traction control CHEVROLET SUBURBAN 2009 User Guide

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. SeeIf Your Vehicle is Stuck in
Sand, Mud, Ice, or Snow on page 4-31.
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 ash 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 ash and cruise
control will automatically disengage. Cruise control
may be reengaged when road conditions allow.
SeeCruise Control on page 3-12.
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.
4-8

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.
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.
4-9

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. SeeStabiliTrak®System on page 4-6.
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: Any Antilock Brake System (ABS) helps
avoid only the braking skid.
4-12

Getting Familiar with Off-Road Driving
It is a good idea to practice in an area that is safe
and close to home before you go into the wilderness.
Off-roading requires some new and different skills.
Tune your senses to different kinds of signals. Your eyes
need to constantly sweep the terrain for unexpected
obstacles. Your ears need to listen for unusual tire
or engine sounds. Use your arms, hands, feet, and
body to respond to vibrations and vehicle bounce.
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.
{CAUTION:
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.
4-16

Stalling on an Incline
{CAUTION:
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.
{CAUTION:
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.
4-23

Driving in Rain and 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 owing water.
{CAUTION:
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.
Flowing or rushing water creates strong forces.
Driving through owing 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 owing 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 uid reservoir lled.
Have good tires with proper tread depth.
SeeTires on page 5-61.
Turn off cruise control.
4-26

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 32°F (0°C) 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.TheStabiliTrak
®System on page 4-6improves the
ability to accelerate on slippery roads, but slow down and
adjust your driving to the road conditions. When driving
through deep snow, turn off the traction control part of the
StabiliTrak
®System to help maintain vehicle motion at
lower speeds.
TheAntilock Brake System (ABS) on page 4-5improves
vehicle stability during hard stops on a 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.
4-29

Rocking Your Vehicle to Get It Out
Turn the steering wheel left and right to clear the
area around the front wheels. For four-wheel-drive
vehicles, shift into Four-Wheel High or Four-Wheel Low.
For vehicles with StabiliTrak
®, turn the traction control
part of the system off. Shift back and forth between
R (Reverse) and a forward gear, spinning the wheels
as little as possible. To prevent transmission wear,
wait until the wheels stop spinning before shifting
gears. Release the accelerator pedal while shifting,
and press lightly on the accelerator pedal when
the transmission is in gear. Slowly spinning the
wheels in the forward and reverse directions causes
a rocking motion that could free the vehicle. If that
does not get the vehicle out after a few tries, it might
need to be towed out. Recovery hooks can be used,
if the vehicle has them. If the vehicle does need
to be towed out, seeTowing Your Vehicle on page 4-43.
Recovery Hooks
{CAUTION:
These hooks, when used, are under a lot of force.
Always pull the vehicle straight out. Never pull on
the hooks at a sideways angle. The hooks could
break off and you or others could be injured from
the chain or cable snapping back.
4-32

Service
For service and parts needs, visit your dealer/retailer.
You will receive genuine GM parts and GM-trained and
supported service people.
Genuine GM parts have one of these marks:
Accessories and Modications
When non-dealer/non-retailer accessories are added to
the vehicle, they can affect vehicle performance and
safety, including such things as airbags, braking, stability,
ride and handling, emissions systems, aerodynamics,
durability, and electronic systems like antilock brakes,
traction control, and stability control. Some of these
accessories could even cause malfunction or damage
not covered by the vehicle warranty.
Damage to vehicle components resulting from the
installation or use of non-GM certied parts, including
control module modications, are not covered under the
terms of the vehicle warranty and may affect remaining
warranty coverage for affected parts.
GM Accessories are designed to complement and
function with other systems on the vehicle. Your GM
dealer/retailer can accessorize the vehicle using genuine
GM Accessories. When you go to your GM dealer/
retailer and ask for GM Accessories, you will know that
GM-trained and supported service technicians will
perform the work using genuine GM Accessories.
Also, seeAdding Equipment to Your Airbag-Equipped
Vehicle on page 1-96.
5-3

You need new tires if any of the following statements
are true:
You can see the indicators at three or more places
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut, or snagged
deep enough to show cord or fabric.
The tire has a bump, bulge, or split.
The tire has a puncture, cut, or other damage that
cannot be repaired well because of the size or
location of the damage.
The rubber in tires degrades over time, even if they are
not being used. This is also true for the spare tire, if
your vehicle has one. Multiple conditions affect how fast
this aging takes place, including temperatures, loading
conditions, and ination pressure maintenance. With
proper care and maintenance tires will typically wear out
before they degrade due to age. If you are unsure
about the need to replace your tires as they get older,
consult the tire manufacturer for more information.
Buying New Tires
GM has developed and matched specic tires for your
vehicle. The original equipment tires installed on your
vehicle, when it was new, were designed to meet General
Motors Tire Performance Criteria Specication (TPC
spec) system rating. If you need replacement tires,
GM strongly recommends that you get tires with the
same TPC Spec rating. This way, your vehicle will
continue to have tires that are designed to give the
same performance and vehicle safety, during normal use,
as the original tires.
GM’s exclusive TPC Spec system considers over a
dozen critical specications that impact the overall
performance of your vehicle, including brake system
performance, ride and handling, traction control, and tire
pressure monitoring performance. GM’s TPC Spec
number is molded onto the tire’s sidewall near the tire
size. If the tires have an all-season tread design, the TPC
spec number will be followed by an MS for mud and
snow. SeeTire Sidewall Labeling on page 5-62for
additional information.
GM recommends replacing tires in sets of four. This is
because uniform tread depth on all tires will help keep
your vehicle performing most like it did when the tires
were new. Replacing less than a full set of tires can affect
the braking and handling performance of your vehicle.
SeeTire Inspection and Rotation on page 5-76for
information on proper tire rotation.
5-78