2001 GMC SIERRA engine

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Tow/Haul Mode Selector Switch
(Automatic Transmission)
Your vehicle is equipped with a tow/haul mode. The
selector switch is located on the end of the column shift
lever. You can use this feature to assist when towing or
hauling a heavy load. See ªTow/Haul Modeº in the
Index for more information.
Manual Transmission Operation
5-Speed (VORTEC 6000 V8 Engine)
Here's 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 first 500 miles (805 km) of vehicle use, start
your vehicle moving in FIRST (1). This allows clutch
components to break
-in properly.

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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're going less
than 20 mph (32 km/h). If you've come to a complete
stop and it's 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.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, first 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:
Shift to REVERSE (R) only after your vehicle is
stopped. Shifting to REVERSE (R) while your
vehicle is moving could damage your transmission.
Also, use REVERSE (R), along with the parking brake,
when turning off your engine and parking your vehicle.

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5-Speed
(VORTEC 4300 V6 and 4800 V8 Engines)
Here's 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're going less
than 20 mph (32 km/h). If you've come to a complete
stop and it's 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.NEUTRAL: Use this position when you start or idle
your engine.
REVERSE (R): To back up, first 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:
Shift to REVERSE (R) only after your vehicle is
stopped. Shifting to REVERSE (R) while your
vehicle is moving could damage your transmission.
Also, use REVERSE (R), along with the parking brake,
when turning off your engine and parking your vehicle.

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6-Speed
(VORTEC 8100 V8 and DURAMAX

6600 V8 Engines)
Here's how to operate
your transmission.
This 6
-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 first 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).

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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.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.

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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.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.

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Four-Wheel Drive (If Equipped)
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 in the 4-WHEEL HIGH (4HI) or
4
-WHEEL LOW (4LO) positions for a long time
on dry or wet pavement could shorten the life of
your vehicle's drivetrain.
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 (If Equipped)
The transfer case shift lever is on the floor to the right of the
driver. Use this lever to shift into and out of four
-wheel drive.
The 4WD indicator will
light up when you shift into
four
-wheel drive and the
front axle engages.
Some delay between shifting and the indicator's lighting
is normal.

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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 flash 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 to NEUTRAL
To shift the transfer case to NEUTRAL, first 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. Connect the vehicle to the towing vehicle.
4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to 2HI.
6. 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.7. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second.
8. Turn the ignition to OFF.
9. Place the transmission shift lever in PARK (P).
10. Release the parking brake prior to towing.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular
brake pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (2HI, 4HI, AUTO 4WD or 4LO).
4. After the transfer case has shifted out of NEUTRAL
the red light will go out.
5. You may start the engine and shift the transmission
to the desired position.