
Your vehicle has one
double-sided key for the
ignition and all door
locks as well as the spare
tire hoist lock, if equipped.
If you ever lose your keys, your dealer will be able to
assist you with obtaining replacements.
Notice:Your vehicle has a number of features that
can help prevent theft. You can have a lot of
trouble getting into your vehicle if you ever lock
your keys inside. You may even have to damage
your vehicle to get in. So be sure you have
spare keys.
If you ever do get locked out of your vehicle, call the
GM Roadside Assistance Center. SeeRoadside
Assistance Program on page 7-5. If your vehicle is
equipped with the OnStar
®system with an active
subscription and you lock your keys inside the vehicle,OnStar
®may be able to send a command to unlock
your vehicle. SeeOnStar®System on page 2-33
for more information.
Remote Keyless Entry System
Your keyless entry system operates on a radio
frequency subject to Federal Communications
Commission (FCC) Rules and with Industry Canada.
This device complies with Part 15 of the FCC Rules.
Operation is subject to the following two conditions:
1. This device may not cause interference, and
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
This device complies with RSS-210 of Industry Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference, and
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modi cations to this system by other than
an authorized service facility could void authorization to
use this equipment.
2-3
2003 - Sierra Denali 

Operating Your All-Wheel-Drive
Vehicle Off Paved Roads
Many of the same design features that help make your
vehicle responsive on paved roads during poor
weather conditions—features like the locking rear axle
and all-wheel drive—help make it much better
suited for off-road use than a conventional passenger
car. Its higher ground clearance also helps your vehicle
step over some off-road obstacles. But your vehicle
doesn’t have features like special underbody shielding
and a transfer case low gear range, things that are
usually thought necessary for extended or severe
off-road service. This guide is for operating your vehicle
off paved roads.
Also, seeBraking on page 4-5.
Off-road driving can be great fun. But it does have
some de nite hazards. The greatest of these is
the terrain itself.
“Off-roading”means you’ve left the great North American
road system behind. Traffic lanes aren’t marked.
Curves aren’t banked. There are no road signs.
Surfaces can be slippery, rough, uphill or downhill.
In short, you’ve gone right back to nature.Off-road driving involves some new skills. And that’s
why it’s very important that you read this guide.
You’ll nd many driving tips and suggestions. These will
help make your off-road driving safer and more
enjoyable.
Before You Go Off-Roading
There are some things to do before you go out.
For example, be sure to have all necessary maintenance
and service work done. Check to make sure all
underbody shields (if so equipped) are properly
attached. Is there enough fuel? Is the spare tire fully
in ated? Are the uid levels up where they should be?
What are the local laws that apply to off-roading
where you’ll be driving? If you don’t know, you should
check with law enforcement people in the area. Will you
be on someone’s private land? If so, be sure to get
the necessary permission.
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2003 - Sierra Denali 

Tires..............................................................5-56
Inflation -- Tire Pressure................................5-57
Tire Inspection and Rotation...........................5-58
When It Is Time for New Tires.......................5-59
Buying New Tires.........................................5-60
Uniform Tire Quality Grading..........................5-61
Wheel Alignment and Tire Balance..................5-62
Wheel Replacement......................................5-62
Tire Chains..................................................5-64
If a Tire Goes Flat........................................5-64
Changing a Flat Tire.....................................5-65
Spare Tire...................................................5-82
Appearance Care............................................5-82
Cleaning the Inside of Your Vehicle.................5-83
Care of Safety Belts......................................5-84
Weatherstrips...............................................5-85
Cleaning the Outside of Your Vehicle..............5-85Sheet Metal Damage.....................................5-87
Finish Damage.............................................5-87
Underbody Maintenance................................5-87
Chemical Paint Spotting.................................5-88
GM Vehicle Care/Appearance Materials...........5-88
Vehicle Identification......................................5-90
Vehicle Identification Number (VIN).................5-90
Service Parts Identification Label.....................5-90
Electrical System............................................5-91
Add-On Electrical Equipment..........................5-91
Windshield Wiper Fuses................................5-91
Power Windows and Other Power Options.......5-91
Fuses and Circuit Breakers............................5-91
Capacities and Specifications..........................5-99
Capacities and Specifications.........................5-99
Normal Maintenance Replacement Parts
.........5-100
Section 5 Service and Appearance Care
5-2
2003 - Sierra Denali 

CAUTION: (Continued)
•
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 Certification/Tire label, which is on the rear edge of
the driver’s door, 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 muchflexing
•Too much heat
•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.
5-57
2003 - Sierra Denali 

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. SeeWhen It Is Time
for New Tires on page 5-59andWheel Replacement
on page 5-62for 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. SeeChanging a Flat Tire on
page 5-65.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. Thefirst rotation
is the most important. See“Part A: Scheduled
Maintenance Services,”in Section 6, for scheduled
rotation intervals.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
Certification/Tire label. Make certain that all wheel nuts
are properly tightened. See“Wheel Nut Torque”
underCapacities and Specifications on page 5-99.
5-58
2003 - Sierra Denali 

Buying New Tires
Tofind out what kind and size of tires you need, look at
the Certification/Tire label.
The tires installed on your vehicle when it was new had
a Tire Performance Criteria Specifications (TPC
Spec) number on each tire’s sidewall. When you get
new tires, get ones 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, 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
CAUTION: (Continued)
CAUTION: (Continued)
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. If your vehicle has 17 inch road tires
(those originally installed on your vehicle) it is
all right to drive with the 16 inch spare tire that
came with your vehicle. When new, your vehicle
included a spare tire and wheel assembly with
the same overall diameter as your vehicle’s
road tires and wheels. Because this spare tire
was developed for use on your vehicle, it will
not affect vehicle handling or cause damage to
your vehicle.
{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rimflanges 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.
5-60
2003 - Sierra Denali 

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.
5-61
2003 - Sierra Denali 

Removing the Spare Tire and Tools
The equipment you’ll need is under the passenger’s
side second row seat. The spare tire is located
underneath the vehicle.
1. Pull up the second row seat with the loop at the
base of the seat cushion to access the tools.
2. The wheel blocks and the wheel block retainer can
be removed by turning 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 slightly.4. There is also a wing nut used to retain the storage
bag and tools. To remove it, turn the wing nut
counterclockwise.
You’ll use the jack handle extensions and the wheel
wrench to remove the underbody-mounted spare tire.
A. Spare Tire (Valve Stem Pointed Down)
B. Hoist Assembly
C. Hoist Cable
D. Tire Retainer
E. Hoist Shaft
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2003 - Sierra Denali