1998 CHEVROLET EXPRESS air condition

Downloaded from www.Manualslib.com manuals search engine If your vehicle has a 7.4 liter engine and air
conditioning, your vehicle will have a auxiliary
engine fan in addition to
the belt driven fan.
Before closing the hood, be sure all the filler caps
are on properly.
Then lift the hood to relieve pressure
on the hood prop.
Remove the hood prop from the slot in the hood and
return the prop to its retainer. Then just let the hood
down and close it firmly.
Noise Control System
The following information relates to compliance with
Federal noise emission standards for vehicles with a
Gross Vehicle Weight Rating
(GVWR) of more than
10,000 lbs. (4 536 kg). The Maintenance Schedule
provides information on maintaining the noise control
system
to minimize degradation of the noise emission
control system during the life
of your vehicle. The
noise control system warranty is given in your
Warranty booklet.
These standards apply only
to vehicles sold in the
United States.
Tampering With Noise Control
System Prohibited
Federal law prohibits the following acts or the causing
thereof
1.
2.
The removal or rendering inoperative by any person,
other than for purposes
of maintenance, repair or
replacement, of any device or element of design
incorporated into any new vehicle for the purpose
of noise control, prior
to its sale or delivery to the
ultimate purchaser or while it is in use; or
The use of the vehicle after such device or element
of design has been removed or rendered inoperative
by any person.
Among
those acts presumed to constitute tampering are
the acts listed below.
Insulation:
Removal of the noise shields or underhood insulation.
Engine:
Removal or rendering engine speed governor (if
equipped) inoperative
so as to allow engine speed to
exceed manufacturer specifications.

Downloaded from www.Manualslib.com manuals search engine If none of them is true, use the long trip/highway
maintenance schedule. Change the oil and filter every
7,500 miles (12 500 km) or 12 months -- whichever
occurs first. Driving a vehicle with a fully warmed
engine under highway conditions causes engine oil
to break down slower.
What to Do with Used Oil
Did you know that used engine oil contains certain
elements that may be unhealthy for your
skin and could
even cause cancer? Don't let used oil stay
on your skin
for very long. Clean your skin and nails with soap and
water, or a good hand cleaner. Wash or properly throw
away clothing or rags containing used engine oil. (See
the manufacturer's warnings about the use and disposal
of oil products.)
Used oil can be a real threat to the environment. If you
change your own oil, be sure to drain all free-flowing
oil from the filter before disposal. Don't ever dispose of
oil by putting it in the trash, pouring it
on the ground,
into sewers,
or into streams or bodies of water. Instead,
recycle
it by taking it to a place that collects used oil. If
you have
a problem properly disposing of your used oil,
ask your dealer, a service station or a local recycling
center for help.
6-
Air Cleaner (Gasoline Engines)
To remove the air cleaner filter:
1. Loosen the screw bolt to air induct hose.
2. Remove the three bolts holding the air cleaner
housing in place.
3. Remove the full air housing.
4. Unsnap the three clips.
Then tilt the top cover up and back to expose the
filter element.

Downloaded from www.Manualslib.com manuals search engine 5. Install a new filter element with the folds in the
down position.
Reverse Steps 1 through
4 to replace the air cleaner.
See “Normal Replacement Parts” for the proper filter
to use.
Refer to the Maintenance Schedule
to determine when to
replace the air filter and crankcase ventilation filter.
See “Scheduled Maintenance Services” in the Index.
I /!1 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: I
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.
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
regularly reaches
90” F (32” C) or higher.
In hilly or mountainous terrain.
0 When doing frequent trailer towing.
6-17

Downloaded from www.Manualslib.com manuals search engine Brake Wear
Your vehicle has front disc brakes and rear drum brakes.
Disc brake pads have built-in wear indicators that
make
a high-pitched warning sound when the brake
pads are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving (except when you
are pushing on the brake
pedal firmly).
r
I
The brake wear warning sound means that soon
your brakes won’t work well. That could lead to
an accident. When you hear the brake wear
warning sound, have your vehicle serviced.
I NOTICE:
Continuing to drive with worn-out brake pads
could result in costly brake repair.
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.
Your rear drum brakes 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.

Downloaded from www.Manualslib.com manuals search engine When It’s Time for New Tires
One way to tell when it’s
time for new tires
is to
check the treadwear
indicators, which will
appear when your tires have
only 1/16 inch
(1.6 mm) or
less
of tread remaining.
Some commercial truck
tires may not have
treadwear indicators.
You need
a new tire if any of the following statements
are true:
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 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.
0 The tread or sidewall is cracked, cut or snagged deep
enough
to show cord or fabric.
6-45
__

Downloaded from www.Manualslib.com manuals search engine Wheel Replacement
Replace any wheel that is bent, cracked, or badly
rusted or corroded. If wheel nuts keep coming 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.
I A CAUTION:
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.
I 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.

Downloaded from www.Manualslib.com manuals search engine 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.
At least every spring, flush these materials from the
underbody with plain water. 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.
Chemical Paint Spotting
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.

Downloaded from www.Manualslib.com manuals search engine Engine Compartment Fuse Relay Center
The fuse block is on the driver’s side of the engine
compartment at the rear.
U
NAME
IGN-B
IGN-A
BATT
LIGHTING
RR BLOWER
ENG-I
NAME
BLOWER ABS
CIRCUITS PROTECTED
Front Blower Motor
Electronic Brake Control Module AIC
SPARE
AUX A
AUX B
RH-HDLP
CIRCUITS PROTECTED
Ignition
Switch
Starter Relay, Ignition Switch
Instrument Panel
Fuse Block
Instrument Panel Fuse Block,
Headlamp Switch
Rear Auxiliary Blower Motor Relays
Heated
02 Sensors, Mass Air Flow
Sensor, EGR Valve Solenoid, Evap
Canister Purge Valve, Crankshaft
Position Sensor, Secondary Air Injection Relay (Diesel), Water in
Fuel Sensor (Diesel), Fuel Heater
(Diesel), Glowplug Relay (Diesel),
Wastegate Solenoid (Diesel)
Air Conditioning Clutch Relay
Spare Fuses
Upfitter Provisions Upfitter Provisions
Right-hand Headlamp (Export only)