transmission GMC SIERRA 2006 Manual PDF

{CAUTION:
Coasting downhill in NEUTRAL (N) or with the
ignition off is dangerous. Your brakes will have
to do all the work of slowing down. They could
get so hot that they would not work well. You
would then have poor braking or even none
going down a hill. You could crash. Always
have your engine running and your vehicle
in gear when you go downhill.
Know how to go down hills. The most important
thing to know is this: let your engine do some of
the slowing down. Shift to a lower gear when you
go down a steep or long hill.
Know how to go uphill. You may want to shift down
to a lower gear. The lower gears help cool your
engine and transmission, and you can climb the hill
better.
Stay in your own lane when driving on two-lane
roads in hills or mountains. Do not swing wide
or cut across the center of the road. Drive at
speeds that let you stay in your own lane.
As you go over the top of a hill, be alert. There
could be something in your lane, like a stalled car
or an accident.
You may see highway signs on mountains that warn
of special problems. Examples are long grades,
passing or no-passing zones, a falling rocks area, or
winding roads. Be alert to these and take appropriate
action.
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If Your Vehicle is Stuck in Sand,
Mud, Ice or Snow
In order to free your vehicle when it is stuck, you will
need to spin the wheels, but you do not want to spin your
wheels too fast. The method known as rocking can help
you get out when you are stuck, but you must use
caution.
{CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured.
And, the transmission or other parts of the
vehicle can overheat. That could cause an
engine compartment re or other damage.
When you are stuck, spin the wheels as little
as possible. Do not spin the wheels above
35 mph (55 km/h) as shown on the
speedometer.Notice:Spinning your wheels can destroy parts
of your vehicle as well as the tires. If you spin the
wheels too fast while shifting your transmission
back and forth, you can destroy your transmission.
For more information about using tire chains on your
vehicle, seeTire Chains on page 5-89.
Rocking Your Vehicle to Get It Out
First, turn your steering wheel left and right. That
will clear the area around your front wheels. If you have
a four-wheel-drive vehicle, shift into Four-Wheel
High. If your vehicle has the traction assist system, you
should turn it off by pressing the TAS on/off button.
Then shift back and forth between REVERSE (R) and a
forward gear, or with a manual transmission, between
FIRST (1) or SECOND (2) and REVERSE (R), spinning
the wheels as little as possible. Release the accelerator
pedal while you shift, and press lightly on the
accelerator pedal when the transmission is in gear. By
slowly spinning your wheels in the forward and
reverse directions, you will cause a rocking motion that
may free your vehicle. If that does not get you out
after a few tries, you may need to be towed out. Or, you
can use your recovery hooks if your vehicle has
them. If you do need to be towed out, seeTowing Your
Vehicle on page 4-62.
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Towing
Towing Your Vehicle
Consult your dealer or a professional towing service
if you need to have your disabled vehicle towed.
SeeRoadside Assistance Program on page 7-6.
If you want to tow your vehicle behind another vehicle
for recreational purposes (such as behind a motorhome),
see “Recreational Vehicle Towing” following.
Recreational Vehicle Towing
Recreational vehicle towing means towing your vehicle
behind another vehicle – such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as dinghy towing, towing your vehicle
will all four wheels on the ground, and dolly towing,
towing your vehicle with two wheels on the ground
and two wheels up on a device known as a “dolly”.
With the proper preparation and equipment, many
vehicles can be towed in these ways. See “Dinghy
Towing” and “Dolly Towing” following.Here are some important things to consider before you
do recreational vehicle towing:
What’s the towing capacity of the towing vehicle?
Be sure you read the tow vehicle manufacturer’s
recommendations.
How far will you tow? Some vehicles have
restrictions on how far and how long they can tow.
Do you have the proper towing equipment? See your
dealer or trailering professional for additional advice
and equipment recommendations.
Is your vehicle ready to be towed? Just as you would
prepare your vehicle for a long trip, you’ll want to
make sure your vehicle is prepared to be towed.
SeeBefore Leaving on a Long Trip on page 4-38.
Dinghy Towing
Two-Wheel-Drive Vehicles
Notice:If you tow your vehicle with all four wheels
on the ground, the drivetrain components could be
damaged. The repairs would not be covered by your
warranty. Do not tow your vehicle with all four wheels
on the ground.
Two-wheel-drive vehicles should not be towed
with all four wheels on the ground. Two-wheel-drive
transmissions have no provisions for internal lubrication
while being towed.
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Four-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle:
1. Shift an automatic transmission to PARK (P), or a
manual transmission to FIRST (1).
2. Turn the engine off, but leave the ignition on.
3. Firmly set the parking brake.
4. Securely attach the vehicle being towed to the tow
vehicle.
{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle to
roll even if the transmission is in PARK (P) for
an automatic transmission, or if your vehicle
is in gear, for a manual transmission. You or
others could be injured. Make sure the parking
brake is rmly set before you shift the transfer
case to NEUTRAL.
5. Shift the transfer case to NEUTRAL. See
Four-Wheel Drive on page 2-38for the proper
procedure to select the neutral position for
your vehicle.
6. Release the parking brake only after the vehicle
being towed is rmly attached to the towing vehicle.
7. Turn the ignition off and leave the steering column
unlocked.
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Dolly Towing
Front Towing (Front Wheels
Off the Ground)
Two-Wheel-Drive Vehicles
Notice:If you tow a two-wheel-drive vehicle with the
rear wheels on the ground, the transmission could be
damaged. The repairs would not be covered by your
warranty. Never tow your vehicle with the rear wheels
on the ground.
Two-wheel-drive vehicles should not be towed
with the rear wheels on the ground. Two-wheel-drive
transmissions have no provisions for internal lubrication
while being towed.
To dolly tow a two-wheel-drive vehicle, you must tow
the vehicle with the rear wheels on the dolly. See “Rear
Towing (Rear Wheels Off the Ground)” later in this
section for more information.
Four-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle:
1. Drive the vehicle up onto the tow dolly.
2. Shift an automatic transmission to PARK (P), or a
manual transmission to FIRST (1).
3. Turn the engine off, but leave the ignition on.
4. Firmly set the parking brake.
5. Securely attach the vehicle being towed to the
tow dolly.
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{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle to
roll even if the transmission is in PARK (P) for
an automatic transmission, or if your vehicle
is in gear, for a manual transmission. You or
others could be injured. Make sure the parking
brake is rmly set before you shift the transfer
case to NEUTRAL.
6. Shift the transfer case to NEUTRAL. See
Four-Wheel Drive on page 2-38for the proper
procedure to select the neutral position for
your vehicle.
7. Release the parking brake only after the vehicle
being towed is rmly attached to the towing vehicle.
8. Turn the ignition off and lock the steering column.
Rear Towing (Rear Wheels
Off the Ground)
Two-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle from
the rear:
1. Drive the vehicle onto the dolly.
2. Firmly set the parking brake. SeeParking Brake on
page 2-52
3. Put an automatic transmission in PARK (P) or a
manual transmission in FIRST (1).
4. Follow the dolly manufacturer’s instructions to
attach and secure the vehicle being towed to
the dolly and then the loaded dolly to the tow
vehicle. Make sure the wheels are straight before
towing.
For manual transmission vehicles, make sure the
wheels are straight before proceeding to the next
steps. On automatic transmission vehicles, use an
adequate clamping device to ensure that the front
wheels are locked into the straight position.
5. Release the parking brake only after the vehicle
being towed is rmly attached to the tow vehicle.
6. Turn the ignition to LOCK.
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Four-Wheel-Drive Vehicles
Use the following procedure to tow your vehicle from
the rear:
1. Drive the vehicle onto the dolly.
2. Firmly set the parking brake. SeeParking Brake on
page 2-52
3. Put an automatic transmission in PARK (P) or a
manual transmission in FIRST (1).
4. Follow the dolly manufacturer’s instructions to
attach and secure the vehicle being towed to
the dolly and then the loaded dolly to the tow
vehicle.
For manual transmission vehicles, make sure the
wheels are straight before proceeding to the next
steps. On automatic transmission vehicles, use an
adequate clamping device to ensure that the front
wheels are locked into the straight position.{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle to
roll even if the transmission is in PARK (P) for
an automatic transmission, or if your vehicle
is in gear, for a manual transmission. You or
others could be injured. Make sure the parking
brake is rmly set before you shift the transfer
case to NEUTRAL.
5. Shift the transfer case to NEUTRAL.
SeeFour-Wheel Drive on page 2-38
6. Release the parking brake only after the vehicle
being towed is rmly attached to the tow vehicle.
7. Turn the ignition to LOCK.
4-66

If You Do Decide To Pull A Trailer
If you do, here are some important points:
There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will be legal, not only where you live but also
where you’ll be driving. A good source for this
information can be state or provincial police.
Consider using a sway control. See “Hitches” later in
this section.
Don’t tow a trailer at all during the rst
500 miles (800 km) your new vehicle is driven.
Your engine, axle or other parts could be damaged.
Then, during the rst 500 miles (800 km) that you tow
a trailer, don’t drive over 50 mph (80 km/h) and don’t
make starts at full throttle. This helps your engine
and other parts of your vehicle wear in at the heavier
loads.
If you have an automatic transmission, you can tow
in DRIVE (D). You may want to shift the transmission
to THIRD (3) or, if necessary, a lower gear selection
if the transmission shifts too often, such as under
heavy loads and/or hilly conditions. If you have a
manual transmission and you are towing a trailer,
it’s better not to use the highest gear. SeeTow/Haul
Mode Light on page 3-50.Three important considerations have to do with weight:
The weight of the trailer
The weight of the trailer tongue
The weight on your vehicle’s tires
Tow/Haul Mode
Tow/Haul is a feature on automatic transmission
equipped vehicles that assists when pulling a heavy
trailer or a large or heavy load. SeeTow/Haul Mode
on page 2-31for more information.
Tow/Haul is designed to be most effective when the
vehicle and trailer combined weight is at least 75 percent
of the vehicle’s Gross Combined Weight Rating (GCWR).
See “Weight of the Trailer” later in the section. Tow/Haul
is most useful under the following driving conditions:
When pulling a heavy trailer or a large or heavy load
through rolling terrain.
When pulling a heavy trailer or a large or heavy load
in stop and go traffic.
When pulling a heavy trailer or a large or heavy load
in busy parking lots where improved low speed
control of the vehicle is desired.
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Operating the vehicle in Tow/Haul when lightly loaded
or with no trailer at all will not cause damage. However,
there is no benet to the selection of Tow/Haul when the
vehicle is unloaded. Such a selection when unloaded
may result in unpleasant engine and transmission driving
characteristics and reduced fuel economy. Tow/Haul is
recommended only when pulling a heavy trailer or a large
or heavy load.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For example,
speed, altitude, road grades, outside temperature and
how much your vehicle is used to pull a trailer are all
important. It can also depend on any special equipment
that you have on your vehicle, and the amount of tongue
weight the vehicle can carry. See “Weight of the Trailer
Tongue” later in this section for more information.Maximum trailer weight is calculated assuming only the
driver is in the tow vehicle and it has all the required
trailering equipment. The weight of additional optional
equipment, passengers and cargo in the tow vehicle
must be subtracted from the maximum trailer weight.
Above the 5,000 lb (2 268 kg) trailer rating, the
handling/trailering suspension is required on
C-1500 models and the handling/trailering or
off-road suspension is required on K-1500 models.
Use one of the following charts to determine how much
your vehicle can weigh, based upon your vehicle model
and options.
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Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns than
normal. Do this so your trailer won’t strike soft shoulders,
curbs, road signs, trees or other objects. Avoid jerky or
sudden maneuvers. Signal well in advance.
Turn Signals When Towing a Trailer
The arrows on your instrument panel will ash whenever
you signal a turn or lane change. Properly hooked up, the
trailer lamps will also ash, telling other drivers you’re
about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ash for turns even if the bulbs on the trailer are
burned out. Thus, you may think drivers behind you are
seeing your signal when they are not. It’s important to
check occasionally to be sure the trailer bulbs are still
working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift down,
you might have to use your brakes so much that they
would get hot and no longer work well.If you have an automatic transmission, you can tow
in DRIVE (D). You may want to shift the transmission to
a lower gear selection if the transmission shifts too
often (e.g., under heavy loads and/or hilly conditions).
You may also want to activate the tow/haul mode if
the transmission shifts too often. SeeTow/Haul Mode
Light on page 3-50.
If you have a 5-speed manual transmission and you are
towing a trailer, it’s better not to use FIFTH (5) gear.
Just drive in FOURTH (4) gear (or, as you need to, a
lower gear).
If you have a 6-speed manual transmission and you are
towing a trailer, it’s better not to use SIXTH (6) gear.
Drive in FIFTH (5) gear (or, as you need to, a lower gear).
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant at or near sea level
will boil at a lower temperature than at higher altitudes.
If you turn your engine off immediately after towing at
high altitude on steep uphill grades, your vehicle may
show signs similar to engine overheating. To avoid this,
let the engine run while parked, preferably on level
ground, with the automatic transmission in PARK (P) for
at least ve minutes before turning the engine off. For
manual transmissions, let the engine run while parked,
preferably on level ground, with the transmission out
of gear and the parking brake applied, for at least ve
minutes before turning the engine off. If you do get the
overheat warning, seeEngine Overheating on page 5-37.
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