2010 GMC TERRAIN traction control

Driving and Operating 8-7
tire contacts the pavement edge.
Then turn the steering wheel to go
straight down the roadway.
Loss of Control
Let us review what driving experts
say about what happens when the
three control systems—brakes,
steering, and acceleration —do not
have enough friction where the tires
meet the road to do what the driver
has asked.
In any emergency, do not give up.
Keep trying to steer and constantly
seek an escape route or area of
less danger.
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.
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 is 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 might
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 all‐wheel drive can be
used for off‐road driving. Vehicles
without all‐wheel drive should not be
driven off-road except on a level,
solid surface.

Driving and Operating 8-11
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.
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.

8-12 Driving and Operating
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(Continued)
WARNING (Continued)
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.

8-16 Driving and Operating
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.
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.

8-18 Driving and Operating
Driving on Wet Roads
Rain and wet roads can reduce
vehicle traction and affect your
ability to stop and accelerate.
Always drive slower in these types
of driving conditions and avoid
driving through large puddles and
deep‐standing or flowing water.
{WARNING
Wet brakes can cause crashes.
They might not work as well in a
quick stop and could cause
pulling to one side. You could
lose control of the vehicle.
After driving through a large
puddle of water or a car/vehicle
wash, lightly apply the brake
pedal until the brakes work
normally.(Continued)
WARNING (Continued)
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause your
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be
very cautious about trying to drive
through flowing water.
Hydroplaning
Hydroplaning is dangerous. Water
can build up under your vehicle's
tires so they actually ride on the
water. This can happen if the road is
wet enough and you are going fast
enough. When your vehicle is
hydroplaning, it has little or no
contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to
slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet
weather driving tips include:
.Allow extra following distance.
.Pass with caution.
.Keep windshield wiping
equipment in good shape.
.Keep the windshield washer fluid
reservoir filled.
.Have good tires with proper
tread depth. SeeTireson
page 9‑45.
.Turn off cruise control.
Highway Hypnosis
Always be alert and pay attention to
your surroundings while driving.
If you become tired or sleepy, find a
safe place to park your vehicle
and rest.
Other driving tips include:
.Keep the vehicle well ventilated.
.Keep interior temperature cool.

8-20 Driving and Operating
Winter Driving
Driving on Snow or Ice
Drive carefully when there is snow
or ice between the tires and the
road, creating less traction or grip.
Wet ice can occur at about 0°C
(32°F) when freezing rain begins to
fall, resulting in even less traction.
Avoid driving on wet ice or in
freezing rain until roads can be
treated with salt or sand.
Drive with caution, whatever the
condition. Accelerate gently so
traction is not lost. Accelerating too
quickly causes the wheels to spin
and makes the surface under the
tires slick, so there is even less
traction.
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.The
Antilock Brake System (ABS)
on page 8‑39improves vehicle
stability during hard stops on
slippery roads, but apply the brakes
sooner than when on dry pavement.
Allow greater following distance on
any slippery road and watch for
slippery spots. Icy patches can
occur on otherwise clear roads in
shaded areas. The surface of a
curve or an overpass can remain icy
when the surrounding roads are
clear. Avoid sudden steering
maneuvers and braking while
on ice.
Turn off cruise control, if equipped,
on slippery surfaces.Blizzard Conditions
Being stuck in snow can be in a
serious situation. Stay with the
vehicle unless there is help nearby.
If possible, use the Roadside
Assistance Program
on page 12‑6.
To get help and keep everyone in
the vehicle safe:
.Turn on the hazard warning
flashers.
.Tie a red cloth to an outside
mirror.
{WARNING
Snow can trap engine exhaust
under the vehicle. This may
cause exhaust gases to get
inside. Engine exhaust contains
carbon monoxide (CO) which
cannot be seen or smelled. It can
cause unconsciousness and even
death.
(Continued)

Driving and Operating 8-41
Hill Start Assist (HSA)
This vehicle has a Hill Start Assist
(HSA) feature, which may be useful
when the vehicle is stopped on a
grade. This feature is designed to
prevent the vehicle from rolling,
either forward or rearward, during
vehicle drive off. After driver
completely stops and holds the
vehicle in a complete standstill on a
grade, HSA will be automatically
activated. During the transition
period between when the driver
releases the brake pedal and starts
to accelerate to drive off on a grade,
HSA holds the braking pressure to
ensure that there is no rolling back.
The brakes will automatically
release when the accelerator pedal
is applied within the two second
window. It will not activate if the
vehicle is in a drive gear and facing
downhill or if the vehicle is facing
uphill and in R (Reverse).
Ride Control Systems
Traction Control
System (TCS)
The vehicle has a Traction Control
System (TCS) that limits wheel spin.
On a front-wheel-drive vehicle, the
system operates if it senses that
one or both of the front wheels are
spinning or beginning to lose
traction. On an All-Wheel-Drive
(AWD) vehicle, the system will
operate if it senses that any of the
wheels are spinning or beginning to
lose traction. When this happens,
the system brakes the spinning
wheel(s) and/or reduces engine
power to limit wheel spin.
The system may be heard or felt
while it is working, but this is
normal.The TCS/StabiliTrak warning light
will flash to indicate that the traction
control system is active.
This warning light comes on if there
is a problem with TCS, and the
system will not limit wheel spin.
Adjust your driving accordingly.
TCS automatically comes on
whenever the vehicle is started.
To limit wheel spin, especially in
slippery road conditions, the system
should always be left on. But, TCS
can be turned off if needed.
Notice:Do not repeatedly brake
or accelerate heavily when TCS is
off. The vehicle's driveline could
be damaged.

8-42 Driving and Operating
The TCS off light comes on and
“Traction Control Off”is displayed
on the Driver Information Center
(DIC) to indicate that the traction
control system has been turned off.
See Ride Control System Messages
on page 4‑33.
On AWD vehicles, when TCS is
turned off, the system may still
make noise. This is normal and
necessary with AWD hardware.
It may be necessary to turn the
system off if the vehicle ever gets
stuck in sand, mud or snow and
rocking the vehicle is required. See
If the Vehicle is Stuck
on page 8‑22for more information. See also
Winter Drivingon page 8‑20for
information on using TCS when
driving in snowy or icy conditions.
Traction control can be turned off by
pressing and releasing the TCS/
StabiliTrak button, on the console,
until the TCS/StabiliTrak light comes
on the instrument panel and
“Traction Control Off” appears in the
DIC. Press the button again to turn
the system back on. For information
on turning StabiliTrak off and on,
see “StabiliTrak System” following in
this section.
Adding non‐GM accessories can
affect the vehicle's performance.
See Accessories and Modifications
on page 9‑3for more information.
StabiliTrak System
The vehicle has a vehicle stability
enhancement system called
StabiliTrak. It is an advanced
computer controlled system that
assists with directional control of the
vehicle in difficult driving conditions.
StabiliTrak activates when the
computer senses a difference
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 help steer
the vehicle in the intended direction.