2001 CHEVROLET EXPRESS CARGO VAN engine

4-35
Model Engine Axle Ratio Max. Trailer Weight (lbs.) (kg)
G2500 (Passenger) 5.7L 3.73 5,800 (2633)
4.10 7,300 (3314)
6.5L 3.73 8,100 (3677)
4.10 8,100 (3677)
G3500 (Cargo) 5.7L 3.73 6,300 (2860)
4.10 7,800 (3541)
6.5L 3.73 8,400 (3814)
4.10 8,400 (3814)
8.1L 3.42 7,500 (3405)
3.73 9,000 (4086)
4.10 10,000 (4540)
G3500 (Passenger) 5.7L 3.73 5,600 (2542)
4.10 7,100 (3223)
6.5L 3.73 7,800 (3541)
4.10 7,800 (3541)
8.1L 3.42 6,800 (3087)
3.73 8,300 (3768)
4.10 10,000 (4540)

4-39 Driving with a Trailer
CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon monoxide
(CO) could come into your vehicle. You can't
see or smell CO. It can cause unconsciousness
or death. See ªEngine Exhaustº in the Index.
To maximize your safety when towing a trailer:

Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.

Keep the rear
-most windows closed.

If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
MAX A/C because it only recirculates the
air inside your vehicle. See ªComfort
Controlsº in the Index.
Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you'll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the
trailer. And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check the trailer hitch and platform
(and attachments), safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer moving and
then apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as you
would when driving your vehicle without a trailer. This
can help you avoid situations that require heavy braking
and sudden turns.

4-41 Driving On Grades
Reduce speed and shift to a lower gear before you start
down a long or steep downgrade. If you don't shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If you turn your
engine off immediately after towing at high altitude on
steep uphill grades, your vehicle may show signs similar to
engine overheating. To avoid this, let the engine run while
parked (preferably on level ground) with the automatic
transmission in PARK (P) for a few minutes before turning
the engine off. If you do get the overheat warning, see
ªEngine Overheatingº in the Index.
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.

4-42 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 fluid (don't overfill),
engine oil, axle lubricant, belt, cooling system and brake
system. Each of these is covered in this manual, and the
Index will help you find 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.
Trailer Wiring Harness
The optional heavy-duty trailer wiring package is a
seven
-wire harness assembly. The four-wire portion of
the harness assembly is stored under the vehicle, along
the driver's side rear corner of the frame rail. The
three
-wire portion of the harness assembly is stored in a
frame pocket under the rear of the vehicle, on the
driver's side. The heavy
-duty trailer wiring harness has
a 30
-amp feed wire. Both harnesses come without
connectors and should be wired by a qualified electrical
technician. The technician can use the following color
code chart when connecting the wiring harness to
your trailer.Four
-Wire Harness

Light Green: Back
-up lamps

Brown: Parking lamps

Yellow: Left stoplamp and turn signal

Dark Green: Right stoplamp and turn signal
Three
-Wire Harness

Dark Blue: Use for electric trailer brakes
(seven
-wire harness only)

Orange: Trailer accessory (seven
-wire harness only)

White (heavy gage): Ground wire
Securely attach the harness to the trailer, then tape or
strap it to your vehicle's frame rail. Be sure you leave it
loose enough so the wiring doesn't bend or break, but
not so loose that it drags on the ground. Store the
harness in its original place. Wrap the harness together
and tie it neatly so it won't be damaged.

5-
5-1
Section 5 Problems on the Road
Here you'll find what to do about some problems that can occur on the road.
5
-2 Hazard Warning Flashers
5
-3 Other Warning Devices
5
-3 Jump Starting
5
-9 Towing Your Vehicle
5
-9 Engine Overheating (Gasoline Engine)5
-12 Cooling System (Gasoline Engine)
5
-19 Engine Fan Noise
5
-19 If a Tire Goes Flat
5
-20 Changing a Flat Tire
5
-35 If You're Stuck: In Sand, Mud, Ice or Snow

5-4
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
NOTICE:
If the other system isn't a 12-volt system with a
negative ground, both vehicles can be damaged.
If you have a diesel engine vehicle with two batteries
(or more) you should know before you begin that,
especially in cold weather, you may not be able to
get enough power from a single battery in another
vehicle to start your diesel engine.
If your vehicle has more than one battery, use the
battery that is under the hood of the vehicle. This
will reduce the electrical resistance.2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren't touching
each other. If they are, it could cause a ground
connection you don't want. You wouldn't be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brake firmly on both vehicles involved in
the jump start procedure. Put an automatic
transmission in PARK (P) and a manual transmission
in NEUTRAL.
3. Turn off the ignition on both vehicles. Turn off all
lamps that aren't needed, and radios. This will avoid
sparks and help save both batteries, and could save
your radio.

5-6
CAUTION:
Fans or other moving engine parts can injure you
badly. Keep your hands away from moving parts
once the engine is running.
5. Check that the jumper cables don't have loose or
missing insulation. If they do, you could get a shock.
The vehicles could be damaged, too.
Before you connect the cables, here are some
basic things you should know. Positive (+) will
go to positive (+) and negative (
-) will go to a heavy,
unpainted metal engine part or a body metal surface.
Don't connect positive (+) to negative (
-) or you will
get a short that would damage the battery and maybe
other parts, too. And don't connect the negative (
-)
to negative (
-).
6. Connect the red positive (+) cable to the positive (+)
terminal of the vehicle with the dead battery. Or use
a remote positive (+) terminal if the vehicle has one.

5-7
7. Don't let the other end
touch metal. Connect it
to the positive (+)
terminal of the good
battery. Use a remote
positive (+) terminal if
the vehicle has one.
8. Now connect the black
negative (
-) cable to
the good battery's
negative (
-) terminal.
Don't let the other end
touch anything until the
next step.
9. Make your last connection away from the battery, to
the engine block, frame or other heavy, unpainted
metal parts of your vehicle. A ground location has
been provided through a stud attached to the
body surface.