2003 GMC SONOMA maintenance schedule

Brakes
Brake Fluid
Your brake master cylinder reservoir isfilled with DOT-3
brakefluid. SeeEngine Compartment Overview on
page 5-10for the location of the reservoir.
There are only two reasons why the brakefluid level in
the reservoir might go down. Thefirst is that the
brakefluid goes down to an acceptable level during
normal brake lining wear. When new linings are put in,
thefluid level goes back up. The other reason is
thatfluid is leaking out of the brake system.If it is, you should have your brake systemfixed, since
a leak means that sooner or later your brakes won’t
work well, or won’t work at all.
So, it isn’t a good idea to“top off”your brakefluid.
Adding brakefluid won’t correct a leak. If you addfluid
when your linings are worn, then you’ll have too
muchfluid when you get new brake linings. You should
add (or remove) brakefluid, as necessary, only when
work is done on the brake hydraulic system.
{CAUTION:
If you have too much brakeuid, it can spill on
the engine. Theuid will burn if the engine is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
uid only when work is done on the brake
hydraulic system. See“Checking Brake Fluid”
in this section.
Refer to the Maintenance Schedule to determine when
to check your brakefluid. SeePart C: Periodic
Maintenance Inspections on page 6-31.
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Rear Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change it. See
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’ll need to add some lubricant. 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. SeePart D: Recommended
Fluids and Lubricants on page 6-33.
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Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. However, there are two additonal systems that
need lubrication.
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. SeePart C: Periodic
Maintenance Inspections on page 6-31.
How to Check Lubricant
To get and accurate reading, the vehicle should be on
a level service.
If the level is below the bottom of thefiller plug hole, you’ll
need to add some lubricant. Remove the plug and add
enough lubricant to raise the level to the bottom of the
filler plug hole. Use care not to overtighten the plug.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeePart D: Recommended
Fluids and Lubricants on page 6-33.
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Front Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change it. See
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 1/2 inch (12 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. SeePart D: Recommended
Fluids and Lubricants on page 6-33.
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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. SeeWhen It Is Time
for New Tires on page 5-61andWheel Replacement
on page 5-65for 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 to tighten the cable. See
Changing a Flat Tire on page 5-68.
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 one of the correct
rotation patterns shown here.
If your vehicle has a compact spare tire or a spare tire
that does not match your vehicle’s regular road tires
and wheels in size and type, do not include the spare
in the tire rotation.
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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
Selecting the Right Schedule...........................6-5
Short Trip/City Scheduled Maintenance..............6-7
Long Trip/Highway Scheduled Maintenance......6-18
Part B: Owner Checks and Services................6-26
At Each Fuel Fill..........................................6-26
At Least Once a Month.................................6-26
At Least Twice a Year...................................6-26At Least Four Times a Year...........................6-27
At Least Once a Year...................................6-28
Part C: Periodic Maintenance Inspections.........6-31
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection............................6-31
Exhaust System Inspection............................6-31
Fuel System Inspection..................................6-31
Engine Cooling System Inspection...................6-31
Throttle System Inspection.............................6-32
Transfer Case and Front Axle (Four-Wheel
Drive) Inspection.......................................6-32
Brake System Inspection................................6-32
Part D: Recommended Fluids and Lubricants. . . .6-33
Part E: Maintenance Record...........................6-35
Section 6 Maintenance Schedule
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Maintenance Schedule
Introduction
Important: Keep engine oil at the proper level and
change as recommended.
Have you purchased the GM Protection Plan? The Plan
supplements your new vehicle warranties. See your
Warranty and Owner Assistance booklet or your dealer
for details.
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment. Improper vehicle maintenance can
even affect the quality of the air we breathe. Improper
fluid levels or the wrong tire inflation can increase
the level of emissions from your vehicle. To help protect
our environment, and to keep your vehicle in good
condition, be sure to maintain your vehicle properly.
Maintenance Requirements
Maintenance intervals, checks, inspections and
recommended fluids and lubricants as prescribed in this
manual are necessary to keep your vehicle in good
working condition. Any damage caused by failure
to follow scheduled maintenance may not be covered
by warranty.
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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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