2002 GMC SIERRA spare tire

5-32
6. Make sure the tire is stored securely. Push, pull, and
then try to rotate or turn the tire. If the tire moves,
use the wheel wrench/hoist shaft to tighten the cable.
Replace the jack, tools and spare tire lock.
Spare Tire
Your vehicle, when new, had a fully inflated spare tire.
A spare tire may lose air over time, so check its inflation
pressure regularly. See ªInflation
-Tire Pressureº and
ªLoading Your Vehicleº in the Index for information
regarding proper tire inflation and loading your vehicle.
For instruction on how to remove, install or store a spare
tire, see ªChanging a Flat Tireº in the Index.
After installing the spare tire on your vehicle, you
should stop as soon as possible and make sure the spare
is correctly inflated. Have the damaged or flat road tire
repaired or replaced as soon as you can and installed
back onto your vehicle. This way, a spare tire will be
available in case you need it again.
If your vehicle has a spare tire that does not match your
vehicle's original road tires and wheels in size and type,
do not include the spare in the tire rotation.

6-48 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. ªColdº 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)
NOTICE: (Continued)
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.

6-49 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 ªWhen It's
Time for New Tiresº and ªWheel Replacementº later in
this section 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/hoist shaft to
tighten the cable. See ªStoring a Flat or Spare Tire and
Toolsº in the Index.
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 ªScheduled Maintenance Servicesº in
the Index 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 ªWheel Nut Torqueº in
the Index.
CAUTION:
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
ªChanging a Flat Tireº in the Index.

6-51
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 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 rim flanges 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.

6-52 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 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
-- 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.

7-16
Part B: Owner Checks and Services
Listed in this part 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
It is important for you or a service station attendant to
perform these underhood checks at each fuel fill.
Engine Oil Level Check
Check the engine oil level and add the proper oil
if necessary. See ªEngine Oilº in the Index for
further details.Engine Coolant Level Check
Check the engine coolant level and add DEX
-COOL

coolant mixture if necessary. See ªEngine Coolantº in
the Index for further details.
Windshield Washer Fluid Level Check
Check the windshield washer fluid level in the
windshield washer tank and add the proper fluid if
necessary. See ªWindshield Washer Fluidº in the
Index for further details.
At Least Once a Month
Tire Inflation Check
Make sure tires are inflated to the correct pressures.
Don't forget to check your spare tire. See ªTiresº in the
Index for further details.
Cassette Deck Service
Clean cassette deck. Cleaning should be done every
50 hours of tape play. See ªAudio Systemsº in the
Index for further details.

7-17 At Least Twice a Year
Restraint System Check
Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors and anchorages are
working properly. Look for any other loose or damaged
safety belt system parts. If you see anything that might
keep a safety belt system from doing its job, have it
repaired. Have any torn or frayed safety belts replaced.
Also look for any opened or broken air bag coverings,
and have them repaired or replaced. (The air bag system
does not need regular maintenance.)
Wiper Blade Check
Inspect wiper blades for wear or cracking. Replace blade
inserts that appear worn or damaged or that streak or
miss areas of the windshield. Also see ªWiper Blades,
Cleaningº in the Index.Spare Tire Check
At least twice a year, after the monthly inflation check
of the spare tire determines that the spare is inflated to
the correct tire inflation pressure, make sure that the
spare tire is stored securely. Push, pull, and then try to
rotate or turn the tire. If it moves, use the wheel
wrench/ratchet to tighten the cable. See ªStoring the
Spare Tire and Toolsº in the Index.
Engine Air Cleaner Filter Restriction
Indicator Check
Your vehicle has an indicator located on the air cleaner
in the engine compartment that lets you know when the
air cleaner filter is dirty and needs to be changed. Check
indicator at least twice a year or when your engine oil is
changed, whichever occurs first. See ªAir Cleanerº in
the Index for more information. Inspect your air cleaner
filter restriction indicator more often if the vehicle is
used in dusty areas or under off road conditions.

8-6
Roadside Assistance
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 Change: 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 $5.00) will
be covered.
Jump Start: No
-start situations which require a battery
jump start will be covered at no charge.
Lock 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.
Trip Routing: Custom
-made, computerized highlighted
maps using the most direct or scenic route are provided
free of charge. Maps include points of interest and a list
of GMC dealers along the route. Also included is a list
of hotels along the route that are discounted through
affiliation with ªQuest International.º Trip Routing
is available through Roadside Assistance by calling
1
-800-GMC-8782 (462-8782). Please be prepared
to provide your Vehicle Identification Number (VIN).
Allow five working days for fulfillment.