tire type GMC ENVOY XL 2004 Owners Manual

To turn alternate frequency off, press and hold BAND
again for two seconds. AF OFF will appear on the
display. The radio will not switch to other stations.
This function does not apply for XM™ Satellite Radio
Service.
Setting Preset PTYs (RDS Only)
Up to 12 PTYs (six FM1 and six FM2), can be
programmed on the six numbered pushbuttons, by
performing the following steps:
1. Press BAND to select FM1 or FM2.
2. Turn the P-TYPE knob to activate program type
select mode. TYPE and a PTY will appear on the
display.
3. Turn the P-TYPE knob to select a PTY.
4. Press and hold one of the six numbered
pushbuttons until you hear a beep. Whenever that
numbered pushbutton is pressed, the PTY that
was set will return.
5. Repeat the steps for each pushbutton.
RDS Messages
ALERT!:Alert warns of local or national emergencies.
When an alert announcement comes on the current
radio station, ALERT! will appear on the display.You will hear the announcement, even if the volume is
low or a CD is playing. If a CD is playing, play will
stop during the announcement. Alert announcements
cannot be turned off.
ALERT! will not be affected by tests of the emergency
broadcast system. This feature is not supported by
all RDS stations.
INFO (Information):If the current station has a
message, the information symbol will appear on the
display. Press this button to see the message. The
message may display the artist, song title, call in phone
numbers, etc.
If the entire message is not displayed, parts of the
message will appear every three seconds. To scroll
through the message, press and release the INFO button.
A new group of words will appear on the display after
every press of the button. Once the complete message
has been displayed, the information symbol will
disappear from the display until another new message is
received. The last message can be displayed by pressing
the INFO button. You can view the last message until a
new message is received or a different station is tuned to.
When a message is not available from a station,
NO INFO will appear on the display.
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Setting Preset PTYs (RDS Only)
Up to 12 PTYs (six FM1 and six FM2), can be
programmed on the six numbered pushbuttons, by
performing the following steps:
1. Press BAND to select FM1 or FM2.
2. Turn the P-TYPE knob to activate program type
select mode. TYPE and a PTY will appear on the
display.
3. Turn the P-TYPE knob to select a PTY.
4. Press and hold one of the six numbered
pushbuttons until you hear a beep. Whenever that
numbered pushbutton is pressed, the PTY that
was set will return.
5. Repeat the steps for each pushbutton.
RDS Messages
ALERT!:Alert warns of local or national emergencies.
When an alert announcement comes on the current
radio station, ALERT! will appear on the display.
You will hear the announcement, even if the volume
is low or a cassette tape or CD is playing. If a
cassette tape or CD is playing, play will stop during
the announcement. Alert announcements cannot
be turned off.ALERT! will not be affected by tests of the emergency
broadcast system. This feature is not supported by
all RDS stations.
INFO (Information):If the current station has a
message, the information symbol will appear on the
display. Press this button to see the message. The
message may display the artist, song title, call in phone
numbers, etc.
If the entire message is not displayed, parts of the
message will appear every three seconds. To scroll
through the message, press and release the INFO
button. A new group of words will appear on the display
after every press of the button. Once the complete
message has been displayed, the information symbol
will disappear from the display until another new
message is received. The last message can be
displayed by pressing the INFO button. You can view
the last message until a new message is received
or a different station is tuned to.
When a message is not available from a station,
NO INFO will appear on the display.
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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
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.
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.Of course, traction is reduced when water, snow, ice,
gravel or other material is on the road. For safety,
you will 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.
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(A) Tire Size Code:The tire size code is a combination
of letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction type and
service description. See the “Tire Size Code” illustration
later in this section for more detail.
(B) Tire Performance Criteria Specication
(TPC Spec):Original equipment tires designed to
GM’s specic tire performance criteria have a TPC
specication code molded onto the sidewall. GM’s
TPC specications meet or exceed all federal safety
guidelines.
(C) Department of Transportation (DOT):
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
Identication 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 5-68.
(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 seeInation - Tire
Pressure on page 5-64andLoading Your Vehicle
on page 4-49.
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(A) Tire Size:The tire size code is a combination
of letters and numbers used to dene 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) Tire Performance Criteria Specication
(TPC Spec):Original equipment tires designed to
GM’s specic tire performance criteria have a TPC
specication code molded onto the sidewall. GM’s
TPC specications meet or exceed all federal safety
guidelines.
(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 conguration.
For information on recommended tire pressure see
Ination - Tire Pressure on page 5-64andLoading
Your Vehicle on page 4-49.
(D) Department of Transportation (DOT):
The Department of Transportation (DOT) code indicates
that the tire is in compliance with the U.S. Department
of Transportation Motor Vehicle Safety Standards.
LT-Metric Tire
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(E) Tire Identication Number (TIN):The letters
and numbers following DOT code are the Tire
Identication 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
seeInation - Tire Pressure on page 5-64and
Loading Your Vehicle on page 4-49.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 rst 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.Passenger (P-Metric) Tire
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(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 illustration, it would mean that the tire’s sidewall
is 75% 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. Speed ratings
range from “A” to “Z”.(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letter “LT”
as the rst 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 illustration, it would mean that the tire’s sidewall
is 75% as high as it is wide.Light Truck (LT-Metric) Tire
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(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. Speed ratings
range from “A” to “Z”. The light truck tire size example
above shows dual or single tire congurations.
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.
Aspect Ratio:The relationship of a tire’s height to
its width.Belt:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be made
from steel or other reinforcing materials.
Bead:The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
Bias Ply Tire:A pneumatic tire in which the plies are
laid at alternate angles less than 90 degrees to the
centerline of the tread.
Cold Ination Pressure:The amount of air pressure
in a tire, measured in pounds per square inch (psi)
or kilopascals (kPa) before a tire has built up heat from
driving. SeeInation - Tire Pressure on page 5-64.
Curb Weight:This means the weight of a motor vehicle
with standard and optional equipment including the
maximum capacity of fuel, oil and coolant, but without
passengers and cargo.
DOT Markings:A code molded into the sidewall
of a tire signifying that the tire is in compliance with
the U.S. Department of Transportation motor vehicle
safety standards. The DOT code includes the Tire
Identication Number (TIN), an alphanumeric designator
which can also identify the tire manufacturer, production
plant, brand and date of production.
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Ination - Tire Pressure
The tire and loading information label, shows the correct
ination pressures for your tires when they’re cold.
“Cold” means your vehicle has been sitting for at least
three hours or driven no more than 1 mile (1.6 km).
SeeLoading Your Vehicle on page 4-49, for the location
of your vehicle’s tire and loading information label.
Notice:Don’t let anyone tell you that underination
or overination is all right. It’s not. If your tires
don’t have enough air (underination), you can get
the following:
Too much exing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economyIf your tires have too much air (overination),
you can get the following:
Unusual wear
Bad handling
Rough ride
Needless damage from road hazards
When to Check
Check your tires once a month or more.
Also, check the tire pressure of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inated
simply by looking at them. Radial tires may look properly
inated even when they’re underinated. Check the tire’s
ination 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).
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Buying New Tires
To nd out what kind and size of tires you need, look
at the Certication/Tire label or the Tire and Loading
Information label. For examples of these labels and their
location on your vehicle, seeLoading Your Vehicle
on page 4-49.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specication (TPC Spec)
number on each tire’s sidewall. When you get new tires,
General Motors recommends that you get tires 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, load range, 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.
{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim anges 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.
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