1998 GMC ENVOY flat tire

Poorly maintained and improperly used tires
are dangerous.
Overloading your tires can cause
overheating as
a result of too much friction.
You could have an air-out and
a serious
accident. See “Loading Your Vehicle” in
the Index.
Underinflated tires pose the same danger as
overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
Overinflated tires are more likely to be cut,
punctured or broken by a sudden impact
--
such as when you hit a pothole. Keep tires
at the recommended pressure.
Worn, old tires can cause accidents. If your
tread is badly worn, or if your tires have
been damaged, replace them.
Inflation -- Tire Pressure
The CertificatiodTire label, which is on the driver’s
door edge, above the door latch, shows the correct
inflation 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).
NOTICE:
Don’t let anyone tell you that underinflation or
overinflation is all right. It’s not.
If your tires
don’t have enough air (underinflation), you can
get the following:
Too much flexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy.
NOTICE: (Continued)
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NOTICE: (Continued)
If your tires have too much air (overinflation),
you can get the following:
0 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 inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
( 10 000 to 13 000 km). Any time you notice unusual
wear, rotate your tires
as soon as possible and check
wheel alignment.
Also check for damaged tires or
wheels. See “When It’s Time for New Tires” and
“Wheel Replacement” later in
this section for
more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The first
rotation is the most important. See “Scheduled
Maintenance Services”
in the Index for scheduled
rotation intervals.
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Q
+
I
!
When rotating your tires, always use one of the correct
rotation. patterns shown here.
After the tires
have been rotated, adjust the front and rear
inflation pressures as shown on the Certificationflire
label.
Make certain that all wheel nuts are properly tightened.
See “Wheel Nut Torque”
in the Index.
Rust or dirt on a wheel, or on the parts to which
it is fastened, can make wheel nuts become loose
after
a time. The wheel could come off and cause
an accident. When
you change a wheel, remove
any rust or dirt from places where the wheel
attaches
to the vehicle. In an emergency, you can
use a cloth or
a paper towel to do this; but be
sure to use a scraper or wire brush later,
if you
need to, to get all the rust or dirt off. (See
“Changing a Flat Tire”
in the Index.)
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Treadwear Temperature -- A, B, C
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 1/2) 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 -- A, B, C
The traction grades, from highest to lowest, are A, B,
and C, and they 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 braking (straight ahead) traction tests and does not
include cornering (turning) traction. The
temperature grades are
A (the highest), B, and C,
representing the tire’s resistance to the generation of
heat and its ability to dissipate heat when tested under
controlled conditions on
a specified indoor laboratory
test wheel. Sustained high temperature can cause the
material of the tire to degenerate and reduce tire life,
and excessive temperature can lead to sudden
tire
failure. The grade C corresponds to a level of
performance which all passenger car tires must meet
under the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels of
performance on the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
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NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper
height, vehicle ground clearance and tire
clearance to the body and chassis.
See “Changing a Flat Tire” in the Index for
more information.
Used Replacement Wheels
I
Putting a used wheel on your vehicle is
dangerous. You can’t know how it’s been used or
how far it’s been driven. It could fail suddenly
and cause an accident.
If you have to replace a
wheel, use a new GM original equipment wheel.
Tire Chains
NOTICE:
Don’t use tire chains. They can damage your
vehicle because there’s not enough clearance.
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 do find traction devices that will fit, install
them on the rear tires.
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I I M PORTANT:
KEEP ENGINE OIL
I
AT THE PROPER
LEVEL AND CHANGE AS
RECOMMENDED
Protection
Plan
Introduction
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle
in good working condition, but also helps the
environment. All recornmended maintenance procedures
are inymrtant. Improper vehicle maintenance can even
affect the quality
of the air we breathe. Improper fluid
levels or the wrong tire inflation can increase the level
of emissions fro111 your vehicle. To help protect OLI~
environment. and to keep your vehicle in good
condition, please maintain your vehicle properly.
How This Section is Organized
The remainder of this section is divided into five parts:
“Part A: Scheduled Maintenance Services” shows
what to have done and
how often. Some of these
services can be complex,
so unless you are technically
qualified and have
the necessary equipment, you should
let your dealer‘s service department
or another qualified
service center
do these jobs.
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Part B: Owner Checks an - Services Engine Coolant Level Check
Listed below are owner checks and services which
should be performed at the intervals specified to help
ensure the safety, dependability and emission control
performance of your vehicle.
Be sure any necessary repairs are completed at once.
Whenever any fluids or lubricants are added to your
vehicle, make sure they are the proper ones,
as shown in
Part D.
At Each Fuel Fill
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. See "Engine Oil" in the Index for
further details. Check
the engine coolant
level and add DEX-COOL'
coolant mixture
if necessary. See "Engine Coolant'' in
the Index for further details.
Windshield Washer Fluid Level Cl: -.
Check the windshield washer fluid level in the
windshield washer tank and add the proper fluid
if
necessary. See "Windshield Washer Fluid" in the Index
for further details.
At Least Once a Month
Tire Inflation Check
Make sure tires are inflated to the correct pressures. See
"Tires"
in the Index for further details.
Cassette Deck Service
Clean cassette deck. Cleaning should be done every
SO hours of tape play. See "Audio Systems" in the
Index for further details.
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Roadside Assistance
In
GMC’s Roadside Assistance provides stranded owners
with over-the-phone roadside repairs, location
of the
nearest GMC dealer or the following special services:
Flat Tire Chunge: Installation of spare tire will be
covered at
no charge (customer is responsible for repair
or replacement
of tire).
Fuel Delivery: Delivery
of enough fuel for the customer
to get
to the nearest service station (up to $4.00) will
be covered.
Jump Sturt: No-start situations which require a battery
jump start will be covered at no charge.
Luck Out: Replacement keys or locksmith service will
be covered at no charge if you are unable to gain entry
into your vehicle. Delivery
of the replacement key will
be covered at no charge within 10 miles (16 km).
Emergency Towing Service: Towing to the nearest
GMC dealer
for warranty related disablements will
be covered.
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