2004 GMC SIERRA DENALI wheel

Highway Hypnosis
Is there actually such a condition as ªhighway
hypnosisº? 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.
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Hill and Mountain RoadsDriving 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. See
Operating
Your All-Wheel-Drive Vehicle Off Paved Roads on
page 4-18
for information about driving off-road.
·Keep your vehicle in good shape. Check all ¯uid
levels and also the brakes, tires, cooling system
and transmission. These parts can work hard
on mountain roads.
·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.
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Driving on Snow or Ice
Most of the time, those places where your tires meet
the road probably have good traction.
However, if there is snow or ice between your tires and
the road, you can have a very slippery situation. You
will have a lot less traction or ªgripº and will need to be
very careful.
What is the worst time for this? ªWet ice.º Very cold
snow or ice can be slick and hard to drive on. But wet
ice can be even more trouble because it may offerthe least traction of all. You can get wet ice when it is
about freezing (32ÉF; 0ÉC) and freezing rain begins
to fall. Try to avoid driving on wet ice until salt and sand
crews can get there.
Whatever the condition Ð smooth ice, packed, blowing
or loose snow Ð drive with caution.
Accelerate gently. Try not to break the fragile traction. If
you accelerate too fast, the drive wheels will spin and
polish the surface under the tires even more.
Your anti-lock brakes improve your vehicle's stability
when you make a hard stop on a slippery road.
Even though you have an anti-lock braking system, you
will want to begin stopping sooner than you would on
dry pavement. See
Braking on page 4-6.
·Allow greater following distance on any
slippery road.
·Watch for slippery spots. The road might be ®ne
until you hit a spot that is covered with ice. On
an otherwise clear road, ice patches may appear in
shaded areas where the sun can not reach:
around clumps of trees, behind buildings or under
bridges. Sometimes the surface of a curve or
an overpass may remain icy when the surrounding
roads are clear. If you see a patch of ice ahead
of you, brake before you are on it. Try not to brake
while you are actually on the ice, and avoid
sudden steering maneuvers.
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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
ªrockingº 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 information about using tire chains on your
vehicle, see
Tire Chains on page 5-74.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. Then shift back
and forth between REVERSE (R) and a forward gear,
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, see
Towing
Your Vehicle on page 4-48.
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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. See
Roadside 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 ªRecreational Vehicle Towingº following.
Recreational Vehicle Towing
Recreational vehicle towing means towing your vehicle
behind another vehicle Ð such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as ªdinghy towingº (towing your
vehicle with all four wheels on the ground) and ªdolly
towingº (towing your vehicle with two wheels on
the ground and two wheels up on a device known
as a ªdollyº).
Your vehicle was not designed to be towed with any of
its wheels on the ground. If your vehicle must be
towed, see
Towing Your Vehicle on page 4-48.
Notice:Towing an all-wheel-drive vehicle with all
four wheels on the ground, or even with only two of
its wheels on the ground, will damage drivetrain
components. Do not tow an all-wheel-drive vehicle if
any of its wheels will be on the ground.
Loading Your Vehicle
It is very important to know how much weight your
vehicle can carry. This weight is called the vehicle
capacity weight and includes the weight of all occupants,
cargo and all nonfactory-installed options. Two labels
on your vehicle show how much weight it may properly
carry, the Tire and Loading Information label and the
Certi®cation/Tire label.
{CAUTION:
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
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.
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{CAUTION:
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
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.
This will help you decide how much cargo and installed
equipment your truck can carry.
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 ªLoading Your Vehicle
for Off-Road Drivingª under
Operating Your
All-Wheel-Drive Vehicle Off Paved Roads on page 4-18.
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Payload
Payload capacity is the maximum load capacity that
your vehicle can carry. Be sure to include the weight of
the occupants as part of your load. If you added any
accessories or equipment after your vehicle left
the factory, remember to subtract the weight of these
things from the payload. Your dealer can help you
with this.
Remember not to exceed the Gross Axle Weight
Rating (GAWR) of the front or rear axle.
Two-Tiered Loading
By positioning four 2º x 6º wooden planks across the
width of the pickup box, you can create an upper
load platform. The planks must be inserted in the pickup
box depressions. The length of the planks must allow
for at least a 3/4 inch (2 cm) bearing surface on
each end of the plank.
When using this upper load platform, be sure the load is
securely tied down to prevent it from shifting. The
load's center of gravity should be positioned in a zone
over the rear axle. The zone is located in the area
between the front of each wheel well and the rear of
each wheel well. The center of gravity height must not
extend above the top of the pickup box ¯areboard.Any load that extends beyond the vehicle's taillamp
area must be properly marked according to local laws
and regulations.
Remember not to exceed the Gross Axle Weight
Rating (GAWR) of the front or rear axle.
Add-On Equipment
When you carry removable items, you may need to put
a limit on how many people you carry inside your
vehicle. Be sure to weigh your vehicle before you buy
and install the new equipment.
Notice:Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.
Remember not to exceed the Gross Axle Weight
Rating (GAWR) of the front or rear axle.
*Equipment Maximum Weight
Ladder Rack and Cargo 750 lbs. (340 kg)
Cross Toolbox and Cargo 400 lbs. (181 kg)
Side Boxes and Cargo 250 lbs. per side
(113 kg per side)
*The combined weight for all rail-mounted equipment
should not exceed 1,000 lbs. (454 kg). A
reinforcement kit for rail-mounted add-on equipment is
recommended. See your dealer.
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Here is an example of proper truck and camper match:
A. Camper Center of Gravity
B. Recommended Center of Gravity Location Zone
The camper's center of gravity should fall within the
center of gravity zone for your vehicle's cargo load.
You must weigh any accessories or other equipment
that you add to your vehicle. Then, subtract this
extra weight from the CWR. This extra weight may
shorten the center of gravity zone of your vehicle. Your
dealer can help you with this.
If your slide-in camper and its load weighs less than the
CWR, the center of gravity zone for your vehicle may
be larger.Your dealer can help you make a good vehicle-camper
match. He'll also help you determine your CWR.
After you've loaded your vehicle and camper, drive to a
weigh station and weigh the front and rear wheels
separately. This will tell you the loads on your axles.
The loads on the front and rear axles shouldn't be more
than either of the GAWRs. The total of the axle loads
should not be more than the GVWR.
Open your driver's door and look at the Certi®cation/Tire
label to ®nd out your GAWR and GVWR.
If you've gone over your weight ratings, move or take
out some things until all the weight falls below the
ratings. Of course, you should always tie down any
loose items when you load your vehicle or camper.
When you install and load your slide-in camper, check
the manufacturer's instructions.
If you want more information on curb weights, cargo
weights, Cargo Weight Rating and the correct center of
gravity zone for your vehicle, your dealer can help
you. Just ask for a copy of²Consumer Information,
Truck-Camper Loading.²
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