2003 GMC SIERRA maintenance

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 denite 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’llnd 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
inated? Are theuid 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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After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis or under the hood. These
accumulations can be are hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires and exhaust
system for damage. Also, check the fuel lines and
cooling system for any leakage.
Your vehicle will require more frequent service due to
off-road use. Refer to the Maintenance Schedule
for additional information.
Driving at Night
Night driving is more dangerous than day driving.
One reason is that some drivers are likely to be
impaired—by alcohol or drugs, with night vision
problems, or by fatigue.
Here are some tips on night driving.
Drive defensively.
Don’t drink and drive.
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Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake and shift into PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmissionuid (don’t overll),
engine oil, axle lubricant, belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help yound them quickly. If
you’re trailering, it’s a good idea to review these sections
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
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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
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Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you’ll go to your dealer
for all your service needs. You’ll get genuine GM parts
and GM-trained and supported service people.
We hope you’ll want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
Doing Your Own Service Work
If you want to do some of your own service work, you’ll
want to use the proper service manual. It tells you
much more about how to service your vehicle than this
manual can. To order the proper service manual,
seeService Publications Ordering Information on
page 7-9.
Your vehicle has an air bag system. Before attempting
to do your own service work, seeServicing Your Air
Bag-Equipped Vehicle on page 1-70.
You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeePart E: Maintenance Record on page 6-17.
{CAUTION:
You can be injured and your vehicle could be
damaged ifyou try to do service work on a
vehicle without knowing enough about it.
•Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
CAUTION: (Continued)
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CAUTION: (Continued)
•
Be sure to use the proper nuts, bolts and
other fasteners. “English” and “metric”
fasteners can be easily confused. If you
use the wrong fasteners, parts can later
break or fall off. You could be hurt.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This may cause wind
noise and affect windshield washer performance.
Check with your dealer before adding equipment to the
outside of your vehicle.
Fuel
Use of the recommended fuel is an important part of the
proper maintenance of your vehicle.
Gasoline Octane
Use regular unleaded gasoline with a posted octane
of 87 or higher. If the octane is less than 87, you may
get a heavy knocking noise when you drive. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. Otherwise, you might damage
your engine. A little pinging noise when you accelerate
or drive uphill is considered normal. This does not
indicate a problem exists or that a higher-octane fuel is
necessary. If you are using 87 octane or higher-octane
fuel and hear heavy knocking, your engine needs
service.
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Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmissionfluid
level is when the engine oil is changed.
Change both thefluid andfilter every 50,000 miles
(83 000 km) if the vehicle is mainly driven under one or
more of these conditions:
•In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
•In hilly or mountainous terrain.
•When doing frequent trailer towing.
•Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change thefluid andfilter every
100,000 miles (166 000 km).
SeePart A: Scheduled Maintenance Services on
page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too littlefluid can damage
your transmission. Too much can mean that some
of thefluid could come out and fall on hot engine
part or exhaust system parts, starting afire.
Too littlefluid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmissionfluid.
Wait at least 30 minutes before checking the
transmissionfluid level if you have been driving:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic–especially in hot weather.
•While pulling a trailer.
To get the right reading, thefluid should be at normal
operating temperature, which is 180°Fto200°F
(82°Cto93°C).
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3. Check both sides of the dipstick, and read the lower
level. Thefluid level must be in the COLD area,
below the cross-hatched area, for a cold check or in
the HOT area or cross-hatched area for a hot
check.
4. If thefluid level is in the acceptable range, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmissionfluid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-15.
Addfluid only after checking the transmissionfluid while
it is hot. (A cold check is used only as a reference.) If
thefluid level is low, add only enough of the properfluid
to bring the level up to the HOT area for a hot check.
It doesn’t take muchfluid, generally less than one
pint (0.5 L).Don’t overfill.
Notice:We recommend you use onlyfluid labeled
DEXRON
®-III, becausefluid with that label is
made especially for your automatic transmission.
Damage caused byfluid other than DEXRON
®-III is
not covered by your new vehicle warranty.
•After addingfluid, recheck thefluid level as
described under“How to Check”.
•When the correctfluid level is obtained, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
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