service GMC SIERRA 2003 Repair Manual

Front Axle
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. See Part A:Part A:
Scheduled Maintenance Services on page 6-4.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.If the level is below the bottom of thefiller plug hole,
you may need to add some lubricant.
When the differential is cold, add enough lubricant to
raise the level to 0 to 3/8 inch (9.5 mm) below thefiller
plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level to the
bottom of thefiller plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See Part D:Part D:
Recommended Fluids and Lubricants on page 6-15.
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Windshield Wiper Blade
Replacement
Windshield wiper blades should be inspected at least
twice a year for wear and cracking. SeeAt Least Twice
a Year on page 6-10for more information.
Replacement blades come in different types and are
removed in different ways. For proper type and length,
seeNormal Maintenance Replacement Parts on
page 5-100.To replace the windshield wiper blade assembly do the
following:
1. Lift the wiper arm and turn the blade until it is
facing away from the windshield.
2. Push the release lever and slide the wiper assembly
toward the driver’s side of the vehicle.
3. Install a new blade by reversing Steps 1 and 2.
Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer. If you ever have questions
about your tire warranty and where to obtain service,
see your GMC Warranty booklet for details.
{CAUTION:
Poorly maintained and improperly used tires
are dangerous.
•Overloading your tires can cause
overheating as a result of too much
friction. You could have an air-out and a
serious accident. See“Loading Your
Vehicle”in the Index.
CAUTION: (Continued)
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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.
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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.
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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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Vehicle Identification
Vehicle Identification Number (VIN)
This is the legal identifier for your vehicle. It appears on
a plate in the front corner of the instrument panel, on
the driver’s side. You can see it if you look through the
windshield from outside your vehicle. The VIN also
appears on the Vehicle Certification and Service Parts
labels and the certificates of title and registration.
Engine Identification
The 8th character in your VIN is the engine code.
This code will help you identify your engine,
specifications and replacement parts.
Service Parts Identification Label
You’llfind this label located in the glove box. It’s very
helpful if you ever need to order parts. On this label is:
•your VIN,
•the model designation,
•paint information and
•a list of all production options and special
equipment.
Be sure that this label is not removed from the vehicle.
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Maintenance Schedule......................................6-2
Introduction...................................................6-2
Your Vehicle and the Environment....................6-2
Maintenance Requirements..............................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using Your Maintenance Schedule....................6-4
Scheduled Maintenance...................................6-5
Part B: Owner Checks and Services................6-10
At Each Fuel Fill..........................................6-10
At Least Once a Month.................................6-10
At Least Twice a Year...................................6-10At Least Once a Year
...................................6-11
Part C: Periodic Maintenance Inspections
.........6-14
Steering and Suspension Inspection
................6-14
Exhaust System Inspection
............................6-14
Fuel System Inspection
..................................6-14
Engine Cooling System Inspection
...................6-14
Transfer Case and Front Axle (All-Wheel
Drive) Inspection
.......................................6-15
Brake System Inspection
................................6-15
Part D: Recommended Fluids and Lubricants
. . . .6-15
Part E: Maintenance Record
...........................6-17
Section 6 Maintenance Schedule
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How This Section is Organized
This maintenance schedule is divided intofive parts:
“Part A: Scheduled Maintenance Services”explains
what to have done and how often. Some of these
services can be complex, so unless you are technically
qualified and have the necessary equipment, you
should let your GM dealer’s service department do these
jobs.
Your GM dealer has GM-trained and supported service
people that will perform the work using genuine GM
parts.
{CAUTION:
Performing maintenance work on a vehicle can
be dangerous. In trying to do some jobs, you
can be seriously injured. Do your own
maintenance work only if you have the
required know-how and the proper tools and
equipment for the job. If you have any doubt,
have a qualified technician do the work.
If you want to get the service information, seeService
Publications Ordering Information on page 7-9.“Part B: Owner Checks and Services”tells you what
should be checked and when. It also explains what
you can easily do to help keep your vehicle in good
condition.
“Part C: Periodic Maintenance Inspections”explains
important inspections that your dealer’s service
department can perform for you.
“Part D: Recommended Fluids and Lubricants”lists
some recommended products necessary to help
keep your vehicle properly maintained. These products,
or their equivalents, should be used whether you do
the work yourself or have it done.
“Part E: Maintenance Record”is a place for you to
record and keep track of the maintenance performed on
your vehicle. Keep your maintenance receipts. They
may be needed to qualify your vehicle for warranty
repairs.
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Part A: Scheduled Maintenance
Services
This part contains engine oil and chassis lubrication
scheduled maintenance which explains the engine oil life
system and how it indicates when to change the
engine oil andfilter. Lubricate chassis components with
each oil change. Also, listed are scheduled maintenance
services which are to be performed at the mileage
intervals specified.
Using Your Maintenance Schedule
We at General Motors want to help you keep your
vehicle in good condition. But we don’t know exactly how
you’ll drive it. You may drive very short distances only
a few times a week. Or you may drive long distances in
very hot, dusty weather. You may use your vehicle in
making deliveries. Or you may drive it to work, to
do errands or in many other ways.
Because of all the different ways people use their
vehicles, maintenance needs vary. You may need more
frequent checks and replacements. So please read
the following and note how you drive. If you have any
questions on how to keep your vehicle in good condition,
see your dealer.This part tells you the maintenance services you should
have done and when to schedule them.
When you go to your dealer for your service needs,
you’ll know that GM-trained and supported service
people will perform the work using genuine GM parts.
The properfluids and lubricants to use are listed in
Part D. Make sure whoever services your vehicle uses
these. All parts should be replaced and all necessary
repairs done before you or anyone else drives the
vehicle.
This schedule is for vehicles that:•carry passengers and cargo within recommended
limits. You willfind these limits on your vehicle’s
Certification/Tire label. SeeLoading Your Vehicle on
page 4-47.
•are driven on reasonable road surfaces within legal
driving limits.
•are driven off-road in the recommended manner.
SeeOperating Your All-Wheel-Drive Vehicle Off
Paved Roads on page 4-18.
•use the recommended fuel. SeeGasoline Octane
on page 5-4.
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Scheduled Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of
this vehicle. The services shown at 150,000 miles
(240 000 km) and 200,000 miles (332 000 km) should
be repeated at the same intervals after 150,000 miles
(240 000 km) and 200,000 miles (332 000 km) for the life
of this vehicle.
SeePart B: Owner Checks and Services on page 6-10
andPart C: Periodic Maintenance Inspections on
page 6-14.
Footnotes
†The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle ’s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
+A good time to check your brakes is during tire
rotation. See Brake System Inspection on page 6-15.
Engine Oil and Chassis Lubrication
Scheduled Maintenance
Change engine oil and filter as indicated by the GM
Oil Life System (or every 12 months, whichever
occurs first). Reset the system.
Your vehicle has a computer system that lets you know
when to change the engine oil andfilter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system to work
properly, you must reset the system every time the oil is
changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENGINE OIL message will
come on. Change your oil as soon as possible within
the next two times you stop for fuel. It is possible that,
if you are driving under the best conditions, the oil
life system may not indicate that an oil change is
necessary for over a year. However, your engine oil and
filter must be changed at least once a year and at
this time the system must be reset. Your dealer has
GM-trained service people who will perform this
work using genuine GM parts and reset the system.
It is also important to check your oil regularly and keep
it at the proper level.
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