maintenance GMC SIERRA 1998 User Guide

Install the new filter by pushing it all the way to the stop
on the duct.
Install the duct and the filter into the air cleaner housing.
Make sure that the duct fits properly into the housing.
Install the cover and fasten the two retaining clips.
After the air filter
is properly serviced, the indicator
should be reset. Push the button on top
of the indicator
to reset it to the green (clean) filter
zone.
Refer to the Maintenance Schedule to determine when to
replace the air filter. See “Owner Checks and Services”
in the Index.
A CAUTION:
Operating the engine with the air cleaner off can
cause you or others
to be burned. The air cleaner
not only cleans the air, it stops flame if the engine
backfires.
If it isn’t there, and the engine
backfires, you could be burned. Don’t drive with
it
off, and be careful working on the engine with
the air cleaner off.
I NOTICE:
If the air cleaner is off, a backfire can cause a
damaging engine fire. And, dirt can easily get
into your engine, which will damage it. Always
have the air cleaner in place when you’re driving.
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Automatic Transmission Fluid
If your vehicle has a diesel engine, see “Automatic
Transmission Fluid”
in the Diesel Supplement.
When to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change both the fluid and filter every
50,000 miles
(83
000 km) if the vehicle’s GVWR is over 8,600 or
if the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
regularly
reaches
90°F (32°C) or higher.
If your vehicle’s GVWR is not over 8,600 and you do not
use your vehicle under any
of these conditions, change the
fluid and filter every
100,000 miles (166 000 km).
See “Scheduled Maintenance Services’’ in the Index.
How to Check
Because this operation can be a little difficult, you
may choose to have this done at your
GM 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 little fluid can damage your
transmission.
Too much can mean that some of
the fluid could come
out and fall on hot engine
parts or exhaust system parts, starting a fire.
Be
sure to get an accurate reading if you check your
transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid 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, the fluid should be at normal
operating temperature, which is
180°F to 200°F (82°C
to 93°C). See “Checking Transmission Fluid Hot“ in
the Index.
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3. Check both sides of the dipstick, and read the lower
level. The fluid level must be in the COLD area for a
cold check or in the
HOT area or cross-hatched area
for a
hot check.
4. If the fluid level is in the acceptable range, push the
dipstick back in all the way; then flip the handle
down
to lock the dipstick in place.
io dd Fluid
Refer to the Maintenance Schedule to determine what
kind
of transmission fluid to use. See “Recommended
Fluids and Lubricants”
in the Index. Add
fluid only after checking the transmission fluid
while
it is hot. (A cold check is used only as a
reference.)
If the fluid level is low, add only enough of
the proper fluid
to bring the level up to the HOT area for
a hot check. It doesn’t take much fluid, generally less
than one pint
(0.5 L). Don’t overfill.
I NOTICE:
We recommend you use only fluid labeled
DEXRON@-111, because fluid with that label is
made especially for your automatic transmission.
Damage caused by fluid other than DEXRON-111
is not covered by your new vehicle warranty.
After adding fluid, recheck the fluid level as
described under “How to Check.”
When the correct fluid level is obtained, push the
dipstick back
in all the way; then flip the handle
down to lock the dipstick
in place.
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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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Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does
not mean something is wrong with
your brakes.
Properly torqued wheel
nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly torque wheel nuts
in the
proper sequence to
GM specifications.
If you have rear drum brakes, they don‘t have wear
indicators, but if you ever hear a rear brake rubbing
noise, have the rear brake linings inspected immediately. Also, the rear brake drums should be removed and
inspected each time the tires are removed for rotation
or
changing. When you have the front brake pads replaced,
have the rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
See “Brake System Inspection”
in Section 7 of this manual
under
Part C “Periodic Maintenance Inspections.”
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or
if there is a rapid increase in pedal
travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
If your brake pedal goes down farther than normal, your
rear drum brakes may need adjustment. Adjust them by
backing
up and firmly applying the brakes a few times.
Replacing Brake System Parts
The braking system on a modern 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 have
to have 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.
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4. Push in gently on the
bulb, turn it to the
left and remove it from
the socket. Windshield Wiper Blade Replacement
For proper type and length, see “‘Normal Maintenance 1 I
Replacement Parts” in the Index. I i
i
5. Put in a new bulb and, pushing in gently, turn it to
the right until it is tight.
6. Put the socket back in the lamp assembly and replace
the lens and lens seal.
To replace the windshield wiper blade assembly:
1. Lift the wiper arm and rotate the blade until it is
2. Push the release lever and slide the wiper assembly
3. Install a new blade by reversing Steps 1 and 2.
facing away from the windshield.
toward the driver’s side
of the vehicle.
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