2003 GMC SIERRA maintenance

Brakes
Brake Fluid
Your brake master cylinder reservoir isfilled with DOT-3
brakefluid. SeeEngine Compartment Overview on
page 5-12for 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 brakefluid, it can spill on
the engine. Thefluid will burn if the engine is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
fluid 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 6-14.
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Replacing Brake System Parts
The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your
vehicle was designed and tested with top-quality GM
brake parts. When you replace parts of your braking
system–for example, when your brake linings
wear down and you need new ones put in–be sure
you get new approved GM replacement parts.
If you don’t, your brakes may no longer work properly.
For example, if someone puts in brake linings that
are wrong for your vehicle, the balance between your
front and rear brakes can change—for the worse.
The braking performance you’ve come to expect can
change in many other ways if someone puts in the
wrong replacement brake parts.
Battery
Your new vehicle comes with a maintenance free
ACDelco®battery. When it’s time for a new battery, get
one that has the replacement number shown on the
original battery’s label. We recommend an ACDelco
®
battery. SeeEngine Compartment Overview on
page 5-12for battery location.
Warning:Battery posts, terminals and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
Vehicle Storage
If you’re not going to drive your vehicle for 25 days or
more, remove the black, negative (−) cable from
the battery. This will help keep your battery from
running down.
{CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
aren’t careful. See“Jump Starting”next for
tips on working around a battery without
getting hurt.
Contact your dealer to learn how to prepare your
vehicle for longer storage periods.
Also, for your audio system, seeTheft-Deterrent
Feature on page 3-75.
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All-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. However, there are two additional 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 6-14.
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.
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 6-15.
(A) Fill Plug (B) Drain Plug
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Rear Axle
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. SeePart 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.The proper level is from 5/8 inch to 1 5/8 inch (15 mm to
40 mm) below the bottom of thefiller plug hole. Add
only enoughfluid to reach the proper level. The proper
level for vehicles with QUADRASTEER™(4 Wheel
Steer) is from 0 to 1/4 inch (0 to 6 mm) below thefiller
plug hole. Add only enoughfluid to reach the proper
level.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. SeePart D: Recommended
Fluids and Lubricants on page 6-15.
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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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Cleaning Aluminum or Chrome-Plated
Wheels
Your vehicle may be equipped with either aluminum or
chrome-plated wheels.
Keep your wheels clean using a soft clean cloth with
mild soap and water. Rinse with clean water. After
rinsing thoroughly, dry with a soft clean towel. A wax
may then be applied.
The surface of these wheels is similar to the painted
surface of your vehicle. Don’t use strong soaps,
chemicals, abrasive polishes, abrasive cleaners,
cleaners with acid, or abrasive cleaning brushes on
them because you could damage the surface. Do not
use chrome polish on aluminum wheels.
Use chrome polish only on chrome-plated wheels, but
avoid any painted surface of the wheel, and buff off
immediately after application.
Don’t take your vehicle through an automatic car wash
that has silicone carbide tire cleaning brushes. These
brushes can also damage the surface of these wheels.
Cleaning Tires
To clean your tires, use a stiff brush with tire cleaner.
Notice:When applying a tire dressing, always take
care to wipe off any overspray or splash from all
painted surfaces on the body or wheels of the
vehicle. Petroleum-based products may damage the
paintfinish and tires.
Sheet Metal Damage
If your vehicle is damaged and requires sheet metal
repair or replacement, make sure the body repair shop
applies anti-corrosion material to parts repaired or
replaced to restore corrosion protection.
Original manufacturer replacement parts will provide the
corrosion protection while maintaining the warranty.
Finish Damage
Any stone chips, fractures or deep scratches in the
finish should be repaired right away. Bare metal
will corrode quickly and may develop into major repair
expense.
Minor chips and scratches can be repaired with touch-up
materials avaliable from your dealer. Larger areas of
finish damage can be corrected in your dealer’s
body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody. If these are not
removed, accelerated corrosion (rust) can occur on
the underbody parts such as fuel lines, frame,floor pan
and exhaust system even though they have corrosion
protection.
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