2010 GMC YUKON traction control

StabiliTrak®System
The vehicle has 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. See
Cruise Control on page 4‑7.
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
Driver Information Center (DIC), the vehicle should be
taken in for service. For more information on the DIC
messages, see Driver Information Center (DIC)
on
page 4‑47.
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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.
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 traction control and
StabiliTrak, press and hold the button for five seconds. Traction control and StabiliTrak can be turned on by
pressing and releasing the StabiliTrak button if not
automatically shut off for any other reason.
When the TCS or StabiliTrak system is turned off,
the StabiliTrak light and the appropriate TCS off or
StabiliTrak off 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 5‑29.
5-7

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.
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 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.
5-8

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.
Try to adjust the speed so you can drive through the
curve. Maintain a reasonable, steady speed. Wait to
accelerate until out of the curve, and then accelerate
gently into the straightaway.
Steering in Emergencies
There are times when steering can be more effective
than braking. For example, you come over a hill and
find a truck stopped in your lane, or a car suddenly
pulls out from nowhere, or a child darts out from
between parked cars and stops right in front of you.
These problems can be avoided by braking—if you
can stop in time. But sometimes you cannot stop in time
because there is no room. That is the time for evasive
action —steering around the problem.
The vehicle can perform very well in emergencies
like these. First, apply the brakes. See Braking
on
page 5‑3. It is better to remove as much speed as
possible from a collision. Then steer around the
problem, to the left or right depending on the space
available.
5-9

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.
Off-roading can be great fun but has some definite
hazards. The greatest of these is the terrain itself. When
off-road driving, traffic lanes are not marked, curves are
not banked, and there are no road signs. Surfaces can
be slippery, rough, uphill, or downhill.
Avoid sharp turns and abrupt maneuvers. Failure to
operate the vehicle correctly off‐road could result in loss
of vehicle control or vehicle rollover.
Off-roading involves some new skills. That is why it is
very important that you read these driving tips and
suggestions to help make off-road driving safer and
more enjoyable.
5-12

Controlling the vehicle is the key to successful off-road
driving. One of the best ways to control the vehicle is to
control the speed. At higher speeds:
.You approach things faster and have less time to
react.
.There is less time to scan the terrain for obstacles.
.The vehicle has more bounce when driving over
obstacles.
.More braking distance is needed, especially on an
unpaved surface.
{WARNING:
When you are driving off-road, bouncing and
quick changes in direction can easily throw you
out of position. This could cause you to lose
control and crash. So, whether you are driving on
or off the road, you and your passengers should
wear safety belts.
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.
5-16

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.
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.
5-17

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.
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