tire GMC YUKON 2003 Workshop Manual

{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rimanges 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.
Uniform Tire Quality Grading
Quality grades can be found where applicable on the
tire sidewall between tread shoulder and maximum
section width. For example:
Treadwear 200 Traction AA Temperature A
The following information relates to the system
developed by the United States National Highway
Traffic Safety Administration, which grades tires by
treadwear, traction and temperature performance. (This
applies only to vehicles sold in the United States.)
The grades are molded on the sidewalls of most
passenger car tires. The Uniform Tire Quality Grading
system does not apply to deep tread, winter-type
snow tires, space-saver or temporary use spare tires,
tires with nominal rim diameters of 10 to 12 inches
(25 to 30 cm), or to some limited-production tires.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, B, 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.
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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.
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.
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{CAUTION:
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 or tire chain
clearance to the body and chassis.
SeeChanging a Flat Tire on page 5-69for more
information.
Used Replacement Wheels
{CAUTION:
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 a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
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Tire Chains
{CAUTION:
If your vehicle has P265/75R16, LT265/75R16,
P265/70R16 or P265/70R17 size tires, don’t use
tire chains. They can damage your vehicle
because there’s not enough clearance. Tire
chains used on a vehicle without the proper
amount of clearance can cause damage to the
brakes, suspension or other vehicle parts. The
area damaged by the tire chains could cause
you to lose control of your vehicle and you or
others may be injured in a crash.
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 dond traction devices that willt,
install them on the rear tires.Notice:If you have a tire size other than P265/75R16,
LT265/75R16, P265/70R16 or P265/70R17 use tire
chains only where legal and only when you must. Use
chains that are the proper size for your tires. Install
them on the rear tires only.
Don’t use chains on the front tires.
Tighten them as tightly as possible with the ends
securely fastened. Drive slowly and follow the chain
manufacturer’s instructions. If you can hear the
chains contacting your vehicle, stop and retighten
them. If the contact continues, slow down until
it stops. Driving too fast or spinning the wheels with
chains on will damage your vehicle.
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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 leak out slowly.
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, theflat tire will create a drag that
pulls the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheelfirmly.
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 goesflat, the next part shows how to use your
jacking equipment to change aflat tire safely.
Changing a Flat Tire
If a tire goesflat, avoid further tire and wheel damage
by driving slowly to a level place. Turn on your
hazard warningflashers.
{CAUTION:
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 brakermly.
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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The following steps will tell you how to use the jack and
change a tire.
Removing the Spare Tire and Tools
A. Tool Kit with Jack Tools and Gloves
B. Retaining Bracket and Wing Nut
C. Wing Nut Holding Tire Blocks
D. Tire Blocks
E. Bottle Jack
Tahoe/Yukon (Rear Access Panel)
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A. Bottle Jack
B. Wheel Blocks
C. Wing Nut Holding
Tire Blocks
D. Mounting Bracket
E. Removable TrayF. Retaining Hook
G. Retaining Bracket
and Wing Nut
H. Tool Kit with Jack
Tools and GlovesFor Tahoe/Yukon, the equipment is located behind the
left trim panel in the rear of the vehicle. Unlatch the
release lever to open the trim panel door. Skip thefirst
step and follow the last three.
For Suburban/Yukon XL, the equipment you’ll need is
under the storage tray in the left trim panel.
1. Remove the tray to access the tools.
2. There is a wing nut used to retain the tool kit. To
remove it, turn the wing nut counterclockwise.
3. To release the bottle jack from its holder, turn the
knob on the bottle jack counterclockwise to lower
the jack head.
4. The wheel blocks and the wheel block retainer can
be removed by turning the wing nut
counterclockwise.
You’ll use the jack handle extensions and the wheel
wrench to remove the underbody-mounted spare tire. Suburban/Yukon XL
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A. Spare Tire (Valve
Stem Pointed
Down)
B. Hoist Assembly
C. Hoist Cable
D. Tire Retainer
E. Hoist Shaft
F. Hoist End of
Extension ToolG. Hoist Shaft Access
Hole
H. Wheel Wrench
I. Jack Handle
Extensions
J. Hoist Lock (If
Equipped)1. If your vehicle is equipped with a hoist lock (J),
open the spare tire lock cover on the bumper
and use the ignition key to remove the lock.
2. Assemble the wheel wrench (H) and the two jack
handle extensions (I) as shown.
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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 to
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.
If the spare tire does not lower to the ground, the
secondary latch is engaged causing the tire
not to lower. See“Secondary Latch System”later in
this section.5. The wheel wrench has
a hook that allows you
to pull the hoist
cable towards you to
assist in reaching
the spare tire.
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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 theflat tire.Removing the Flat Tire and Installing
the Spare Tire
Use the following pictures and instructions to remove
theflat tire and raise the vehicle.
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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