
According to the American Medical Association, a 180 lb
(82 kg) person who drinks three 12 ounce (355 ml)
bottles of beer in an hour will end up with a BAC
of about 0.06 percent. The person would reach the
same BAC by drinking three 4 ounce (120 ml) glasses
of wine or three mixed drinks if each had 1-1/2 ounces
(45 ml) of liquors like whiskey, gin or vodka.
It's the amount of alcohol that counts. For example, if
the same person drank three double martinis (3 ounces
or 90 ml of liquor each) within an hour, the person'sBAC would be close to 0.12 percent. A person who
consumes food just before or during drinking will have a
somewhat lower BAC level.
There is a gender difference, too. Women generally
have a lower relative percentage of body water
than men. Since alcohol is carried in body water, this
means that a woman generally will reach a higher BAC
level than a man of her same body weight will when
each has the same number of drinks.
The law in an increasing number of U.S. states, and
throughout Canada, sets the legal limit at 0.08 percent.
In some other countries, the limit is even lower. For
example, it is 0.05 percent in both France and Germany.
The BAC limit for all commercial drivers in the United
States is 0.04 percent.
The BAC will be over 0.10 percent after three to six
drinks (in one hour). Of course, as we've seen, it
depends on how much alcohol is in the drinks, and how
quickly the person drinks them.
4-4

Control of a Vehicle
You have three systems that make your vehicle go where
you want it to go. They are the brakes, the steering and
the accelerator. All three systems have to do their work at
the places where the tires meet the road.
Sometimes, as when you're driving on snow or ice, it's
easy to ask more of those control systems than the
tires and road can provide. That means you can lose
control of your vehicle. Also see
Traction Assist System
(TAS) on page 4-10.
Braking
Braking action involvesperception timeandreaction
time.
First, you have to decide to push on the brake pedal.
That'sperception time.Then you have to bring up your
foot and do it. That'sreaction time.
Averagereaction timeis about 3/4 of a second. But
that's only an average. It might be less with one driver
and as long as two or three seconds or more with
another. Age, physical condition, alertness, coordination
and eyesight all play a part. So do alcohol, drugs and
frustration. But even in 3/4 of a second, a vehicle moving
at 60 mph (100 km/h) travels 66 feet (20 m). That
could be a lot of distance in an emergency, so keeping
enough space between your vehicle and others is
important.
And, of course, actual stopping distances vary greatly
with the surface of the road (whether it's pavement
or gravel); the condition of the road (wet, dry, icy); tire
tread; the condition of your brakes; the weight of
the vehicle and the amount of brake force applied.
4-6

Driving Across an Incline
Sooner or later, an off-road trail will probably go across
the incline of a hill. If this happens, you have to
decide whether to try to drive across the incline. Here
are some things to consider:
·A hill that can be driven straight up or down may be
too steep to drive across. When you go straight up
or down a hill, the length of the wheel base (the
distance from the front wheels to the rear wheels)
reduces the likelihood the vehicle will tumble
end over end. But when you drive across an incline,
the much more narrow track width (the distance
between the left and right wheels) may not prevent
the vehicle from tilting and rolling over. Also,
driving across an incline puts more weight on the
downhill wheels. This could cause a downhill
slide or a rollover.
·Surface conditions can be a problem when you
drive across a hill. Loose gravel, muddy spots,
or even wet grass can cause your tires to slip
sideways, downhill. If the vehicle slips sideways, it
can hit something that will trip it (a rock, a rut,
etc.) and roll over.
·Hidden obstacles can make the steepness of the
incline even worse. If you drive across a rock
with the uphill wheels, or if the downhill wheels drop
into a rut or depression, your vehicle can tilt even
more.For reasons like these, you need to decide carefully
whether to try to drive across an incline. Just because
the trail goes across the incline doesn't mean you
have to drive it. The last vehicle to try it might have
rolled over.
{CAUTION:
Driving across an incline that's too steep will
make your vehicle roll over. You could be
seriously injured or killed. If you have any
doubt about the steepness of the incline, don't
drive across it. Find another route instead.
Q:What if I'm driving across an incline that's not
too steep, but I hit some loose gravel and start
to slide downhill. What should I do?
A:If you feel your vehicle starting to slide sideways,
turn downhill. This should help straighten out the
vehicle and prevent the side slipping. However,
a much better way to prevent this is to get out and
ªwalk the courseº so you know what the surface
is like before you drive it.
4-28

{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. See ªParking Brakeº in the
Index.
4. Shift the transfer case to NEUTRAL (N). See
Four-Wheel Drive on page 2-34for the proper
procedure to select the neutral position for your
vehicle.
5. Release the parking brake only after the vehicle
being towed is ®rmly attached to the towing
vehicle.
6. When the vehicle is properly attached to the tow
vehicle and is ready to be towed, turn the ignition
to LOCK.
Loading Your Vehicle
The Certi®cation/Tire label is found on the rear edge of
the driver's door.
The label shows the size of your original tires and the
in¯ation pressures needed to obtain the gross weight
capacity of your vehicle. This is called the GVWR (Gross
Vehicle Weight Rating). The GVWR includes the
weight of the vehicle, all occupants, fuel and cargo.
4-51

The Certi®cation/Tire label also tells you the maximum
weights for the front and rear axles, called Gross
Axle Weight Rating (GAWR). To ®nd out the actual loads
on your front and rear axles, you need to go to a
weigh station and weigh your vehicle. Your dealer can
help you with this. Be sure to spread out your load
equally on both sides of the centerline.
Never exceed the GVWR for your vehicle, or the GAWR
for either the front or rear axle.
The Certi®cation/Tire label also contains information
about your Front Axle Reserve Capacity. See
Four-Wheel Drive on page 5-50.
And, if you do have a heavy load, you should spread it
out.
{CAUTION:
In the case of a sudden stop or collision,
things carried in the bed of your truck could
shift forward and come into the passenger
area, injuring you and others. If you put things
in the bed of your truck, you should make sure
they are properly secured.
{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.
Your warranty does not cover parts or components that
fail because of overloading.
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.
4-52

{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.
·Don't leave an unsecured child restraint in
your vehicle.
·When you carry something inside the
vehicle, secure it whenever you can.
·Don't 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 Drivingº under
Off-Road Driving with Your
Four-Wheel-Drive Vehicle on page 4-19.
Add-On Equipment
When you carry removable items, you may need to put
a limit on how many people you can carry inside
your vehicle. Be sure to weigh your vehicle before you
buy and install the new equipment.
Notice:Your warranty does not cover parts or
components that fail because of overloading.
Remember not to exceed the Gross Axle Weight Rating
(GAWR) of the front or rear axle. See
Loading Your
Vehicle on page 4-51.
The Cargo Weight Rating (CWR) is the maximum
weight of the load your vehicle can carry. It doesn't
include the weight of the people inside. But you
can ®gure about 150 lbs. (68 kg) for each seat.
The total cargo load must not be more than your
vehicle's CWR.
Level Control
Self-Adjusting
The self-adjusting rear suspension is available on
C/K 1500 vehicles and is available with the premium
smooth ride suspension package.
This type of level control will provide a leveled riding
position as well as improved handling under a variety of
passenger and loading conditions.
4-53

A hydraulic pump inside each rear shock absorber
raises the rear of the vehicle to the proper height, based
on inputs from the road surface, while the vehicle is
being driven. It take approximately 2 miles (3.2 km) of
driving for the leveling to complete, depending on
the road surface conditions.
If the loaded vehicle is not moved for approximately
12 hours, the leveling system may bleed down to a lower
height. This can be especially apparent if a trailer is
left attached to a parked vehicle for long periods of time.
The vehicle must be driven to re-level the vehicle.
If a self-equalizing hitch is being used, the vehicle
should be driven approximately 2 miles (3.2 km) with the
trailer prior to adjusting (leveling) the hitch.
Adding a Snow Plow or Similar
Equipment
Before installing a snow plow on your vehicle, here are
some things you'll need to know:
Notice:If your vehicle doesn't have the snow plow
prep package, adding a plow can damage your
vehicle, and the repairs wouldn't be covered
by warranty. Unless your vehicle was built to carry
a snow plow, don't add one to your vehicle. If
your vehicle has the snow plow option called RPO
VYU (snow plow prep package), then the payloadyour vehicle can carry will be reduced when a snow
plow is installed. Your vehicle can be damaged if
either the front or rear axle ratings, or the GVW, are
exceeded.
Q:How do I know if my vehicle can handle a snow
plow?
A:Some vehicles are built with a special package,
called RPO VYU (snow plow prep package). If
your vehicle has this option, you can add a plow to
it, provided certain weights, such as the weights
on the vehicle's axles and the GVW, aren't
exceeded.
Q:How heavy can a snow plow safely be?
A:The plow your vehicle can carry depends on many
things, such as:
·The options your vehicle came with, and the weight
of those options,
·The weight and number of passengers you intend
to carry,
·The weight of items you've added to your vehicle,
like a tool box or truck cap,
·The total weight of any additional cargo you intend
to carry.
4-54

Say, for example, you have a 700 lb. (318 kg) snow
plow. The total weight of all occupants and cargo inside
the cab should not exceed 300 lb. (135 kg). This
means that you may only be able to carry one
passenger. But, even this may be too much if you've
got other equipment already adding to the weight of your
vehicle.
Here are some guidelines for safely carrying a snow
plow on your vehicle:
·Make sure the weight on the front and rear axles
doesn't exceed the axle rating for each.
·For the front axle, if more cargo or passengers must
be carried, appropriate counter ballast must be
installed rear of the rear axle. Counter ballast must
be properly secured so it won't move during driving.
·Follow the snow plow manufacturer's
recommendations regarding rear ballast. Rear
ballast may be required to ensure a proper front and
rear weight distribution ratio, even though the actual
weight at the front axle may be less than the front
axle rating.
·The snow plow manufacturer or installer can assist
you in determining the amount of rear ballast
required, to help make sure your snowplow/vehicle
combination does not exceed the GVW rating, the
front and rear axle ratings, and the front and rear
weight distribution ratio.
·The total vehicle must not exceed the GVW rating.
Q:What is front axle reserve capacity, and how do
I calculate it?
A:Front axle reserve capacity is the difference
between your front GAWR and the front axle
weight of your truck with full fuel and passengers.
Basically, it's the amount of weight you can
add to your front axle before reaching your front
GAWR.
The front axle reserve capacity for your vehicle can be
found in the lower right corner of the Certi®cation/Tire
label, as shown.
United States
Canada
4-55