Page 118 of 594

Black plate (50,1)GMC Sierra Owner Manual - 2011
3-50 Seats and Restraints
.Does the lap belt fit low and
snug on the hips, touching the
thighs? If yes, continue. If no,
return to the booster seat.
.Can proper safety belt fit be
maintained for the length of the
trip? If yes, continue. If no,
return to the booster seat.
Q: What is the proper way to wear safety belts?
A: An older child should wear a
lap-shoulder belt and get the
additional restraint a shoulder
belt can provide. The shoulder
belt should not cross the face
or neck. The lap belt should fit
snugly below the hips, just
touching the top of the thighs.
This applies belt force to the
child's pelvic bones in a crash.
It should never be worn over the
abdomen, which could cause
severe or even fatal internal
injuries in a crash. Also see
“Rear Safety Belt Comfort
Guides” underLap-Shoulder Belt on
page 3‑21.
According to accident statistics,
children and infants are safer
when properly restrained in a child
restraint system or infant restraint
system secured in a rear seating
position.
In a crash, children who are not
buckled up can strike other people
who are buckled up, or can be
thrown out of the vehicle. Older
children need to use safety belts
properly.
{WARNING
Never do this.
Never allow two children to wear
the same safety belt. The safety
belt can not properly spread the
impact forces. In a crash, the two
children can be crushed together
and seriously injured. A safety
belt must be used by only one
person at a time.
Page 289 of 594

Black plate (7,1)GMC Sierra Owner Manual - 2011
Climate Controls 8-7
Automatic Operation
AUTO (Automatic):When
automatic operation is active,
the system controls the inside
temperature, the air delivery,
and the fan speed.
Use the steps below to place the
entire system in automatic mode:
1. Press the AUTO button.
When AUTO is selected, the
display changes to show the
current temperature(s) and
AUTO is lit on the display.
The current air delivery mode
and fan speed are also
displayed for about five seconds.
When AUTO is selected, the air
conditioning operation and air
inlet are automatically controlled.
The air conditioning compressor
may run when the outside
temperature is above freezing. The air inlet will normally be set
to outside air. If it is hot outside,
the air inlet may automatically
switch to the recirculate mode to
help quickly cool down the air
inside the vehicle. The light
on the button comes on in
recirculation.
2. Set the driver and passenger temperature.
To find your comfort setting, start
with a 23°C (74°F) temperature
setting and allow about
20 minutes for the system to
regulate. Use the driver or
passenger temperature buttons
to adjust the temperature setting
as necessary. If a temperature
setting of 15°C (60°F) is chosen,
the system remains at the
maximum cooling setting.
If a temperature setting of
32°C (90°F) is chosen, the system remains at the maximum
heat setting. Choosing either
maximum setting will not cause
the vehicle to heat or cool any
faster.
Do not cover the solar sensor
located on the top of the instrument
panel near the windshield.
This sensor regulates air
temperature based on sun load.
For more information on the solar
sensor, see “Sensors”later in this
section.
To avoid blowing cold air in cold
weather, the system delays
turning the fan on until warm air
is available. The length of delay
depends on the engine coolant
temperature. Pressing the fan
switch overrides this delay and
changes the fan to a selected
speed.
Page 310 of 594

Black plate (16,1)GMC Sierra Owner Manual - 2011
9-16 Driving and Operating
Driving Across an Incline
An off-road trail will probably go
across the incline of a hill. To decide
whether to try to drive across the
incline, consider the following:
{WARNING
Driving across an incline that is
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, do not drive across it.
Find another route instead.
.A hill that can be driven straight
up or down might be too steep
to drive across. When going
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 driving
across an incline, the narrower
track width
—the distance
between the left and right
wheels —might not prevent the
vehicle from tilting and rolling
over. Driving across an incline
puts more weight on the downhill
wheels which could cause a
downhill slide or a rollover.
.Surface conditions can be a
problem. Loose gravel, muddy
spots, or even wet grass can
cause the 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, the vehicle can tilt
even more. For these reasons, carefully
consider whether to try to drive
across an incline. Just because
the trail goes across the incline
does not mean you have to drive it.
The last vehicle to try it might have
rolled over.
If you feel the vehicle starting
to slide sideways, turn downhill.
This should help straighten out
the vehicle and prevent the side
slipping. The best way to prevent
this is to
“walk the course” first, so
you know what the surface is like
before driving it.
Page 335 of 594

Black plate (41,1)GMC Sierra Owner Manual - 2011
Driving and Operating 9-41
WARNING (Continued)
You could be seriously injured.
Plug the cord into a properly
grounded three-prong 110-volt AC
outlet. If the cord will not reach,
use a heavy-duty three-prong
extension cord rated for at least
15 amps.
4. Before starting the engine, be sure to unplug and store the
cord as it was before to keep
it away from moving engine
parts. If you do not, it could
be damaged.
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.
Shifting Into Park
{WARNING
It can be dangerous to get out of
the vehicle if the shift lever is not
fully in P (Park) with the parking
brake firmly set. The vehicle can
roll. If you have left the engine
running, the vehicle can move
suddenly. You or others could
be injured. To be sure the vehicle
will not move, even when you are
on fairly level ground, use the
steps that follow. With four-wheel
drive, if the transfer case is in
N (Neutral), the vehicle will be
free to roll, even if the shift lever
is in P (Park). So, be sure the
transfer case is in a drive
gear —not in N (Neutral). If you
are pulling a trailer, see Driving
Characteristics and Towing Tips
on page 9‑91. 1. Hold the brake pedal down, then
set the parking brake.
See Parking Brake on page 9‑69
for more information.
2. Move the shift lever into the P (Park) position by pulling
the shift lever toward you and
moving it up as far as it will go.
3. Be sure the transfer case is in a drive gear —not in N (Neutral).
4. Turn the ignition key to LOCK/OFF.
5. Remove the key and take it with you. If you can leave the vehicle
with the ignition key in your
hand, the vehicle is in P (Park).