1998 GMC SIERRA maintenance schedule

How to Add Fluid
Here’s how to add fluid. Refer to the Maintenance
Schedule to determine what kind of fluid to use. See
”Recommended Fluids and Lubricants”
in the Index.
1. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only enough
fluid to bring the tluid level up to the bottom of the
filler plug hole.
3. Install the filler plug.
Be sure the plug is fully seated.
Hydraulic Clutch
The hydraulic clutch system in your vehicle is
self-adjusting. A slight amount of play (1/4 inch to
1/2 inch or 6 lnm to 12 mm) in the pedal is normal.
It isn‘t a good idea to “top off’ your clutch fluid. Adding
fluid won’t correct a leak.
A fluid loss in this system could
indicate a problem. Have
the system inspected and repaired.
When to Check and What to Use
Refer to the Maintenance
Schedule, Owner Checks
and Services,
to determine
how often you should check
the fluid level
in your clutch
master cylinder reservoir
and for the proper fluid. See
“Owner Checks and
Services” and
“Recommended Fluids and
Lubricants” in the Index.
How to Check
The proper fluid should be added if the level does not
reach the bottom
of the diaphragm when it’s in place in
the reservoir. See the instructions on the reservoir cap.
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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
“Scheduled Maintenance Services” in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you’ll need to add some lubricant.
Add enough lubricant
to raise the level to the bottom
of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant
to use. See “Recommended Fluids and
Lubricants”
in the Index.
C3 (3500 HD) Trucks Equipped with Dana
Rear
Axle
Additional rear axle scheduled maintenance is required
on
3500 HD models equipped with Dana rear axles
when they are driven under the following conditions:
Extreme loading (at or near GVWR) or trailer
Operation above 45 mph (70 km/h) for extended
Vehicles used in any of these conditions require the
rear axle lubricant be changed every
30,000 miles
(50 000 km). Fluid capacity is 4.12 quarts (3.9 L).
towing, and:
periods of time.
Four-wheel Drive
Most lubricant checks in this section also apply to
four-wheel-drive vehicles. However, they have two
additional systems that need lubrication.
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Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check
the lubricant. See “Periodic Maintenance
Inspections” in the Index.
How to Check I>--’- --’ :::It
If the level is below the bottom of the filler plug hole,
you’ll need to add some lubricant. Add enough lubricant
to raise the level to the bottom of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants” in the Index.
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
“Scheduled Maintenance Services”
in the Index.
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How to Check Lubricant
If the level is below the bottom of the filler 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
mrn) below the filler
plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level to the
bottom
of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants” in the Index.
Engine Coolant
The cooling s stem in your vehicle is filled with
DEX-COOL engine coolant. This coolant is designed
~
to remain in your vehicle for 5 years or 150,000 miles I
(240 000 km) whichever occurs first, if you add only ~
DEX-COOL’ extended life coolant.
8
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
i
with engine overheating, see “Engine Overheating” in 1
the Index.
A 50/50 mixture of water and DEX-COOL@ coolant will: 1
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 OF (1 29 O C).
Protect against rust and corrosion.
0 Help keep the proper engine temperature.
0 Let the warning gages work as they should.
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Brakes
Brake Fluid
Your brake master cylinder
reservoir is here. It
is filled
with DOT-3 brake fluid.
There are only two reasons why the brake fluid level
in the
reservoir might go down. The first is that the brake fluid
goes down to an acceptable level during normal brake
lining wear. When new linings are put
in, the fluid level
goes back up. The other reason is that fluid
is leaking out
of the brake system. If it is, you should have your brake
system fixed, 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 brake fluid.
Adding brake fluid won’t correct a leak.
If you add fluid
when your linings are worn, then you’ll
have too much
fluid when
you get new brake linings. You should add
(or remove) brake fluid,
as necessary, only when work is
done
on the brake hydraulic system.
- - -
4 CAU-ION:
If you have too much brake fluid, it can spill on the
engine. The fluid
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.
Refer to the Maintenance Schedule to determine when to
check your brake fluid. See “Periodic Maintenance
Inspections” in the Index.
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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.
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 “When It‘s Time for New Tires” and
“Wheel Replacement” later in this section for more
information. If your vehicle has dual rear wheels, also
see “Dual Tire Operation” later
in this section. 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 “Scheduled
Maintenance Services”
in the Index for scheduled
rotation intervals.
1
FRT FRT
[x[
If your vehicle has single rear wheels, always use one of
the correct rotation patterns shown here when rotating
your tires.
If your vehicle has front tires with different load ranges
or tread designs (such as all season vs. on/off road) than
the rear tires, don’t rotate your tires front
to rear.
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Section 7 Maintenance Sch - dulp
This section covers the maintenance required for your vehicle. Your vehicle needs these services to retain its safety,
dependability and emission control performance.
7-2
7-4
7-5
7-5
7-6
7-7
Introduction
Part
A: Scheduled Maintenance Services
Short Trip/City Definition
Short Trip/City Intervals
Long Trip/Highway Definition
Long Trip/Highway Intervals 7-8
Short Trip/City Maintenance Schedule
7-28 Long Trip/Highway Maintenance Schedule
7-40 Part
B: Owner Checks and Services
7-44 Part C: Periodic Maintenance Inspections
7-46 Part
D: Recommended Fluids and Lubricants
7-49 Part
E: Maintenance Record
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LE
IMPORTANT-
KEEP ENGINE OIL
AT THE PROPER
,VEL AND CHANGE
RECOMMENDED
AS
Have you purchased the GM Protection Pl~rn? The Plan
supplements your new vehicle M:u-ranties. See your
Warranty and Owner Assistance booklet,
or your GM
dealer-for details.
Introduction
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle in good working condition, but also helps the
environment.
All recommended maintenance procedures
are important. 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, please maintain your vehicle properly.
How This Section is Organized
The remainder of this section is divided into five parts:
“Part A: Scheduled Maintenance Services” shows
what to have done and how often. Some
of these
services can be complex,
so unless YOLI are technically
qualified and have the necessary equipment, you should
let
your dealer‘s service department or another qualified
service center do these
jobs.
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