1998 GMC SIERRA air condition

Be sure the posted octane is at least 87. If the octane is
less than
87, you may get a heavy knocking noise when
you drive. If it’s bad enough, it can damage your engine.
If you’re using fuel rated at 87 octane or higher and you
hear heavy knocking, your engine needs service. But
don’t worry if you hear a little pinging noise when
you’re accelerating or driving
up a hill. That’s norlnal,
and you don’t have to
buy a higher octane fuel to get rid
of pinging. It’s the heavy, constant knock that means
you have a problem.
If your vehicle is certified to meet California Emission
Standards (indicated on the underhood emission control
label),
it is designed to operate on fuels that meet
California specifications.
If such fuels are not available
in states adopting California emissions standards, your
vehicle will operate satisfactorily on fuels meeting
federal specifications, but emission control system
performance may be affected. The malfunction indicator lamp
on your instrument
panel may turn on and/or your
vehicle may fail
a smog-check test. If this occurs, return
to your authorized
GM dealer for diagnosis to determine
the cause
of’ fdilure. In the event it is determined that the
cause
of the condition is the type of fuels used, repairs
may not be covered by your warranty.
Some gasolines that are not reformulated for low
emissions contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT);
ask your service station operator whether or not his fuel
contains MMT. General Motors does not recommend the
use
of such gasolines. If fuels containing MMT are used,
spark plug life may be reduced and your emission
control system performance may be affected. The
malfunction indicator
lamp on your instrument panel
may
turn on. If this occurs, return to your authorized
GM dealer for service.
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Checking Things Under the Hood
I I A CAUTION:
If your vehicle has air conditioning, the auxiliary
engine fan under the hood can start up and
injure you even when the engine is not running.
Keep hands, clothing and tools away from any
underhood electric fan.
I
A CAUTION:
I
I
Things that burn can get on hot engine parts and
start a fire. These include liquids like gasoline or
diesel fuel, oil, coolant, brake fluid, windshield
washer and other fluids, and plastic or rubber.
You or others could be burned. Be careful not
to drop or spill things that
will burn onto a
hot engine.
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You need a new tire if any of the following statements
are true:
0 You can see the indicators at three or more places
around the tire.
You can see cord or fabric showing through the
tire’s rubber.
The tread or sidewall is cracked, cut or snagged deep
enough to show cord or fabric.
The tire has a bump, bulge or split.
The tire has a puncture, cut or other damage that
can’t be repaired well because of the size or location
of the damage.
Dual Tire Operation
When the vehicle is new, or whenever a wheel, wheel
bolt or wheel
nut is replaced, check the wheel nut
torque after 100, 1,000 and 6’000 miles (160, 1 600 and
10 000 km) of driving. For proper torque, see “Wheel
Nut Torque”
in the Index. The outer
tire
on a dual wheel setup generally wears
Faster than the inner tire. Your tires will wear more
evenly and last longer if
you rotate the tires periodically.
If you’re going to be doing a lot
of driving on
high-crown roads,
you can reduce tire wear by adding
5 psi (35 kPa) to the tire pressure in the outer tires. Be
sure to return to the recommended pressures when
no
longer driving under those conditions. See “Changing a
Flat Tire’’ in the Index for more information.
If you operate your vehicle with a tire that is badly
underinflated, the tire can overheat. An overheated
tire can lose air suddenly or catch fire.
You or
others could be injured. Be sure all tires (including
the spare,
if any) are properly inflated.
Buying New Tires
To find out what kind and size of tires you need, look at
the CertificatiodTire label.
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Wheel Alignment and Tire Balance
The wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.
Scheduled wheel alignment and wheel balancing are not
needed. However,
if you notice unusual tire wear or
your vehicle pulling one way or the other, the alignment
may need to be reset.
If you notice your vehicle
vibrating when driving on a smooth road, your wheels
may need to be rebalanced.
Wheel Replacement
Replace any wheel that is bent, cracked, or badly rusted
or corroded. If wheel nuts keep corning loose, the wheel,
wheel bolts and wheel nuts should be replaced. If the
wheel leaks
air, replace it (except some aluminum
wheels, which can sometimes be repaired). See your
dealer if any
of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted the
same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new
GM original equipment
parts. This way, you will be sure to have the
right wheel, wheel bolts and wheel nuts for your vehicle.
~ Using the wrong replacement wheels, wheel bolts
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you
lose control. You could have a collision in which
you or others could be injured. Always use
the correct wheel, wheel bolts and wheel nuts
for replacement.
~
NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, 'bumper
height, vehicle ground clearance and tire or tire
chain clearance to the body and chassis.
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Finish Damage Chemical Paint Spotting
Any
stone chips, fractures or deep scratches in the finish
should be repaired right away. Bare metal will corrode
quickly and may develop into a major repair expense.
Minor chips and scratches can be repaired with touch-up
materials available from your dealer or other service
outlets. 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, ft-ame, floor pan and exhaust
system even though they have colrosion protection.
At least every spring, flush these materials from the
underbody with plain wate.r. Clean any areas where mud
and other debris can collect. Dirt packed in closed areas
of the frame should be loosened before being flushed.
Your dealer or an underbody car washing system can do
this
for you.
Some weather and atmospheric conditions can create a
chemical fallout. Airborne pollutants can fall upon and
attack painted surfaces
on your vehicle. This damage
can take two forms: blotchy, ringlet-shaped discolorations, and small irregular dark spots etched into
the paint surface.
Although
no defect in the paint job causes this, GM will
repair, at no charge to
the owner, the surfaces of new
vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs first.
This applies only to materials manufactured and sold by
General Motors. Bodies, body conversions or equipment
not made or sold by General Motors are not covered.
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STARTER RELAY
[-I
[-I
[T)
I BLOWER
n STOPiHAZ
Name
ECM-B RR DEFOG
IGN-E
FUEL
SOL
GLOW PLUG
Usage
Horn, Underhood Lamps
Auxiliary Fan
Injectors, PCM/VCM
Not Used
Air Conditioning
Not Used
Ignition Switch, EGR, Canister
Purge, EVRV Idle Coast Solenoid,
Heated
02, Fuel Heater
(Diesel Engine), Water Sensor
(Diesel Engine)
HTD ST-RR Not Used
LIGHTING Headlamp and Panel Dimmer
BATT Battery, Fuse Block Busbar
IGN-A Ignition Switch
IGN-B Ignition Switch Switch,
Fog and Courtesy Fuses
ABS Anti-Lock Brake Module
BLOWER High Blower Relay
STOP/HAZ Stoplamps
HEATED SEATS Not Used
6-75
Usage
Fuel Pump, PCM/VCM
Rear Window Defogger
Auxiliary Fan Relay Coi
il, AIC
Compressor Relay, Hot Fuel
Module, Dual Tanks
Fuel Solenoid (Diesel Engine)
Glow Plugs (Diesel Engine)
Name
HORN
AUX FAN
ECM- 1
HTD ST-FR
AIC HTD MIR
ENG-
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Cooling System Capacity (Approximate)
After refill, the level must be rechecked. See “Cooling
System” in the Index.
Engine
“VORTEC” 4300
“VORTEC” 5000
“VORTEC” 5700
“VORTEC” 7400
“VORTEC”
7400 w/3500 HD
VLN
w
M
R
J
J
Quantity
13 quarts (12.3 L)
17.5 quarts (16.6 L)
17.5 quarts (16.6
L)
25 quarts (23.5 L)
28.5 quarts (27
L)
Crankcase Capacity (Approximate)
After refill, the level must be rechecked. Add enough
engine oil
so that the fluid is within the proper operating
range. See “Engine Oil” in the Index.
Engine
“VORTEC” 4300
“VORTEC” 5000
“VORTEC” 5700
“VORTEC” 7400
VIN Quantity with Filter?
w 4.5 quarts (4.3 L)
M 5 quarts (4.8 L)
R 5 quarts (4.8 L)
J 6.6 quarts (6.3 L)
foil filter should be changed at every oil change.
Fuel Tank Capacity (Approximate)
PPe Quantity
Short Bed
26 gallons (98 L)
Long Bed
34 gallons (128
L)
Standard Crew Cab 34 gallons (128 L)
Chassis-Cab Front Tank 2 1 gallons (79 L)
Chassis-Cab Rear Tank
18 gallons (68
L)
3500 HD Models Front Tank
21 gallons (79 L)
3500 HD Models Rear Tank
18 gallons (68
L)
Air Conditioning Refrigerants
Not all air conditioning refrigerants are the same.
If the air conditioning system in your vehicle needs
refrigerant, be sure the proper refrigerant is used. If
you’re not sure, ask your dealer.
See the refrigerant charge label under the
hood for
information regarding refrigerant capacity.
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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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