2005 GMC SIERRA engine

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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Shift Speeds
{CAUTION:
If you skip a gear when you downshift, you
could lose control of your vehicle. You could
injure yourself or others. Don’t 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.
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.
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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 on pavement 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.
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.
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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.
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.
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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 signicant
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 signicant
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).
Shifting into NEUTRAL
To shift the transfer case to NEUTRAL do the following:
1. Start the vehicle or turn the ignition to RUN.
2. Put the transmission in NEUTRAL (N).
3. Shift the transfer case to 2HI.
4. 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.
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5. 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.
6. Turn the ignition to LOCK.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
2. Press the button for the desired transfer case shift
position (2HI, 4HI, AUTO 4WD or 4LO).
3. After the transfer case has shifted out of NEUTRAL
the red light will go out.
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.
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.
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Shifting into NEUTRAL
To shift the transfer case to NEUTRAL, rst make sure
the vehicle is parked so that it will not roll:
1. Start the vehicle or turn the ignition to RUN.
2. Put the transmission in NEUTRAL (N).
3. Shift the transfer case to 2HI.
4. 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.
5. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second, for FIRST (1) for vehicles equipped
with a manual transmission.
6. Turn the ignition to LOCK.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
2. Press the button for the desired transfer case shift
position (2HI, 4HI, or 4LO).
3. After the transfer case has shifted out of NEUTRAL
the red light will go out.
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 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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