2003 GMC YUKON DENALI flat tire

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
0 Tire overloading
Bad wear
Bad handling
Bad fuel economy
If your tires have too much air (overinflation), 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 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 7,500 miles (12,500 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 Is Time
for New Tires on page
5-58 and Wheel Replacement
on page
5-61 for more information.
Make sure the spare tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If
it moves,
use the wheel wrench and jack handle extensions
to
tighten the cable. See Changing a Flat Tire on
page 5-63.
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 “Part
A: Scheduled
Maintenance Services,” in Section
6, for scheduled
rotation intervals.
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When rotating your tires, always use the correct rotation
pattern shown here.
Don’t include the spare tire in your tire rotation.
After the tires have been rotated, adjust the front and
rear inflation pressures as shown on the
Certificationnire label. Make certain that all wheel nuts
are properly tightened. See “Wheel Nut Torque”
under Capacities and Specifications on page
5-96.
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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While the tires available on General Motors passenger
cars and light trucks may vary with respect
to these
grades, they must also conform
to federal safety
requirements and additional General Motors Tire
Performance Criteria (TPC) standards.
Treadwear
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
(1.5) 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 - AA, A, 6, C
The traction grades, from highest to lowest, are AA, A,
B, and C. Those grades 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 straight-ahead braking
traction tests, and does not include acceleration,
cornering, hydroplaning, or peak traction characteristics.
Temperature - A, B, C
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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Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory
to give you the longest tire life
and best overall performance.
Scheduled wheel alignment and wheel balancing are
not needed. However,
if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need
to be reset. If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need
to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded.
If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts should be replaced.
If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer
if any of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new
GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
for your vehicle. Using the wrong replacement wheels, wheel
bolts or wheel nuts on your vehicle can be
dangerous. It could affect the braking and handling
of your vehicle, make your tires lose
air and make you lose control. You could have
a collision in which you or others could be
injured. Always use the correct wheel, wheel
bolts and wheel nuts for replacement.
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 on page 5-63 for more
information.
5-6 1

If a Tire Goes Flat
It’s unusual for a tire to “blowout” while you’re driving,
especially
if you maintain your tires properly. If air goes
out
of a tire, it’s much more likely to ieak out siowiy.
But if you should ever have a “blowout”, here are a few
tips about what
to expect and what to do:
If a front tire fails, the flat tire will create a drag that
pulls the vehicle toward that side. Take your foot
off the
accelerator pedal and grip the steering wheel firmly.
Steer to maintain lane position, and then gently brake
to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you’d use
in a skid.
In any rear blowout, remove your foot from the
accelerator pedal. Get the vehicle under control by
steering the way you want the vehicle
to go. It may be
very bumpy and noisy, but you can still steer. Gently
brake to a stop
- well off the road if possible.
If a tire goes flat, the next part shows how to use your
jacking equipment to change a flat tire safely.
Changing a Flat Tire
If a tire goes flat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your
hazard warning
fi hers.
Changing a tire can cause an injury. The
vehicle can slip
off the jack and roll over you
or other people. You and they could be badly injured. Find a level place to change your tire.
To help prevent the vehicle from moving:
1. Set the parking brake firmly.
2. Put the shift lever in PARK (P).
3. Turn off the engine.
4. Put the wheel blocks at the front and rear
of the tire farthest away from the one
being changed. That would be the tire on
the other side
of the vehicle, at the
opposite end.
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1
3. Insert the hoist end
(open end)
(F) of the
extension through
the hole
(G) in the rear
bumper.
Be sure the hoist end of the extension connects
into the hoist shaft (E). The ribbed square end
of the extension
is used to lower the spare tire.
4. Turn the wheel wrench (H) counterclockwise to
lower the spare tire to the ground. Continue to
turn the wheel wrench until the spare tire can be
pulled out from under the vehicle.
II
5. The wheel wrench has
a hook that allows you
to pull the hoist
cable towards you
to
assist in reaching
the spare tire.
6. When the tire has been
lowered, tilt the
retainer
(D) at the end
of the cable so it
can be pulled up
through the wheel
opening.
7. Put the spare tire near the flat tire.
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Removing the Flat Tire and Installing
the Spare Tire
Use the following pictures and instructions to remove
the flat tire and raise the vehicle.
1. Remove the center cap by placing the chisel end of
the wheel wrench in the slot on the wheel and
gently prying the cap out.
The
tools you’ll be using include the bottle jack (A), the
wheel blocks
(B), the jack handle (C), the jack handle
extensions
(D), and the wheel wrench (E).
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3. Position the jack under the vehicle.
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even
make the vehicle fall.
To help avoid personal
injury and vehicle damage, be sure to fit the
jack lift head into the proper location before
raising the vehicle.
Front Position
Front Tire Flat:
If the flat tire is on a front tire of
the vehicle,
you’ll need to use the jack handle (C)
and only one jack handle extension (D). Attach
the wheel wrench
to the jack handle extension.
Attach the jack handle
to the jack. Position the jack
on the frame behind the flat tire where the frame
sections overlap. Turn the wheel wrench clockwise
to raise the vehicle. Raise the vehicle far enough
off the ground so there is enough room for the spare
tire
to clear the ground.
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