2009 GMC ENVOY tire type

5B(CD):Press to play a CD while listening to the
radio. The CD symbol displays when a CD is loaded.
RPT (Repeat):With the repeat setting, one track or an
entire CD can be repeated.
To use repeat, do the following:
To repeat a track, press and release the RPT button.
RPT displays. Press again to turn off repeat play.
To repeat the CD, press and hold the RPT button for
two seconds. RPT displays. Press again to turn off
repeat play.
6 RDM (Random) (Base Radio or MP3 Radio):Press
to hear the tracks in random, rather than sequential,
order. RDM ON displays. RDM T or RDM and the track
number displays when each track starts to play.
Press again to turn off random play. RDM OFF displays.
RDM (Random):With the random setting, tracks can
be listened to in random, rather than sequential,
order, on one CD or on all of the CDs. To use random,
do one of the following:
To play the tracks on the CD in random order,
press and release the RDM button. RANDOM ONE
displays. Press again to turn off random play.
To play the tracks on all of the CDs that are loaded
in random order, press and hold RDM for more
than two seconds. A beep sounds and RANDOM
ALL displays. Press again to turn off random play.
AUTO EQ (Automatic Equalization):Press to select
the equalization setting while playing a CD. The
equalization is stored when a CD is played. For more
information on AUTO EQ, see “AUTO EQ” listed
previously in this section.
©¨/opSEEK:Press the left arrow to go to the
start of the current or to the previous track.
On some radios, pressing the left arrow, if more than
10 seconds have played, goes to the start of the
current track.
Press the right arrow to go to the start of the next track.
If either arrow is pressed more than once, the player
continues moving backward or forward through the CD.
On some radios, pressing either arrow for more than
two seconds scans the previous or next tracks at ve to
eight seconds per track. SCAN and the track number
displays.
©SCAN¨:To scan one CD, press and hold either
SCAN, or depending on the radio, the TYPE arrow
for more than two seconds until SCAN or TRACK SCAN
displays and a beep is heard. The radio goes to the
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S-LIST FULL displays if more than 20 selections
are saved.
To play the song list, press the SONG LIST button.
One beep sounds and S-LIST displays. The recorded
tracks begin to play in the order they were saved.
Seek through the song list by using either SEEK or
TYPE arrow. Seeking past the last saved track returns
to the rst saved track.
To delete tracks from the song list:
1. Turn the CD player on.
2. Press the SONG LIST button to turn song list on.
S-LIST displays.
3. Press either SEEK or TYPE arrow to select the
desired track to be deleted.
4. Press and hold the SONG LIST button for
two seconds. When SONG LIST is pressed,
one beep sounds. After two seconds of continuously
pressing the SONG LIST button, two beeps sound
to conrm that the track has been deleted.
After a track has been deleted, the remaining tracks are
moved up the list. When another track is added to
the song list, the track is added to the end of the list.To delete the entire song list:
1. Turn the CD player on.
2. Press the SONG LIST button to turn song list on.
S-LIST displays.
3. Press and hold the SONG LIST button for more
than four seconds. One beep sounds, followed by
two beeps after two seconds, and a nal beep
sounds after four seconds. S-LIST EMPTY displays
indicating the song list has been deleted.
If a CD is ejected, and the song list contains saved
tracks from that CD, those tracks are automatically
deleted from the song list. Any tracks saved to the song
list again are added to the bottom of the list.
To end song list mode, press the SONG LIST button.
One beep sounds and S-LIST is removed from the
display.
Playing an MP3/WMA CD-R Disc
The vehicle’s radio system may have the MP3/WMA
feature. If it has this feature, it is capable of playing an
MP3/WMA CD-R disc. For more information on how
to play an MP3/WMA CD-R disc, seeUsing an MP3
on page 3-80later in this section.
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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 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 slipperyuntil 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.
Off-Road Driving
Vehicles with four-wheel drive can be used for off-road
driving. Vehicles without four-wheel drive should not be
driven off-road except on a level, solid surface.
The airbag system is designed to work properly under
a wide range of conditions, including off-road usage.
Always wear your safety belt and observe safe driving
speeds, especially on rough terrain.
Drinking and driving can be very dangerous on any road
and this is certainly true for off-road driving. At the very
time you need special alertness and driving skills, your
reexes, perceptions, and judgment can be affected
by even a small amount of alcohol. You could have a
serious — or even fatal — accident if you drink and drive
or ride with a driver who has been drinking.
Off-roading can be great fun but has some denite
hazards. The greatest of these is the terrain itself. When
off-road driving, traffic lanes are not marked, curves are
not banked, and there are no road signs. Surfaces can be
slippery, rough, uphill, or downhill.
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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 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.
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Low-Prole Performance Tire
If your vehicle has P255/50R20 size tires, they
are classied as low-prole performance tires.
These tires are designed for very responsive
driving on wet or dry pavement. You may
also notice more road noise with low-prole
performance tires and that they tend to wear
faster.
Notice:If the vehicle has low-prole tires,
they are more susceptible to damage from road
hazards or curb impact than standard prole
tires. Tire and/or wheel assembly damage
can occur when coming into contact with
road hazards like, potholes, or sharp edged
objects, or when sliding into a curb. The
vehicle warranty does not cover this type of
damage. Keep tires set to the correct ination
pressure and, when possible avoid contact
with curbs, potholes, and other road hazards.
Tire Sidewall Labeling
Useful information about a tire is molded into the
sidewall. The following illustration is an example
of a typical P-Metric tire sidewall.
(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.
Passenger (P-Metric) Tire
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(B) TPC Spec (Tire Performance Criteria
Specication):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) 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
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 5-72.
(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 5-60
andLoading the Vehicle on page 4-31.
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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.(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 passenger (P-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.
Speed ratings range from A to Z.
Passenger (P-Metric) Tire
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For additional information regarding how much
weight your vehicle can carry, and an example
of the Tire and Loading Information label,
seeLoading the Vehicle on page 4-31. How you
load your vehicle affects vehicle handling and
ride comfort. Never load your vehicle with more
weight than it was designed to carry.
When to Check
Check your tires once a month or more.
Do not forget to check the pressure of the spare
tire, if the vehicle has one. SeeSpare Tire on
page 5-102for additional information.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You cannot tell if your tires are properly
inated simply by looking at them. Radial tires
may look properly inated even when they areunderinated. 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).
Remove the valve cap from the tire valve stem.
Press the tire gage rmly onto the valve to
get a pressure measurement. If the cold tire
ination 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 overll 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.
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