.
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.
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4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to Two-Wheel High.
6. Simultaneously press and hold the Two-Wheel High
and Four-Wheel Low buttons for 10 seconds. The
red NEUTRAL light will come on when the
transfer case shift to NEUTRAL is complete.
7. If the engine is running, shift the transmission to
REVERSE (R) for one second, then shift the
transmission to DRIVE (D) for one second, or
FIRST (1) for vehicles equipped with a manual
transmission.
8. Turn the engine off, by turning the key to
ACCESSORY.
9. Place the transmission shift lever in PARK (P).
10. Turn the ignition to LOCK.Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular brake
pedal.
2. Turn the ignition to RUN with the engine off.
3. Shift the transmission to NEUTRAL (N).
4. Press the button for the desired transfer case shift
position (Two-Wheel High, Four-Wheel High, AUTO
4WD, or Four-Wheel Low).
5. After the transfer case has shifted out of NEUTRAL
the red light will go out.
6. Release the parking brake.
7. 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.
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Shifting into NEUTRAL
{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 2-49.
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. Press the foot brake pedal and put the transmission
in NEUTRAL (N).
4. Shift the transfer case to Two-Wheel High.
5. Simultaneously press and hold the Two-Wheel High
and Four-Wheel Low buttons for 10 seconds. The
red NEUTRAL light will come on when the
transfer case shift to NEUTRAL is complete.
6. Start the engine if it is not already running.7. Press and hold the foot brake pedal and Shift the
transmission to REVERSE (R) for one second,
then shift the transmission for one second to
DRIVE (D) for an automatic transmission, or
FIRST (1) for vehicles equipped with a manual
transmission and then let out the clutch. This is to
ensure the transfer case is in NEUTRAL. If not,
repeat this procedure starting at Step 3.
8. Turn the engine off, by turning the key to
ACCESSORY.
9. Place the transmission shift lever in PARK (P) for
an automatic transmission, or FIRST (1) for
vehicles equipped with a manual transmission.
10. Turn the ignition to LOCK.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and press and hold the
regular brake pedal.
2. Shift the transmission to NEUTRAL (N) for an
automatic transmission, or press the clutch pedal for
vehicles equipped with a manual transmission.
Then turn the ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (Two-Wheel High, Four-Wheel High, or
Four-Wheel Low).
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