1996 CHEVROLET ASTRO Owners Manual

Maximum trailer weight is calculated assuming the
driver and one passenger are in the tow vehicle and it
has all the required trailering equipment. The weight of
additional optional equipment, passengers and cargo in
the tow vehicle must be subtracted from the maximum
trailer weight.
You
can ask your dealer for our trailering information or
advice, or
you can write us at the address listed in your
Warranty and Owner Assistance Information Booklet.
In Canada, write to:
General Motors
of Canada Limited
Customer Assistance Center
1908 Colonel Sam Drive
Oshawa, Ontario LlH
8P7
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. 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. See “Loading
Your Vehicle” in the Index for more information about
your vehicle’s maximum load capacity.
A B
If you’re using a weight-carrying hitch, the trailer
tongue (A) should weigh 10 percent of the total loaded
trailer weight (B). If you’re using a weight-distributing
hitch,
the trailer tongue (A) should weigh 12 percent of
the total loaded trailer weight (B).
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.
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Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inflated to the limit for
cold tires. You’ll find these numbers
on the Certification
label at the rear edge
of the driver’s door or see “Tire
Loading” in the Index. Then be sure
you don’t go over
the
GVW limit for your vehicle, including the weight of
the trailer tongue.
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. Here are
some rules to follow:
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.
Will you have to make any holes in the body of your
vehicle
when you install a trailer hitch? 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 (see “Carbon Monoxide”
in the Index). Dirt
and water can, too.
Safety Chains
You should always attach chains between your vehicle
and your trailer. Cross the safety chains under the tongue
of the trailer so that the tongue will not drop to 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.
And, never allow safety chains to drag on the ground.
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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:
a
a
a
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 fluid 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
fluid tap at the port
on the master cylinder that sends ’
fluid to the rear brakes. But don’t use copper tubing
for this. If
you do, it will bend and finally break off.
Use steel brake tubing.
Driving with a Trailer
A 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 “Engine Exhaust” 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 “Comfort
Controls” in the Index.)
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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.
lowing Distance
>ray 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.
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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.
Tbrn Signals When Towing a Trailer
When you tow a trailer, your vehicle has to have extra
wiring and a heavy-duty turn signal flasher (included
in
the optional trailering package).
The green arrows on your instrument panel will flash
whenever you signal a turn or lane change. Properly
hooked up, the trailer lamps will also flash, telling other
drivers you’re about to turn, change lanes or stop. When
towing
a trailer, the green arrows on your
instrument panel will flash 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 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.
On a long uphill grade, shift down and reduce your
speed to around
45 mph (70 km/h) to reduce the
possibility
of engine and transmission overheating.
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 “Engine Overheating” in
the Index.
4-35

Parking on Hills
Youereally 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. Turn your wheels into the curb
when facing downhill and away from the curb when
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 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
0 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 fluid (don’t
overfill), engine
oil, axle lubricant, belt, cooling system
and brake adjustment. 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.
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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 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
qualified 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 floor, 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.
0 BROWN: Rear lamps.
YELLOW Left stoplamp and turn signal.
0 DARK GREEN: Right stoplamp and turn signal.
WHITE (Heavy Gage): Ground.
LIGHT GREEN: Back-up lamps.
0 WHITE (Light Gage): Center High-Mounted
0 BLUE: Auxiliary circuit (eight-wire harness only).
0 ORANGE: Fused auxiliary (eight-wire harness only).
xore the harness in its original place. Wrap the harness
together and
tie it neatly so it won’t be damaged.
Stoplamp.
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NOTES
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