2005 GMC SIERRA four wheel drive

Highway Hypnosis
Is there actually such a condition as highway hypnosis?
Or is it just plain falling asleep at the wheel? Call it
highway hypnosis, lack of awareness, or whatever.
There is something about an easy stretch of road with
the same scenery, along with the hum of the tires on the
road, the drone of the engine, and the rush of the
wind against the vehicle that can make you sleepy. Do
not let it happen to you! If it does, your vehicle can
leave the road in less than a second, and you could
crash and be injured.
What can you do about highway hypnosis? First, be
aware that it can happen.
Then here are some tips:
Make sure your vehicle is well ventilated, with a
comfortably cool interior.
Keep your eyes moving. Scan the road ahead and
to the sides. Check your mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest,
service, or parking area and take a nap, get some
exercise, or both. For safety, treat drowsiness
on the highway as an emergency.
Hill and Mountain Roads
Driving on steep hills or mountains is different from
driving in at or rolling terrain.
If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that can make
your trips safer and more enjoyable. SeeOff-Road
Driving with Your Four-Wheel-Drive Vehicle on
page 4-20for information about driving off-road.
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If You Are 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 5-90.
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 4HI. 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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{CAUTION:
Do not load your vehicle any heavier than the
Gross Vehicle Weight Rating (GVWR), or either
the maximum front or rear Gross Axle Weight
Rating (GAWR). If you do, parts on your
vehicle can break, and it can change the way
your vehicle handles. These could cause you
to lose control and crash. Also, overloading
can shorten the life of your vehicle.
Notice:Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.
Using heavier suspension components to get added
durability might not change your weight ratings. Ask your
dealer to help you load your vehicle the right way.
If you put things inside your vehicle—like suitcases,
tools, packages, or anything else—they go as fast as the
vehicle goes. If you have to stop or turn quickly, or if
there is a crash, they’ll keep going.
{CAUTION:
Things you put inside your vehicle can strike
and injure people in a sudden stop or turn, or
in a crash.
Put things in the cargo area of your
vehicle. Try to spread the weight evenly.
Never stack heavier things, like suitcases,
inside the vehicle so that some of them
are above the tops of the seats.
Do not leave an unsecured child restraint
in your vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
Do not leave a seat folded down unless
you need to.
There’s also important loading information for off-road
driving in this manual. See “Loading Your Vehicle
for Off-Road Driving“ underOff-Road Driving with Your
Four-Wheel-Drive Vehicle on page 4-20.
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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.
Four-Wheel-Drive Vehicles Equipped with
Transfer Case (NP1, NP2 and NP8)
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.
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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 2-37for 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.
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.
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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.
{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 2-37for 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.
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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 2-48.
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 adequeate 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.
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 2-48.
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 adequeate clamping device to ensure that the
front wheels are locked into the straight position.
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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.
5. Shift the transfer case to NEUTRAL. See
Four-Wheel Drive on page 2-37.
6. Release the parking brake only after the vehicle
being towed is rmly attached to the tow vehicle.
7. Turn the ignition to LOCK.
Trailer Recommendations
You must subtract your hitch loads from the CWR for
your vehicle. Weigh your vehicle with the trailer
attached, so that you won’t go over the GVWR or
GAWR. If you are using a weight-distributing hitch,
weigh the vehicle without the spring bars in place.
You’ll get the best performance if you spread out the
weight of your load the right way, and if you choose the
correct hitch and trailer brakes.
For more information, seeTowing a Trailer on
page 4-68.
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