2004 CHEVROLET ASTRO CARGO VAN trailer

Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important weight
to measure because it affects the total or gross weight of
your vehicle. The Gross Vehicle Weight (GVW) includes
the curb weight of the vehicle, any cargo you may carry in
it, and the people who will be riding in the vehicle. If you
have a lot of options, equipment, passengers or cargo in
your vehicle, it will reduce the tongue weight your vehicle
can carry, which will also reduce the trailer weight your
vehicle can tow. And if you will tow a trailer, you must add
the tongue load to the GVW because your vehicle will be
carrying that weight, too. SeeLoading Your Vehicle on
page 4-29for more information about your vehicle’s
maximum load capacity.The trailer tongue weight (A) should be 10 percent to
15 percent of the total loaded trailer weight, up to a
maximum of 200 lbs (92 kg) with a weight carrying
hitch. The trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight, up to
a maximum of 750 lbs (341 kg) with a weight
distributing hitch.
After you’ve loaded your trailer, weigh the trailer
and then the tongue, separately, to see if the weights
are proper. If they aren’t, you may be able to get
them right simply by moving some items around in
the trailer.
Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the upper
limit for cold tires. You’ll nd these numbers on
the Certication/Tire label at the rear edge of the
driver’s door or seeLoading Your Vehicle on page 4-29.
Then be sure you don’t go over the GVW limit for
your vehicle, including the weight of the trailer tongue.
If you use a weight distributing hitch, make sure
you don’t go over the rear axle limit before you apply
the weight distribution spring bars.
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Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough roads
are a few reasons why you’ll need the right hitch.
Weight-Distributing Hitches and Weight
Carrying Hitches
When using a weight-distributing hitch, the hitch
must be adjusted so that the distance (A) remains the
same both before and after coupling the trailer to the
tow vehicle.If you use a step-bumper hitch, your bumper could be
damaged in sharp turns. Make sure you have ample
room when turning to avoid contact between the trailer
and the bumper.
If you’ll be pulling a trailer that, when loaded, will weigh
more than 2,000 lbs. (900 kg.), be sure to use a
properly mounted, weight-distributing hitch and sway
control of the proper size. This equipment is very
important for proper vehicle loading and good handling
when you’re driving. You should always use a sway
control if your trailer will weigh more than these limits.
You can ask a hitch dealer about sway controls.
Will you have to make any holes in the body of your
vehicle when you install a trailer hitch?
If you’re using the wiring provided with the
factory-installed trailering package, you should not
need to make any holes in the body of your vehicle.
However, if you have an aftermarket hitch installed,
you may need to make holes in the body.
If you do, then be sure to seal the holes later when
you remove the hitch. If you don’t seal them, deadly
carbon monoxide (CO) from your exhaust can get into
your vehicle as well as dirt and water. See “Carbon
Monoxide” underEngine Exhaust on page 2-29. (A) Body to Ground Distance, (B) Front of Vehicle
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Safety Chains
You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the
tongue of the trailer to help prevent the tongue from
contacting the road if it becomes separated from
the hitch. Instructions about safety chains may be
provided by the hitch manufacturer or by the
trailer manufacturer. Follow the manufacturer’s
recommendation for attaching safety chains and
do not attach them to the bumper. Always leave
just enough slack so you can turn with your rig.
Never allow safety chains to drag on the ground.
Trailer Brakes
If your trailer weighs more than 1,000 lbs (450 kg)
loaded, then it needs its own brakes — and they must
be adequate. Be sure to read and follow the instructions
for the trailer brakes so you’ll be able to install, adjust
and maintain them properly.Your trailer brake system can tap into your vehicle’s
hydraulic brake system, except:
Don’t tap into your vehicle’s brake system if the
trailer’s brake system will use more than 0.02 cubic
inch (0.3 cc) of uid from your vehicle’s master
cylinder. If it does, both braking systems won’t work
well. You could even lose your brakes.
Will the trailer parts take 3,000 psi (20 650 kPa) of
pressure? If not, the trailer brake system must not
be used with your vehicle.
If everything checks out this far, then make the
brake uid tap at the port on the master cylinder
that sends uid to the rear brakes. But don’t
use copper tubing for this. If you do, it will bend
and nally break off. Use steel brake tubing.
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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 not see or smell CO. It can cause
unconsciousness or death. SeeEngine
Exhaust on page 2-29. 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
the climate control setting for maximum
air because it only recirculates the air
inside your vehicle. See Climate Control
System 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.
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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.
Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re a good
deal longer, you’ll need to go much farther beyond the
passed vehicle before you can return to your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, just move that hand
to the left. To move the trailer to the right, move your
hand to the right. Always back up slowly and, if possible,
have someone guide you.
Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider
turns than normal. Do this so your trailer won’t strike
soft shoulders, curbs, road signs, trees or other
objects. Avoid jerky or sudden maneuvers. Signal
well in advance.
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Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have extra
wiring (included in the optional trailering package).
The arrows on your instrument panel will ash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will also ash, telling other drivers
you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou
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.
You can tow in DRIVE (D). You may want to shift the
transmission to THIRD (3) or, if necessary, a lower
gear selection if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
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, seeEngine Overheating
on page 5-29.
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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.
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 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 overll), 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.
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Trailer Wiring Harness
If you have the optional trailering package, your vehicle
will have an eight-wire harness, including the center
high-mounted stoplamp battery feed wire. The harness
is stored on the passenger’s side of the vehicle near
the rear wheel well. This harness has a 30 amp battery
feed wire and no connector, and should be wired by
a qualied electrical technician. After choosing an
aftermarket trailer mating connector pair, have the
technician attach one connector to the eight-wire trailer
harness and the other connector to the wiring harness
on the trailer. Be sure the wiring harness on the trailer
is taped or strapped to the trailer’s frame rail and
leave it loose enough so the wiring doesn’t bend or
break, but not so loose that it drags on the ground.
The eight-wire harness must be routed out of your
vehicle between the rear door and the oor, with enough
of the harness left on both sides so that the trailer or
the body won’t pull it. If you do not have the optional
trailering package, your vehicle will still have a trailering
harness. The harness is located near the passenger’s
side rear wheel well. It consists of six wires that may be
used by after-market trailer hitch installers.The technician can use the following color code chart
when connecting the wiring harness to your trailer.Brown: Rear lamps.
Yellow: Left stoplamp and turn signal.
Dark Green: Right stoplamp and turn signal.
White (Heavy Gage): Ground.
Light Green: Back-up lamps.
White (Light Gage): Center High-Mounted Stoplamp.
Blue: Auxiliary circuit (eight-wire harness only).
Orange: Fused auxiliary (eight-wire harness only).
Store the harness in its original place. Wrap the
harness together and tie it neatly so it won’t
be damaged.
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