2003 CHEVROLET EXPRESS CARGO VAN change time

When to Change Engine Oil
If any one of these are true for you, use the short
trip/city maintenance schedule:
·Most trips are less than 5 miles (8 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).
·You frequently tow a trailer or use a carrier on top
of your vehicle.
·The vehicle is used for delivery service, police, taxi
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 ®lter
every 3,000 miles (5 000 km) or 3 months Ð whichever
occurs ®rst.
If none of them is true, use the long trip/highway
maintenance schedule. Change the oil and ®lter every
7,500 miles (12 500 km) or 12 months Ð whichever
occurs ®rst. Driving a vehicle with a fully warmed engine
under highway conditions will cause engine oil to
break down slower.
How to Reset the CHANGE ENGINE
OIL Light
The GM Oil Life System calculates when to change
your engine oil and ®lter based on vehicle use. Anytime
your oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where you change your oil prior to a
CHANGE ENGINE OIL light being turned on, reset the
system.
To reset the CHANGE ENGINE OIL light, do the
following:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal
three times within ®ve seconds.
3. If the CHANGE ENGINE OIL light ¯ashes for ®ve
seconds, the system is reset.
If the system does not reset, try the procedure once
again. If it still does not reset, see your dealer for
service.
See
Change Engine Oil Light on page 3-37.
5-16

Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission ¯uid
level is when the engine oil is changed.
Change both the ¯uid and ®lter 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 90ÉF (32ÉC) or higher.
·In hilly or mountainous terrain.
·When doing frequent trailer towing.
·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 ¯uid and ®lter every 100,000 miles
(166 000 km).
See
Part A: Scheduled Maintenance Services on
page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the 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 ¯uid can damage
your transmission. Too much can mean that some
of the ¯uid could come out and fall on hot engine
part or exhaust system parts, starting a ®re.
Too little ¯uid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmission ¯uid.
Wait at least 30 minutes before checking the
transmission ¯uid level if you have been driving:
·When outside temperatures are above 90ÉF (32ÉC).
·At high speed for quite a while.
·In heavy traffic ± especially in hot weather.
·While pulling a trailer.
To get the right reading, the ¯uid should be at
normal operating temperature, which is 180ÉF to 200ÉF
(82ÉC to 93ÉC).
5-19

A 50/50 mixture of clean, drinkable water and
DEX-COOLžcoolant will:
·Give freezing protection down to-34ÉF (-37ÉC).
·Give boiling protection up to 265ÉF (129ÉC).
·Protect against rust and corrosion.
·Help keep the proper engine temperature.
·Let the warning lights and gages work as
they should.
Notice:When adding coolant, it is important that
you use only DEX-COOLž(silicate-free) coolant.
If coolant other than DEX-COOLžis added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner -- at 30,000 miles
(50,000 km) or 24 months, whichever occurs ®rst.
Damage caused by the use of coolant other
than DEX-COOL
žis not covered by your new vehicle
warranty.
What to Use
Use a mixture of one-halfclean, drinkable waterand
one-half DEX-COOLžcoolant which won't damage
aluminum parts. If you use this coolant mixture,
you don't need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle's coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you wouldn't get the overheat warning.
Your engine could catch ®re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and the proper coolant.
Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost wouldn't be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
Notice:If you use the proper coolant, you don't
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
5-22

Replacing Brake System Parts
The braking system on a 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 Ð for example, when your brake linings
wear down and you need new ones put in Ð 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 Ð 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.
Battery
Your new vehicle comes with a maintenance free
ACDelcožbattery. When it's time for a new battery, get
one that has the replacement number shown on the
original battery's label. We recommend an ACDelco
ž
battery. SeeEngine Compartment Overview on
page 5-12for battery location.
Warning:Battery posts, terminals and related
accessories contain lead and lead compounds,
chemicals known to the State of California to cause
cancer and reproductive harm. Wash hands after
handling.
Vehicle Storage
If you're not going to drive your vehicle for 25 days
or more, remove the black, negative (-) cable from the
battery. This will help keep your battery from
running down.
{CAUTION:
Batteries have acid that can burn you and gas
that can explode. You can be badly hurt if you
aren't careful. See ªJump Startingº next for
tips on working around a battery without
getting hurt.
Contact your dealer to learn how to prepare your
vehicle for longer storage periods.
Also, for your audio system, see
Theft-Deterrent
Feature (Non-RDS Radios) on page 3-73orTheft-Deterrent Feature (RDS Radios) on page 3-73.
5-40

When you install dual wheels, be sure that vent holes in
the inner and outer wheels on each side are lined up.
After the tires have been rotated, adjust the front
and rear in¯ation pressures as shown on the
Certi®cation/Tire label. Make certain that all wheel nuts
are properly tightened. See ªWheel Nut Torqueº
under
Capacities and Speci®cations on page 5-97.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
places where the wheel attaches to the vehicle.
In an emergency, you can use a cloth or a
paper towel to do this; but be sure to use a
scraper or wire brush later, if you need to, to
get all the rust or dirt off. See ªChanging a Flat
Tireº in the Index.
When It Is 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 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.
5-59

6. Remove any rust or dirt
from the wheel bolts,
mounting surfaces
and spare wheel.
{CAUTION:
Rust or dirt on the wheel, or on the parts to
which it is fastened, can make the wheel nuts
become loose after a time. The wheel could
come off and cause an accident. When you
change a wheel, remove any rust or dirt from
the places where the wheel attaches to the
vehicle. In an emergency, you can use a cloth
or a paper towel to do this; but be sure to use
a scraper or wire brush later, if you need to, to
get all the rust or dirt off.
{CAUTION:
Never use oil or grease on studs or nuts. If
you do, the nuts might come loose. Your wheel
could fall off, causing a serious accident.
7. Put the wheel nuts
back on with the
rounded end of the
nuts toward the wheel.
Tighten each wheel
nut by hand until
the wheel is held
against the hub.
8. Lower the vehicle by turning the jack handle
counterclockwise. Lower the jack completely.
5-76

Normal Maintenance Replacement Parts
Replacement part numbers listed in this section are based on the latest information available at the time of printing,
and are subject to change. If a part listed in this manual is not the same as the part used in your vehicle when it was
built, or if you have any questions, please contact your GM dealer.
These speci®cations are for information only. If you have any questions, see the service manual for the chassis or
refer to the body manufacturer's publications.
VIN Code W V T U
Oil Filter* PF47 PF44 PF44 PF44
Engine Air Cleaner /Filter* A1621C A1621C A1621C A1621C
Passenger Compartment Air Filter
Kit**52485513 52485513 52485513 52485513
PCV Valve* CV 769±C CV 2001±C CV 2001±C CV 2001±C
Spark Plugs 41±932 41±974 41±974 41±974
Fuel Filter* 6F6Z6 GF626 GF626 GF626
Wiper Blades** 15153642 15153642 15153642 15153642
Wiper Blade Type ITTA ITTA ITTA ITTA
Wiper Blade Length22 inches
(56.0 cm)22 inches
(56.0 cm)22 inches
(56.0 cm)22 inches
(56.0 cm)
* ACDelco
žpart number
** GM part number
5-100

Inspection (cont.)
Steering and Suspension..............................6-16
Throttle System...........................................6-17
Transfer Case and Front Axle
(All-Wheel Drive)......................................6-17
Instrument Panel Brightness Control..................3-16
Instrument Panel.............................................3-24
Cluster.......................................................3-24
Overview..................................................... 3-4
Interior Lamps................................................3-16
J
Jump Starting.................................................5-41
K
Key Lock Cylinders Service..............................6-13
Keyless Entry System....................................... 2-3
Keys............................................................... 2-2
L
Lamps On Reminder.......................................3-14
Lamps...........................................................3-13
Exterior......................................................3-13
Interior.......................................................3-16Lap Belt........................................................1-26
Lap-Shoulder Belt...........................................1-16
LATCH System...............................................1-51
Child Restraints...........................................1-51
Securing a Child Restraint Designed for the
LATCH System........................................1-53
Leaving Your Vehicle With the Engine
Running.....................................................2-28
Leaving Your Vehicle.......................................2-10
Light.............................................................3-28
Air Bag Off .................................................3-28
Air Bag Readiness.......................................3-27
Anti-Lock Brake System Warning...................3-32
Brake System Warning.................................3-31
Change Engine Oil......................................3-37
Charging System.........................................3-29
Check Gages Warning.................................3-38
Cruise Control.............................................3-38
Daytime Running Lamps Indicator..................3-38
Low Coolant Warning...................................3-33
Malfunction Indicator....................................3-33
Safety Belt Reminder...................................3-26
Security.....................................................3-37
Tow/Haul Mode...........................................3-38
Loading Your Vehicle.......................................4-29
Locking Rear Axle............................................ 4-8
Lockout Protection..........................................2-10
8