2010 GMC SIERRA traction 4

StabiliTrak®System
The vehicle may have a vehicle stability enhancement
system called StabiliTrak. It is an advanced computer
controlled system that assists the driver with directional
control of the vehicle in difficult driving conditions.
StabiliTrak activates when the computer senses a
discrepancy between the intended path and the
direction the vehicle is actually traveling. StabiliTrak
selectively applies braking pressure at any one of the
vehicle's brakes to assist the driver with keeping the
vehicle on the intended path.
When the vehicle is started and begins to move, the
system performs several diagnostic checks to insure
there are no problems. The system may be heard or felt
while it is working. This is normal and does not mean
there is a problem with the vehicle. The system should
initialize before the vehicle reaches 20 mph (32 km/h).
In some cases, it may take approximately two miles of
driving before the system initializes.
If cruise control is being used when StabiliTrak
activates, the cruise control automatically disengages.
The cruise control can be re-engaged when road
conditions allow. SeeCruise Control
on page 4‑7for
more information. If the system fails to turn on or activate, the StabiliTrak
light along with one of the following messages will be
displayed on the Driver Information Center (DIC):
TRACTION CONTROL OFF, SERVICE TRACTION
CONTROL, STABILITRAK OFF, SERVICE
STABILITRAK. If these DIC messages appear, make
sure the StabiliTrak system has not been turned off
using the StabiliTrak on/off button. Then turn the
steering wheel clockwise from the nine o'clock position
to the three o'clock position. If this clears the
message(s), the vehicle does not need servicing. If this
does not clear the message(s), then turn the vehicle off,
wait 15 seconds, and then turn it back on again to reset
the system. If any of these messages still appear on the
DIC, the vehicle should be taken in for service. For
more information on the DIC messages, see
DIC
Warnings and Messages on page 4‑65.
The StabiliTrak light will
flash on the instrument
panel cluster when the
system is both on and
activated.
The system may be heard or felt while it is working; this
is normal.
5-6

The traction control
disable button is located
on the instrument panel
below the climate
controls.
The traction control part of StabiliTrak can be turned
off by pressing and releasing the StabiliTrak button if
both systems (traction control and StabiliTrak) were
previously on. To disable both TCS and StabiliTrak,
press and hold the button for five seconds.
TCS and StabiliTrak can be turned on by pressing and
releasing the StabiliTrak button if not automatically shut
off for any other reason.
When TCS or StabiliTrak is turned off, the StabiliTrak
light and the appropriate message will be displayed on
the DIC to warn the driver. The vehicle will still have
brake-traction control when traction control is off, but
will not be able to use the engine speed management
system. See “Traction Control Operation” next for
more information.
When the traction control system has been turned off,
system noises may still be heard as a result of the
brake-traction control coming on. It is recommended to leave the system on for normal
driving conditions, but it may be necessary to turn the
system off if the vehicle is stuck in sand, mud, ice or
snow, and you want to
“rock”the vehicle to attempt to
free it. It may also be necessary to turn off the system
when driving in extreme off-road conditions where high
wheel spin is required. See If Your Vehicle is Stuck in
Sand, Mud, Ice, or Snow on page 5‑28.
When the transfer case is in 4LO, the stability system is
automatically disabled, the StabiliTrak light comes on
and the STABILITRAK OFF message will appear on the
DIC. Both traction control and StabiliTrak are
automatically disabled in this condition.
Traction Control Operation
The traction control system is part of the StabiliTrak
system. Traction control limits wheel spin by reducing
engine power to the wheels (engine speed
management) and by applying brakes to each individual
wheel (brake-traction control) as necessary.
The traction control system is enabled automatically
when the vehicle is started. It will activate and the
StabiliTrak light will flash if it senses that any of the
wheels are spinning or beginning to lose traction while
driving. If traction control is turned off, only the
brake-traction control portion of traction control will
work. The engine speed management will be disabled.
5-7

In this mode, engine power is not reduced automatically
and the driven wheels can spin more freely. This can
cause the brake-traction control to activate constantly.
Notice:If the wheel(s) of one axle is allowed to spin
excessively while the StabiliTrak, ABS and brake
warning lights and any relevant DIC messages are
displayed, the transfer case could be damaged.
The repairs would not be covered by the vehicle
warranty. Reduce engine power and do not spin the
wheel(s) excessively while these lights and
messages are displayed.
The traction control system may activate on dry or
rough roads or under conditions such as heavy
acceleration while turning or abrupt upshifts/downshifts
of the transmission. When this happens, a reduction in
acceleration may be noticed, or a noise or vibration may
be heard. This is normal.
If cruise control is being used when the system
activates, the StabiliTrak light will flash and cruise
control will automatically disengage. Cruise control may
be reengaged when road conditions allow. See Cruise
Control on page 4‑7.
StabiliTrak may also turn off automatically if it
determines that a problem exists with the system.
If the problem does not clear itself after restarting the
vehicle, see your dealer/retailer for service.Locking Rear Axle
Vehicles with a locking rear axle can give more traction
on snow, mud, ice, sand or gravel. It works like a
standard axle most of the time, but when traction is low,
this feature will allow the rear wheel with the most
traction to move the vehicle.
Steering
Power Steering
If the vehicle is a Two‐mode Hybrid, see the Two‐mode
Hybrid manual for more information.
If power steering assist is lost because the engine stops
or the system is not functioning, the vehicle can be
steered but it will take more effort.
Steering Tips
It is important to take curves at a reasonable speed.
Traction in a curve depends on the condition of the tires
and the road surface, the angle at which the curve is
banked, and vehicle speed. While in a curve, speed is
the one factor that can be controlled.
If there is a need to reduce speed, do it before entering
the curve, while the front wheels are straight.
5-8

Skidding
In a skid, a driver can lose control of the vehicle.
Defensive drivers avoid most skids by taking
reasonable care suited to existing conditions, and
by not overdriving those conditions. But skids are
always possible.
The three types of skids correspond to the vehicle's
three control systems. In the braking skid, the wheels
are not rolling. In the steering or cornering skid, too
much speed or steering in a curve causes tires to slip
and lose cornering force. And in the acceleration skid,
too much throttle causes the driving wheels to spin.
Remember: StabiliTrak
®helps avoid only the
acceleration skid. See StabiliTrak®Systemon
page 5‑6. If the StabiliTrak®System is off, then an
acceleration skid is best handled by easing your foot off
the accelerator pedal.
If the vehicle starts to slide, ease your foot off the
accelerator pedal and quickly steer the way you want
the vehicle to go. If you start steering quickly enough,
the vehicle may straighten out. Always be ready for a
second skid if it occurs.
Of course, traction is reduced when water, snow, ice,
gravel, or other material is on the road. For safety, slow
down and adjust your driving to these conditions. It is
important to slow down on slippery surfaces because
stopping distance will be longer and vehicle control
more limited. While driving on a surface with reduced traction, try
your best to avoid sudden steering, acceleration,
or braking, including reducing vehicle speed by shifting
to a lower gear. Any sudden changes could cause the
tires to slide. You may not realize the surface is slippery
until the vehicle is skidding. Learn to recognize warning
clues
—such as enough water, ice, or packed snow on
the road to make a mirrored surface —and slow down
when you have any doubt.
Remember: Antilock brakes help avoid only the
braking skid.
Off-Road Driving
Vehicles with four-wheel drive can be used for off-road
driving. Vehicles without four-wheel drive and vehicles
with 20‐inch tire/wheel assemblies should not be driven
off-road except on a level, solid surface.
The airbag system is designed to work properly under
a wide range of conditions, including off‐road usage.
Always wear your safety belt and observe safe driving
speeds, especially on rough terrain.
Drinking and driving can be very dangerous on any
road and this is certainly true for off-road driving. At the
very time you need special alertness and driving skills,
your reflexes, perceptions, and judgment can be
affected by even a small amount of alcohol. You could
have a serious —or even fatal —accident if you drink
and drive or ride with a driver who has been drinking.
5-11

Scanning the Terrain
Off-road driving can take you over many different kinds
of terrain. Be familiar with the terrain and its many
different features.
Surface Conditions :Off-roading surfaces can be
hard-packed dirt, gravel, rocks, grass, sand, mud, snow,
or ice. Each of these surfaces affects the vehicle's
steering, acceleration, and braking in different ways.
Depending on the surface, slipping, sliding, wheel
spinning, delayed acceleration, poor traction, and longer
braking distances can occur.
Surface Obstacles : Unseen or hidden obstacles can
be hazardous. A rock, log, hole, rut, or bump can startle
you if you are not prepared for them. Often these
obstacles are hidden by grass, bushes, snow, or even
the rise and fall of the terrain itself.
Some things to consider:
.Is the path ahead clear?
.Will the surface texture change abruptly up ahead?
.Does the travel take you uphill or downhill?
.Will you have to stop suddenly or change direction
quickly?
When driving over obstacles or rough terrain, keep a
firm grip on the steering wheel. Ruts, troughs, or other
surface features can jerk the wheel out of your hands. When driving over bumps, rocks, or other obstacles, the
wheels can leave the ground. If this happens, even with
one or two wheels, you cannot control the vehicle as
well or at all.
Because you will be on an unpaved surface, it is
especially important to avoid sudden acceleration,
sudden turns, or sudden braking.
Off-roading requires a different kind of alertness from
driving on paved roads and highways. There are no
road signs, posted speed limits, or signal lights. Use
good judgment about what is safe and what is not.
Driving on Hills
Off-road driving often takes you up, down, or across a
hill. Driving safely on hills requires good judgment and
an understanding of what the vehicle can and cannot
do. There are some hills that simply cannot be driven,
no matter how well built the vehicle.
{WARNING:
Many hills are simply too steep for any vehicle.
If you drive up them, you will stall. If you drive
down them, you cannot control your speed. If you
drive across them, you will roll over. You could be
seriously injured or killed. If you have any doubt
about the steepness, do not drive the hill.
5-15

Approaching a Hill
When you approach a hill, decide if it is too steep to
climb, descend, or cross. Steepness can be hard to
judge. On a very small hill, for example, there may be a
smooth, constant incline with only a small change in
elevation where you can easily see all the way to the
top. On a large hill, the incline may get steeper as you
near the top, but you might not see this because the
crest of the hill is hidden by bushes, grass, or shrubs.
Consider this as you approach a hill:
.Is there a constant incline, or does the hill get
sharply steeper in places?
.Is there good traction on the hillside, or will the
surface cause tire slipping?
.Is there a straight path up or down the hill so you
will not have to make turning maneuvers?
.Are there obstructions on the hill that can block
your path, such as boulders, trees, logs, or ruts?
.What is beyond the hill? Is there a cliff, an
embankment, a drop-off, a fence? Get out and
walk the hill if you do not know. It is the smart way
to find out.
.Is the hill simply too rough? Steep hills often have
ruts, gullies, troughs, and exposed rocks because
they are more susceptible to the effects of erosion.
Driving Uphill
Once you decide it is safe to drive up the hill:
.Use a low gear and get a firm grip on the
steering wheel.
.Get a smooth start up the hill and try to maintain
speed. Not using more power than needed can
avoid spinning the wheels or sliding.
{WARNING:
Turning or driving across steep hills can be
dangerous. You could lose traction, slide
sideways, and possibly roll over. You could be
seriously injured or killed. When driving up hills,
always try to go straight up.
.Try to drive straight up the hill if at all possible.
If the path twists and turns, you might want to find
another route.
.Ease up on the speed as you approach the top
of the hill.
.Attach a flag to the vehicle to be more visible to
approaching traffic on trails or hills.
5-16

Stalling on an Incline
{WARNING:
Getting out on the downhill (low) side of a vehicle
stopped across an incline is dangerous. If the
vehicle rolls over, you could be crushed or killed.
Always get out on the uphill (high) side of the
vehicle and stay well clear of the rollover path.
If the vehicle stalls when crossing an incline, be sure
you, and any passengers, get out on the uphill side,
even if the door there is harder to open. If you get out
on the downhill side and the vehicle starts to roll over,
you will be right in its path.
If you have to walk down the slope, stay out of the path
the vehicle will take if it does roll over.
Driving in Mud, Sand, Snow, or Ice
When you drive in mud, snow, or sand, the wheels do
not get good traction. Acceleration is not as quick,
turning is more difficult, and braking distances
are longer. It is best to use a low gear when in mud
—the deeper
the mud, the lower the gear. In really deep mud, keep
the vehicle moving so it does not get stuck.
When driving on sand, wheel traction changes. On
loosely packed sand, such as on beaches or sand
dunes, the tires will tend to sink into the sand. This
affects steering, accelerating, and braking. Drive at a
reduced speed and avoid sharp turns or abrupt
maneuvers.
Hard packed snow and ice offer the worst tire traction.
On these surfaces, it is very easy to lose control. On
wet ice, for example, the traction is so poor that you will
have difficulty accelerating. And, if the vehicle does get
moving, poor steering and difficult braking can cause it
to slide out of control.
{WARNING:
Driving on frozen lakes, ponds, or rivers can be
dangerous. Underwater springs, currents under
the ice, or sudden thaws can weaken the ice. Your
vehicle could fall through the ice and you and your
passengers could drown. Drive your vehicle on
safe surfaces only.
5-21

Driving in Water
{WARNING:
Driving through rushing water can be dangerous.
Deep water can sweep your vehicle downstream
and you and your passengers could drown. If it is
only shallow water, it can still wash away the
ground from under your tires, and you could lose
traction and roll the vehicle over. Do not drive
through rushing water.
Heavy rain can mean flash flooding, and flood waters
demand extreme caution.
Find out how deep the water is before driving through
it. Do not try it if it is deep enough to cover the wheel
hubs, axles, or exhaust pipe —you probably will not
get through. Deep water can damage the axle and
other vehicle parts. If the water is not too deep, drive slowly through it. At
faster speeds, water splashes on the ignition system
and the vehicle can stall. Stalling can also occur if you
get the tailpipe under water. If the tailpipe is under
water, you will never be able to start the engine. When
going through water, remember that when the brakes
get wet, it might take longer to stop. See
Driving in Rain
and on Wet Roads on page 5‑23.
After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis, or under the hood. These
accumulations can be a fire hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires, and exhaust system
for damage and check the fuel lines and cooling system
for any leakage.
The vehicle requires more frequent service due to
off-road use. Refer to the Maintenance Schedule for
additional information.
5-22