2009 GMC SAVANA tire type

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, 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 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.Of course, traction is reduced when water, snow, ice,
gravel, or other material is on the road. For safety, you
want to 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
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 Antilock Brake System (ABS) helps
avoid only the braking skid.
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Driving at Night
Night driving is more dangerous than day driving because
some drivers are likely to be impaired — by alcohol or
drugs, with night vision problems, or by fatigue.
Night driving tips include:
•Drive defensively.
•Do not drink and drive.
•Reduce headlamp glare by adjusting the inside
rearview mirror.
•Slow down and keep more space between you and
other vehicles because headlamps can only light up
so much road ahead.
•Watch for animals.
•When tired, pull off the road.
•Do not wear sunglasses.
•Avoid staring directly into approaching headlamps.
•Keep the windshield and all glass on your vehicle
clean — inside and out.
•Keep your eyes moving, especially during turns or
curves.
No one can see as well at night as in the daytime.
But, as we get older, these differences increase.
A 50-year-old driver might need at least twice as much
light to see the same thing at night as a 20-year-old.
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 flowing
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 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.
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Tire Sidewall Labeling
Useful information about a tire is molded into the
sidewall. The following illustrations are examples
of a typical P-Metric and a LT-Metric tire sidewall.
(A) Tire Size
:The tire size code 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
Specication)
: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 Identication Number (TIN)
:The letters
and numbers following DOT code are 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, seeUniform Tire Quality Grading
on page 5-74.
Passenger (P-Metric) Tire
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(G) Maximum Cold Ination Load Limit:Maximum load that can be carried and the
maximum pressure needed to support that load.
For information on recommended tire pressure
seeInflation - Tire Pressure on page 5-62and
Loading the Vehicle on page 4-18.(A) Tire Size:The tire size code 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
Specication)
: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. This does not apply to
Goodyear LT225/75R16 G949 RSA and Goodyear
LT225/75R16 G933 RSD commercial truck tires.
(C) Dual Tire Maximum Load
:Maximum load
that can be carried and the maximum pressure
needed to support that load when used in a dual
configuration. For information on recommended tire
pressure seeInflation - Tire Pressure on page 5-62
andLoading the Vehicle on page 4-18.
Light Truck (LT-Metric) Tire
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(D) 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.
(E) Tire Identication Number (TIN)
:The letters
and numbers following DOT code are 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.
(F) Tire Ply Material
:The type of cord and
number of plies in the sidewall and under
the tread.
(G) Single Tire Maximum Load
:Maximum load
that can be carried and the maximum pressure
needed to support that load when used as a single.
For information on recommended tire pressure see
Inflation - Tire Pressure on page 5-62andLoading
the Vehicle on page 4-18.
Tire Size
The following examples show the different parts of
a 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.
Passenger (P-Metric) Tire
Light Truck (LT-Metric) Tire
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(A) Light Truck (LT-Metric) Tire:The United
States version of a metric tire sizing system.
The letters LT as the first two characters in the
tire size means a light truck 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 75, as
shown in item C of the light truck (LT-Metric) tire
illustration, it would mean that the tire’s sidewall
is 75 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
:The service description
indicates the load range and speed rating of a tire.
The load index can range from 1 to 279. The speed
rating is the maximum speed a tire is certified to
carry a load. Speed ratings range from A to Z.
This does not apply to Goodyear LT225/75R16
G949 RSA and Goodyear LT225/75R16 G933 RSD
commercial truck tires; see the dual tire and
single tire maximum load and load range letter
designations on the tire sidewall.
Tire Terminology and Denitions
Air Pressure:The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
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How to Check
Use a good quality pocket-type gage 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
underinflated. 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 mile (1.6 km).
Remove the valve cap from the tire valve stem.
Press the tire gage 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 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.
Recheck the tire pressure with the tire gage.
Be sure to put the valve caps back on the valve
stems. They help prevent leaks by keeping out dirt
and moisture.
Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel
bolt or wheel nut is replaced, check the wheel nut torque
after 100, 1,000 and 6,000 miles (160, 1 600 and
10 000 km) of driving. For proper wheel nut tightening
information, see “Removing the Flat Tire and Installing
the Spare Tire” later in this section, underChanging a
Flat Tire on page 5-80. Also see “Wheel Nut Torque”
underCapacities and Specifications on page 5-110.
The outer tire on a dual wheel setup generally wears
faster than the inner tire. Your tires will wear more
evenly and last longer if you rotate the tires periodically.
SeeTire Inspection and Rotation on page 5-69.
Also seeScheduled Maintenance on page 6-4.
{CAUTION:
If you operate your vehicle with a tire that is badly
underinflated, the tire can overheat. An overheated
tire can lose air suddenly or catch fire. You or
others could be injured. Be sure all tires (including
the spare) are properly inflated.
SeeTires on page 5-54andInflation - Tire Pressure on
page 5-62for more information on proper tire inflation.
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Buying New Tires
GM has developed and matched specific 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 Specification
(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 specifications 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 a MS, for mud and snow.
SeeTire Sidewall Labeling on page 5-55for additional
information.
GM recommends replacing tires in sets of four (or six
if your vehicle has dual rear wheels). 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 5-69for
information on proper tire rotation.{CAUTION:
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 your vehicle’s wheels.
{CAUTION:
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.
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