2003 CHEVROLET EXPRESS CARGO VAN brake

Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here's
how to do it:
1. Apply your regular brakes, but don't shift into
PARK (P) yet. Then turn your wheels into the curb
if facing downhill or into traffic if facing uphill.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake and then shift to PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
·start your engine,
·shift into a gear, and
·release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you're
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission ¯uid (don't over®ll),
engine oil, axle lubricant, belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you ®nd them quickly. If
you're trailering, it's a good idea to review these sections
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
4-43

Trailer Wiring Harness
The optional heavy-duty trailer wiring package includes
a seven-wire harness assembly at the rear of the
vehicle and a four-wire harness assembly under the left
hand side of the instrument panel. The seven-wire
harness assembly is taped together and located in a
frame pocket at the driver side rear left corner of
the frame. The seven-wire harness includes a
30-amp feed wire. Both harnesses come without
connectors and should be wired by a quali®ed electrical
technician. The technician can use the following
color code chart when connecting the wiring harness to
your trailer and trailer brake controller.Seven-Wire Harness·Light Green: Back-up lamps
·Brown: Parking lamps
·Yellow: Left stoplamp and turn signal
·Dark Green: Right stoplamp and turn signal
·Dark Blue: Use for electric trailer brakes
·Orange: Trailer accessory
·White (heavy gage): Ground wire
Four-Wire Harness (Trailer Brake Controller)
·Black: Ground
·Red/White Stripe: Fused Battery
·Dark Blue: Trailer Brake Feed
·Light Blue: Fused Stop/CHMSL
4-44

Maintenance Schedule......................................6-2
Introduction...................................................6-2
Your Vehicle and the Environment....................6-2
Maintenance Requirements..............................6-2
How This Section is Organized.........................6-3
Part A: Scheduled Maintenance Services...........6-4
Using Your Maintenance Schedule....................6-4
Scheduled Maintenance...................................6-5
Part B: Owner Checks and Services................6-11
At the First 100, 1,000 and 6,000 Miles
(160, 1 600 and 10 000km)........................6-11
At Each Fuel Fill..........................................6-11
At Least Once a Month.................................6-11
At Least Twice a Year...................................6-12At Least Once a Year...................................6-13
Part C: Periodic MaintenanceInspections.........6-16
Steering and Suspension Inspection................6-16
Exhaust System Inspection............................6-16
Fuel System Inspection..................................6-16
Engine Cooling System Inspection...................6-16
Throttle System Inspection.............................6-17
Rear Axle Service.........................................6-17
Transfer Case and Front Axle
(All-Wheel Drive) Inspection........................6-17
Brake System Inspection................................6-17
Part D: Recommended Fluids and
Lubricants................................................6-18
Part E: Maintenance Record...........................6-20
Section 6 Maintenance Schedule
6-1

Scheduled Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of
this vehicle. The services shown at 150,000 miles
(240 000 km) should be repeated at the same interval
after 150,000 miles (240 000 km) for the life of this
vehicle.
See
Part B: Owner Checks and Services on page 6-11andPart C: Periodic MaintenanceInspections on
page 6-16.
Footnotes
²The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle's useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
+A good time to check your brakes is during tire
rotation. See Brake System Inspection on page 6-17.
Engine Oil and Chassis Lubrication
Scheduled Maintenance
Change engine oil and ®lter as indicated by the GM
Oil Life System (or every 12 months, whichever
occurs ®rst.) Reset the system.
Your vehicle has a computer system that lets you know
when to change the engine oil and ®lter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system to work
properly, you must reset the system every time the oil is
changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENGINE OIL message will
come on. Change your oil as soon as possible within
the next two times you stop for fuel. It is possible that, if
you are driving under the best conditions, the oil life
system may not indicate that an oil change is necessary
for over a year. However, your engine oil and ®lter
must be changed at least once a year and at this time
the system must be reset. Your dealer has GM-trained
service people who will perform this work using
genuine GM parts and reset the system.
6-5

30,000 Miles (50 000 km)
qInspect engine air cleaner ®lter change indicator. If
necessary, replace the ®lter. If vehicle is driven in
dusty/dirty conditions, inspect ®lter change indicator
at every engine oil change. See
Engine Air
Cleaner/Filter on page 5-17for more information.An Emission Control Service. (See footnote ².)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle
seals for leaking.
qClean and repack the front wheel bearings
(or at each brake relining, whichever occurs ®rst).
qRotate tires. See
Tire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
qReplace fuel ®lter.An Emission Control Service.
(See footnote ².)
qVehicles With GVWR Above 10,000 lbs. Only:
Inspect shields for damage or looseness. Adjust or
replace as required.
This is a Noise Emission Control
Service. Applicable only to vehicles sold in the
United States.
37,500 Miles (62 500 km)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle
seals for leaking.
qRotate tires. See
Tire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
45,000 Miles (75 000 km)
qInspect engine air cleaner ®lter change indicator. If
necessary, replace the ®lter. If vehicle is driven in
dusty/dirty conditions, inspect ®lter change indicator
at every engine oil change. See
Engine Air
Cleaner/Filter on page 5-17for more information.An Emission Control Service. (See footnote ².)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle
seals for leaking.
qVehicles With GVWR Above 10,000 lbs. Only:
Inspect shields for damage or looseness. Adjust or
replace as required.
This is a Noise Emission Control
Service. Applicable only to vehicles sold in the
United States.
qRotate tires. SeeTire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
6-7

50,000 Miles (83 000 km)
qChange automatic transmission ¯uid and ®lter if the
vehicle's GVWR is over 8,600 lbs or if the vehicle is
mainly driven under one or more of these conditions:
þ In heavy city traffic where the outside
temperature regularly reaches 90ÉF (32ÉC) or
higher.
þ In hilly or mountainous terrain.
þ When doing frequent trailer towing.
þ Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change the ¯uid and ®lter at 100,000 miles
(166 000 km).
52,500 Miles (87 500 km)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle
seals for leaking.
qRotate tires. See
Tire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
60,000 Miles (100 000 km)
qInspect engine air cleaner ®lter change indicator. If
necessary, replace the ®lter. If vehicle is driven in
dusty/dirty conditions, inspect ®lter change indicator
at every engine oil change. See
Engine Air
Cleaner/Filter on page 5-17for more information.An Emission Control Service. (See footnote ².)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle
seals for leaking.
qClean and repack the front wheel bearings
(or at each brake relining, whichever occurs ®rst).
qRotate tires. See
Tire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
qReplace fuel ®lter.An Emission Control Service.
(See footnote ².)
qVehicles With GVWR Above 10,000 lbs. Only:
Inspect shields for damage or looseness. Adjust or
replace as required.
This is a Noise Emission Control
Service. Applicable only to vehicles sold in the
United States.
qInspect Evaporative Control System. Check all fuel
and vapor lines and hoses for proper hook-up,
routing and condition. Check that the purge valve
works properly, if equipped. Replace as needed.
An Emission Control Service. (See footnote ².)
6-8

67,500 Miles (112 500 km)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle
seals for leaking.
qRotate tires. See
Tire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
75,000 Miles (125 000 km)
qInspect engine air cleaner ®lter change indicator. If
necessary, replace the ®lter. If vehicle is driven in
dusty/dirty conditions, inspect ®lter change indicator
at every engine oil change. See
Engine Air
Cleaner/Filter on page 5-17for more information.An Emission Control Service. (See footnote ².)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle
seals for leaking.
qVehicles With GVWR Above 10,000 lbs. Only:
Inspect shields for damage or looseness. Adjust or
replace as required.
This is a Noise Emission Control
Service. Applicable only to vehicles sold in the
United States.
qRotate tires. SeeTire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
82,500 Miles (137 500 km)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle
seals for leaking.
qRotate tires. See
Tire Inspection and Rotation on
page 5-58for proper rotation pattern and additional
information.(See footnote +.)
90,000 Miles (150 000 km)
qInspect engine air cleaner ®lter change indicator. If
necessary, replace the ®lter. If vehicle is driven in
dusty/dirty conditions, inspect ®lter change indicator
at every engine oil change. See
Engine Air
Cleaner/Filter on page 5-17for more information.An Emission Control Service. (See footnote ².)
qCheck rear/front axle ¯uid level and add ¯uid as
needed. Check constant velocity joints and axle
seals for leaking.
qClean and repack the front wheel bearings
(or at each brake relining, whichever occurs ®rst.)
qReplace fuel ®lter.
An Emission Control Service.
(See footnote ².)
qVehicles With GVWR Above 10,000 lbs. Only:
Inspect shields for damage or looseness. Adjust or
replace as required.
This is a Noise Emission Control
Service. Applicable only to vehicles sold in the
United States.
6-9

At Least Once a Year
Key Lock Cylinders Service
Lubricate the key lock cylinders with the lubricant
speci®ed in Part D.
Body Lubrication Service
Lubricate all hood hinges, hood prop rod pivot, fuel ®ller
door, rear compartment hinges, latches, locks, hood
latch assembly, secondary latch, pivots, spring anchor,
release pawl and any moving seat hardware. Part D
tells you what to use. More frequent lubrication may be
required when exposed to a corrosive environment.
Starter Switch Check
{CAUTION:
When you are doing this check, the vehicle
could move suddenly. If it does, you or others
could be injured. Follow the steps below.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. See
Parking Brake on page 2-26if
necessary.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The starter
should work only in PARK (P) or NEUTRAL (N).
If the starter works in any other position, your
vehicle needs service.
6-13