2006 GMC SIERRA manual transmission

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.
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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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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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Parking on Hills
{CAUTION:
You really should not park your vehicle, with
a trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet for an automatic transmission,
or into gear for a manual transmission.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P) for an
automatic transmission, or REVERSE (R) for
a manual transmission.
5. If you have a four-wheel-drive vehicle, be sure the
transfer case is in a drive gear and not in NEUTRAL.
6. Release the regular brakes.
{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.
Always put the shift lever fully in PARK (P) with
the parking brake rmly set.
If the transfer case on four-wheel-drive vehicles
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.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine
Shift into a gear
Release the parking brake
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. SeeScheduled Maintenance (Gasoline
Engine) on page 6-4for more information. Things that
are especially important in trailer operation are automatic
transmission uid (don’t overll), engine oil, axle
lubricant, belt, cooling system and brake system. Each of
these is covered in this manual, and the Index will help
you nd them quickly. If you’re trailering, it’s a good idea
to review these sections before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
Your vehicle is equipped with one of the following wiring
harnesses for towing a trailer or hauling a slide-in
camper.
Basic Trailer Wiring
All regular, extended cab and crew cab pickups have an
eight-wire trailer towing harness.
For vehicles not equipped with heavy duty trailering, the
harness is clipped to the vehicle’s frame behind the spare
tire mount. The harness requires the installation of a
trailer connector, which is available through your dealer.
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