traction control GMC YUKON 2003 User Guide

The traction you can get in a curve depends on the
condition of your tires and the road surface, the angle at
which the curve is banked, and your speed. While
you’re in a curve, speed is the one factor you can
control.
Suppose you’re steering through a sharp curve.
Then you suddenly accelerate. Both control
systems—steering and acceleration—have to do their
work where the tires meet the road. Adding the
sudden acceleration can demand too much of those
places. You can lose control. SeeTraction Assist
System (TAS) on page 4-10.
What should you do if this ever happens? Ease up on
the accelerator pedal, steer the vehicle the way you
want it to go, and slow down.
Speed limit signs near curves warn that you should
adjust your speed. Of course, the posted speeds
are based on good weather and road conditions. Under
less favorable conditions you’ll want to go slower.
If you need to reduce your speed as you approach a
curve, do it before you enter the curve, while your front
wheels are straight ahead.Try to adjust your speed so you can“drive”through the
curve. Maintain a reasonable, steady speed. Wait to
accelerate until you are 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 andnd
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. You
can avoid these problems by braking—if you can stop
in time. But sometimes you can’t; there isn’t room.
That’s the time for evasive action - steering around the
problem.
Your vehicle can perform very well in emergencies like
these. First apply your brakes.
SeeBraking on page 4-6. It is better to remove as much
speed as you can from a possible collision. Then
steer around the problem, to the left or right depending
on the space available.
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Check your mirrors, glance over your shoulder and
start your left lane change signal before moving out
of the right lane to pass. When you are far
enough ahead of the passed vehicle to see its front
in your inside mirror, activate your right lane
change signal and move back into the right lane.
(Remember that if your right outside mirror is
convex, the vehicle you just passed may seem to
be farther away from you than it really is.)
Try not to pass more than one vehicle at a time on
two-lane roads. Reconsider before passing the
next vehicle.
Don’t overtake a slowly moving vehicle too rapidly.
Even though the brake lamps are notashing, it
may be slowing down or starting to turn.
If you’re being passed, make it easy for the
following driver to get ahead of you. Perhaps you
can ease a little to the right.
Loss of Control
Let’s review what driving experts say about what
happens when the three control systems (brakes,
steering and acceleration) don’t have enough friction
where the tires meet the road to do what the driver has
asked.
In any emergency, don’t 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 your vehicle’s
three control systems. In the braking skid, your wheels
aren’t 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.
A cornering skid is best handled by easing your foot off
the accelerator pedal.
If you have the Traction Assist System, remember: It
helps avoid only the acceleration skid. If you do not have
this system, or if the system is off, then an acceleration
skid is also best handled by easing your foot off the
accelerator pedal.
If your 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,
your vehicle may straighten out. Always be ready
for a second skid if it occurs.
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Of course, traction is reduced when water, snow, ice,
gravel or other material is on the road. For safety, you’ll
want to 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 engine braking by shifting to a
lower gear). Any sudden changes could cause the tires
to slide. You may not realize the surface is slippery
until your 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 anti-lock brake system (ABS) helps
avoid only the braking skid.
Off-Road Driving with Your
Four-Wheel-Drive Vehicle
This off-road guide is for vehicles that have four-wheel
drive. Also, seeBraking on page 4-6. If your vehicle
doesn’t have four-wheel drive, you shouldn’t drive
off-road unless you’re on a level, solid surface.Off-road driving can be great fun. But it does have
some denite hazards. The greatest of these is
the terrain itself.
“Off-roading”means you’ve left the great North American
road system behind. Traffic lanes aren’t marked.
Curves aren’t banked. There are no road signs.
Surfaces can be slippery, rough, uphill or downhill. In
short, you’ve gone right back to nature.
Off-road driving involves some new skills. And that’s
why it’s very important that you read this guide.
You’llnd many driving tips and suggestions. These will
help make your off-road driving safer and more
enjoyable.
If you think you will need some more ground clearance
at the front of your vehicle, you can easily remove
the front bumper lower air dam.
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Controlling your vehicle is the key to successful off-road
driving. One of the best ways to control your vehicle
is to control your speed. Here are some things to keep
in mind. At higher speeds:
you approach things faster and you have less time
to scan the terrain for obstacles.
you have less time to react.
you have more vehicle bounce when you drive over
obstacles.
you’ll need more distance for braking, especially
since you’re on an unpaved surface.
{CAUTION:
When you’re 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’re
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. You need to be familiar with the terrain
and its many different features. Here are some things to
consider.
Surface Conditions:Off-roading can take you over
hard-packed dirt, gravel, rocks, grass, sand, mud, snow
or ice. Each of these surfaces affects the steering,
acceleration and braking of your vehicle in different
ways. Depending upon the kind of surface you are on,
you may experience slipping, sliding, wheel spinning,
delayed acceleration, poor traction and longer braking
distances.
Surface Obstacles:Unseen or hidden obstacles can
be hazardous. A rock, log, hole, rut or bump can startle
you if you’re not prepared for them. Often these
obstacles are hidden by grass, bushes, snow or even
the rise and fall of the terrain itself. Here are 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?
(There’s more discussion of these subjects later.)
Will you have to stop suddenly or change direction
quickly?
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{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.
Driving in Mud, Sand, Snow or Ice
When you drive in mud, snow or sand, your wheels
won’t get good traction. You can’t accelerate as quickly,
turning is more difficult, and you’ll need longer braking
distances.
It’s best to use a low gear when you’re in mud—the
deeper the mud, the lower the gear. In really deep mud,
the idea is to keep your vehicle moving so you don’t
get stuck.
When you drive on sand, you’ll sense a change in
wheel traction. But it will depend upon how loosely
packed the sand is. On loosely packed sand (as
on beaches or sand dunes) your tires will tend to sink
into the sand. This has an effect on 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’s very easy to lose control. On
wet ice, for example, the traction is so poor that you will
have difficulty accelerating. And if you do get moving,
poor steering and difficult braking can cause you 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.
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Buying New Tires
Tofind out what kind and size of tires you need, look at
the Certification/Tire label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specifications (TPC
Spec) number on each tire’s sidewall. When you get
new tires, get ones with that same TPC Spec number.
That way your vehicle will continue to have tires
that are designed to give proper endurance, handling,
speed rating, traction, ride and other things during
normal service on your vehicle. If your tires have an
all-season tread design, the TPC number will be
followed by an“MS”(for mud and snow).
If you ever replace your tires with those not having a
TPC Spec number, make sure they are the same size,
load range, speed rating and construction type (bias,
bias-belted or radial) as your original tires.{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
or types (radial and bias-belted tires), the
vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes may also cause damage to your vehicle.
Be sure to use the same size and type tires on
all wheels. If your vehicle has 17 inch road
tires (those originally installed on your vehicle)
it is all right to drive with the 16 inch spare tire
that came with your vehicle. When new, your
vehicle included a spare tire and wheel
assembly with the same overall diameter as
your vehicle’s road tires and wheels. Because
this spare tire was developed for use on your
vehicle, it will not affect vehicle handling or
cause damage to your vehicle.
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{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rimanges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance. (This
applies only to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires. The Uniform Tire Quality Grading
system does not apply to deep tread, winter-type
snow tires, space-saver or temporary use spare tires,
tires with nominal rim diameters of 10 to 12 inches
(25 to 30 cm), or to some limited-production tires.While the tires available on General Motors passenger
cars and light trucks may vary with respect to these
grades, they must also conform to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
The treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions on a specified government test course.
For example, a tire graded 150 would wear one and
a half (1.5) times as well on the government course as
a tire graded 100. The relative performance of tires
depends upon the actual conditions of their use,
however, and may depart significantly from the norm
due to variations in driving habits, service practices and
differences in road characteristics and climate.
Traction–AA, A, B, C
The traction grades, from highest to lowest, are AA, A,
B, and C. Those grades represent the tire’s ability
to stop on wet pavement as measured under controlled
conditions on specified government test surfaces of
asphalt and concrete. A tire marked C may have poor
traction performance. Warning: The traction grade
assigned to this tire is based on straight-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.
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Tire Chains
{CAUTION:
If your vehicle has P265/75R16, LT265/75R16,
P265/70R16 or P265/70R17 size tires, don’t use
tire chains. They can damage your vehicle
because there’s not enough clearance. Tire
chains used on a vehicle without the proper
amount of clearance can cause damage to the
brakes, suspension or other vehicle parts. The
area damaged by the tire chains could cause
you to lose control of your vehicle and you or
others may be injured in a crash.
Use another type of traction device only if its
manufacturer recommends it for use on your
vehicle and tire size combination and road
conditions. Follow that manufacturer’s
instructions. To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device if it’s contacting your vehicle, and don’t
spin your wheels.
If you dond traction devices that willt,
install them on the rear tires.Notice:If you have a tire size other than P265/75R16,
LT265/75R16, P265/70R16 or P265/70R17 use tire
chains only where legal and only when you must. Use
chains that are the proper size for your tires. Install
them on the rear tires only.
Don’t use chains on the front tires.
Tighten them as tightly as possible with the ends
securely fastened. Drive slowly and follow the chain
manufacturer’s instructions. If you can hear the
chains contacting your vehicle, stop and retighten
them. If the contact continues, slow down until
it stops. Driving too fast or spinning the wheels with
chains on will damage your vehicle.
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Instrument Panel
Cluster.......................................................3-38
Overview..................................................... 3-4
Instrument Panel Brightness.............................3-18
Instrument Panel Fuse Block............................5-98
Interior Lamps................................................3-18
J
Jump Starting.................................................5-44
K
Key Lock Cylinders Service..............................6-12
Keyless Entry System....................................... 2-4
Keys............................................................... 2-3
L
Lamps
Exterior......................................................3-14
Interior.......................................................3-18
Lamps On Reminder.......................................3-16
Lap Belt........................................................1-37
Lap-Shoulder Belt...........................................1-28
LATCH System
Child Restraints...........................................1-58
Securing a Child Restraint Designed for the
LATCH System........................................1-61Leaving Your Vehicle With the Engine Running . . . 2-36
LEFT REAR DOOR AJAR................................3-69
Level Control..................................................4-59
Liftgate..........................................................2-12
Liftgate Glass and Liftgate................................2-13
Light
Air Bag Readiness.......................................3-40
Anti-Lock Brake System Warning...................3-44
Battery Warning..........................................3-42
Brake System Warning.................................3-43
Cruise Control.............................................3-52
Low Fuel Warning.......................................3-53
Malfunction Indicator....................................3-48
Passenger Air Bag Status Indicator................3-40
Safety Belt Reminder...................................3-39
Tow/Haul Mode...........................................3-52
Traction Off................................................3-45
Lighted Visor Vanity Mirror...............................2-16
Listening to a DVD................................3-97, 3-110
Loading Your Vehicle.......................................4-58
Loading Your Vehicle for Off-Road Driving..........4-25
Locking Rear Axle...........................................4-12
Lockout Protection..........................................2-12
Lock-Out Switch
.............................................2-15
Locks
Delayed Locking
........................................... 2-9
Door
........................................................... 2-7
Lockout Protection
.......................................2-12
Power Door
.................................................. 2-8
Programmable Automatic Door Locks
............... 2-9
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Theft-Deterrent Systems (cont.)
Content Theft-Deterrent................................2-16
Passlock
®...................................................2-18
Third Row......................................................1-64
Throttle, Adjustable..........................................2-21
Tilt Wheel........................................................ 3-7
Tilting the 50/50 Split Bench Seat.....................1-12
Tilting the Bench Seat.....................................1-16
Tire Inflation Check.........................................6-11
Tires.............................................................5-60
Buying New Tires........................................5-64
Chains.......................................................5-68
Changing a Flat Tire....................................5-69
If a Tire Goes Flat.......................................5-69
Inflation -- Tire Pressure...............................5-61
Inspection and Rotation................................5-61
Spare Tire..................................................5-88
Uniform Tire Quality Grading.........................5-65
Wheel Alignment and Tire Balance.................5-66
Wheel Replacement.....................................5-66
When It Is Time for New Tires......................5-63
To Use the Engine Coolant Heater....................2-22
Top Strap......................................................1-54
Top Strap Anchor Location...............................1-55
Torque Lock...................................................2-37
Total Weight on Your Vehicle’s Tires..................4-66
Tow/Haul Mode ...............................................2-25Tow/Haul Mode Light.......................................3-52
Towing
Recreational Vehicle.....................................4-55
Towing a Trailer..........................................4-61
Your Vehicle...............................................4-54
Traction
Assist System (TAS)....................................4-10
Off Light.....................................................3-45
Stabilitrak
®System......................................4-12
TRACTION ACTIVE........................................3-68
Traction Control Operation................................4-13
Trailer
Recommendations
.......................................4-60
Trailer Brakes
.................................................4-68
Trailer Wiring Harness
.....................................4-72
Transfer Case
........................................5-49, 5-51
Transfer Case and Front Axle (Four-Wheel Drive)
Inspection
...................................................6-16
Transmission
Fluid, Automatic
...........................................5-23
Temperature Gage
.......................................3-46
TRANSMISSION HOT
.....................................3-68
Transmission Operation, Automatic
....................2-22
Transmission, Transaxle, Transfer Case Unit
Repair Manual
............................................7-10
Transportation Options
...................................... 7-8
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