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.
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.
Driving and Operating 8-65
Total Weight on the
Vehicle's Tires
Inflate the vehicle's tires to the
upper limit for cold tires. These
numbers can be found on the
Certification label or seeVehicle
Load Limits
on page 8‑22for more
information. Do not go over the
GVW limit for the vehicle, or the
GAWR, including the weight of the
trailer tongue. If using a weight
distributing hitch, do not go over the
rear axle limit before applying the
weight distribution spring bars.
Towing Equipment
Hitches
Use the correct hitch equipment.
See your dealer/retailer or a hitch
dealer for assistance.
.The rear bumper on the vehicle
is not intended for hitches. Do
not attach rental hitches or other
bumper-type hitches to it. Use
only a frame-mounted hitch that
does not attach to the bumper.
.Will any holes be made in the
body of the vehicle when the
trailer hitch is installed? If there
are, seal the holes when the
hitch is removed. If the holes are
not sealed, dirt, water, and
deadly carbon monoxide (CO)
from the exhaust can get into the
vehicle. See Engine Exhaust
on
page 8‑34.
Safety Chains
Always attach chains between the
vehicle and the trailer. Cross the
safety chains under the tongue of
the trailer to help prevent the tongue
from contacting the road if it
becomes separated from the hitch.
Leave enough slack so the rig can
turn. Never allow safety chains to
drag on the ground.
Trailer Brakes
Does the trailer have its own
brakes? Be sure to read and follow
the instructions for the trailer brakes
so they are installed, adjusted and
maintained properly.
Because the vehicle has antilock
brakes, do not tap into the vehicle's
brake system. If this is done, both
brake systems will not work well,
or at all.
9-46 Vehicle Care
Tire Sidewall Labeling
Useful information about a tire is
molded into its sidewall. The
examples below show a typical
passenger vehicle tire and a
compact spare tire sidewall.
Passenger (P‐Metric) Tire Example
(A) Tire Size:The tire size is a
combination of letters and
numbers used to define a
particular tire's width, height,
aspect ratio, construction type, and service description. See the
“Tire Size”
illustration later in this
section for more detail.
(B) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet or
exceed all federal safety
guidelines.
(C) DOT (Department of
Transportation)
:The
Department of Transportation
(DOT) code indicates that the
tire is in compliance with the
U.S. Department of
Transportation Motor Vehicle
Safety Standards.
(D) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT (Department
of Transportation) code is the Tire Identification Number
(TIN). The TIN shows the
manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
(E) Tire Ply Material
:The type
of cord and number of plies in
the sidewall and under the tread.
(F) Uniform Tire Quality
Grading (UTQG)
:Tire
manufacturers are required to
grade tires based on three
performance factors: treadwear,
traction, and temperature
resistance. For more information
see Uniform Tire Quality
Grading
on page 9‑62.
(G) Maximum Cold Inflation
Load Limit
:Maximum load
that can be carried and the
maximum pressure needed to
support that load.
Vehicle Care 9-47
Compact Spare Tire Example
(A) Tire Ply Material:The type
of cord and number of plies in
the sidewall and under the tread.
(B) Temporary Use Only
:The
compact spare tire or temporary
use tire has a tread life of
approximately 5 000 km
(3,000 miles) and should not be
driven at speeds over 105 km/h
(65 mph). The compact spare
tire is for emergency use when a regular road tire has lost air and
gone flat. If your vehicle has
a compact spare tire, see
Compact Spare Tire
on
page 9‑76
and If a Tire Goes
Flat
on page 9‑67.
(C) Tire Identification Number
(TIN)
:The letters and numbers
following the DOT (Department
of Transportation) code is the
Tire Identification Number
(TIN). The TIN shows the
manufacturer and plant code,
tire size, and date the tire was
manufactured. The TIN is
molded onto both sides of the
tire, although only one side may
have the date of manufacture.
(D) Maximum Cold Inflation
Load Limit
:Maximum load
that can be carried and the
maximum pressure needed to
support that load. (E) Tire Inflation
:The
temporary use tire or compact
spare tire should be inflated to
420 kPa (60 psi). For more
information on tire pressure and
inflation see Tire Pressure
on
page 9‑52
.
(F) Tire Size
:A combination of
letters and numbers define a
tire's width, height, aspect ratio,
construction type, and service
description. The letter T as the
first character in the tire size
means the tire is for temporary
use only.
(G) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed to
GM's specific tire performance
criteria have a TPC specification
code molded onto the sidewall.
GM's TPC specifications meet or
exceed all federal safety
guidelines.
9-48 Vehicle Care
Tire Designations
Tire Size
The following illustration shows
an example of a typical
passenger vehicle tire size.
(A) Passenger (P‐Metric) Tire:
The United States version of a
metric tire sizing system. The
letter P as the first character in
the tire size means a passenger
vehicle tire engineered to
standards set by the U.S. Tire
and Rim Association.(B) Tire Width
:The three‐digit
number indicates the tire section
width in millimeters from
sidewall to sidewall.
(C) Aspect Ratio
:A two‐digit
number that indicates the tire
height‐to‐width measurements.
For example, if the tire size
aspect ratio is 60, as shown in
item C of the illustration, it would
mean that the tire's sidewall is
60 percent as high as it is wide.
(D) Construction Code
:A
letter code is used to indicate
the type of ply construction in
the tire. The letter R means
radial ply construction; the
letter D means diagonal or
bias ply construction; and the
letter B means belted‐bias ply
construction. (E) Rim Diameter
:Diameter of
the wheel in inches.
(F) Service Description
:These
characters represent the load
index and speed rating of the
tire. The load index represents
the load carry capacity a tire is
certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
Vehicle Care 9-53
How to Check
Use a good quality pocket-type
gauge to check tire pressure.
You cannot tell if your tires are
properly inflated simply by
looking at them. Radial tires may
look properly inflated even when
they are under‐inflated. Check
the tire's inflation pressure when
the tires are cold. Cold means
your vehicle has been sitting for
at least three hours or driven no
more than 1.6 km (1 mile).
Remove the valve cap from the
tire valve stem. Press the tire
gauge firmly onto the valve to
get a pressure measurement.If the cold tire inflation pressure
matches the recommended
pressure on the Tire and
Loading Information label, no
further adjustment is necessary.
If the inflation pressure is low,
add air until you reach the
recommended amount.
If you overfill the tire, release
air by pushing on the metal stem
in the center of the tire valve.
Re‐check the tire pressure with
the tire gauge.
Be sure to put the valve caps
back on the valve stems. They
help prevent leaks by keeping
out dirt and moisture.Tire Pressure Monitor
System
The Tire Pressure Monitor System
(TPMS) uses radio and sensor
technology to check tire pressure
levels. The TPMS sensors monitor
the air pressure in your vehicle's
tires and transmit tire pressure
readings to a receiver located in
the vehicle.
Each tire, including the spare
(if provided), should be checked
monthly when cold and inflated to
the inflation pressure recommended
by the vehicle manufacturer on the
vehicle placard or tire inflation
pressure label. (If your vehicle has
tires of a different size than the size
indicated on the vehicle placard or
tire inflation pressure label, you
should determine the proper tire
inflation pressure for those tires.)
Vehicle Care 9-61
SeeTire Inspectionon page 9‑58
andTire Rotationon page 9‑58
for information on proper tire
rotation.
{WARNING
Mixing tires could cause you
to lose control while driving.
If you mix tires of different
sizes, brands, or types (radial
and bias-belted tires), the
vehicle may not handle
properly, and you could have
a crash. Using tires of different
sizes, brands, or types may
also cause damage to your
vehicle. Be sure to use the
correct size, brand, and type
of tires on all wheels. It is all
right to drive with your
compact spare temporarily, as
it was developed for use on
your vehicle. See Compact
Spare Tire
on page 9‑76.
{WARNING
If you use bias-ply tires on the
vehicle, the wheel rim flanges
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 the vehicle.
If you must replace your
vehicle's tires with those that do
not have a TPC Spec number,
make sure they are the same
size, load range, speed rating,
and construction type (radial and
bias‐belted tires) as your
vehicle's original tires. Vehicles that have a tire
pressure monitoring system
could give an inaccurate
low‐pressure warning if non‐TPC
Spec rated tires are installed
on your vehicle. Non‐TPC
Spec rated tires may give a
low‐pressure warning that is
higher or lower than the proper
warning level you would get with
TPC Spec rated tires. See
Tire
Pressure Monitor System
on
page 9‑53
.
Your vehicle's original
equipment tires are listed on the
Tire and Loading Information
Label. See Vehicle Load Limits
on page 8‑22, for more
information about the Tire and
Loading Information Label and
its location on your vehicle.