1998 CHEVROLET EXPRESS maintenance

Downloaded from www.Manualslib.com manuals search engine As shown in the chart, SAE 5W-30 is best for your
vehicle. However, you can
use SAE 1OW-30 if it's going
to be
0" F (- 18 " C) or above. These numbers on an oil
container show its viscosity, or thickness. Do not use
other viscosity oils, such as
SAE 20W-50.
NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines "Starburst" symbol. Failure to use the
recommended oil can result in engine damage not covered by your warranty.
GM Goodwrench@ oil meets all the requirements for
your vehicle.
If you are in an area where the temperature falls
below -20°F
(-29 "C), consider using either an
SAE 5W-30 synthetic oil or an SAE OW-30 oil. Both
will provide easier cold starting and better protection
for your engine at extremely low temperatures.
Engine Oil Additives
Don't add anything to your oil. Your dealer is ready to
advise if
you think something should be added.
When to Change Engine Oil
If any one of these is true for you, use the short tripkity
maintenance schedule:
Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
Most trips include extensive idling (such as frequent
driving
in stop-and-go traffic).
Most trips are through dusty areas.
You frequently tow a trailer or use a carrier on top of
The vehicle is used for delivery service, police, taxi
your
vehicle.
or other commercial application.
Driving under these conditions causes engine oil
to
break down sooner. If any one of these is true for your
vehicle,
then you need to change your oil and filter
every
3,000 miles (5 000 km) or 3 months -- whichever
occurs first.

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 Uses such as found in taxi, police or delivery service.
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:
0 When outside temperatures are above 90°F (32°C).
0 At high speed for quite a while.
In heavy traffic -- especially in hot weather.
0 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.
Checking Transmission Fluid Hot
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above
50°F
(10°C). If it’s colder than 50°F (lO”C), drive the
vehicle in
in DRIVE (D) until the engine temperature
gage moves and then remains steady for 10 minutes.
Then follow the hot check procedures.

Downloaded from www.Manualslib.com manuals search engine 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.
How to Add 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 It (0.5 L). Don’t overfill.
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.”
0 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.

Downloaded from www.Manualslib.com manuals search engine Rear Axle What to Use
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. 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
(240
000 kmg 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 with
engine overheating, see “Engine Overheating” in the
Index.
A 50/50 mixture of water and DEX-COOL@
coolant will:
0 Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265 “F (1 29” C).
Protect against rust and corrosion.
0 Help keep the proper engine temperature.
0 Let the warning lights and gages work as
they should.

Downloaded from www.Manualslib.com manuals search engine 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.
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.
Checking Brake Fluid
You can check the brake fluid without taking off the cap.
Just look at the brake fluid reservoir. The fluid level
should be above
MIN. If it isn’t, have your brake system
checked to
see if there is a leak.
6-28

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.