2003 CHEVROLET ASTRO tires

If yours was built with trailering options, as many are,
it’s ready for heavier trailers. But trailering is different
than just driving your vehicle by itself. Trailering means
changes in handling, durability and fuel economy.
Successful, safe trailering takes correct equipment,
and it has to be used properly.
That’s the reason for this part. In it are many time-tested,
important trailering tips and safety rules. Many of these
are important for your safety and that of your passengers.
So please read this section carefully before you pull
a trailer.
If You Do Decide To Pull A Trailer
If you do, here are some important points:
e
e
There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will
be legal, not only where you live
but also where you’ll be driving.
A good source for
this information can be state or provincial police.
Consider using
a sway control if your trailer will
weigh 2,000 Ibs
(900 kg) or less. You should
always use a sway control
if your trailer will weigh
more than 2,000
Ibs (900 kg). You can ask a
hitch dealer about sway controls.
e
e
e
Don’t tow a trailer at all during the first 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during the first
500 miles (800 km) that you
tow a trailer, don’t drive over
50 mph (80 km/h)
and don’t make starts at full throttle. This helps your
engine and other parts of your vehicle wear in at
the heavier loads.
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).
Three important considerations have to do with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle’s tires.
4-32

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
on page
4-29 for more information about your vehicle’s
maximum load capacity.
A B
If you’re using a weight-carrying or a weight-distributing
hitch, the trailer tongue weight (A) should be
10 percent
to
15 percent of the total loaded trailer weight (B).
Do not exceed the maximum allowable tongue weight
for your vehicle.
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 inflated to the upper
limit for cold tires.
You’ll find these numbers on
the Certificationflire label at the rear edge of the driver’s
door or see
Loading 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.
4-35

Driving with a Trailer
If you ~ ve 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
the climate control setting for maximum air because
it only recirculates the air inside
your vehicle. See “Climate Controls” 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.
4-37

Section 5 Service and Appearance Care
Service .......................................................... -5-3
Doing Your Own Service Work
......................... 5-3
Adding Equipment to the Outside of
Your Vehicle
.............................................. 5-4
Fuel ................................................................ 5.5
Gasoline Octane ........................................... -5-5
Gasoline Specifications .................................... 5.5
California Fuel ............................................. -56
Additives
....................................................... 5.6
Fuels in Foreign Countries
............................... 5.7
Filling Your Tank
............................................ 5-8
Filling a Portable Fuel Container
..................... 5-10
Checking Things Under the Hood .................... 5-1 1
Hood Release .............................................. 5.11
Engine Compartment Overview
...................... 5.14
Engine Oil
................................................... 5.15
Engine Cover ................. .... ........ 5.20
Engine Air Cleaner/Filter
................. ........ 5.24
Automatic Transmission Fluid
...................... 5.25
Engine Coolant ............................................. 5.28
Radiator Pressure Cap
.................................. 5.30
Engine Overheating
....................................... 5.31
Cooling System
............................................ 5.33
Engine Fan Noise
......................................... 5.39
Power Steering Fluid
..................................... 5.40
Windshield Washer Fluid
................................ 5.41 Brakes
........................................................ 5.42
Battery
........................................................ 5-46
Jump Starting
............................................... 5-47
All-Wheel Drive .............................................. 5-52
Rear Axle ....................................................... 5-53
Front Axle ...................................................... 5-54
Bulb Replacement .......................................... 5-55
Halogen Bulbs .............................. ..... 5-55
Headlamps .................................. ..... 5-55
Front Turn Signal Lamps ............................... 5-59
Replacement Bulbs
....................................... 5-61
Windshield Wiper Blade Replacement .............. 5-62
Tires .............................................................. 5.63
Inflation
- Tire Pressure ................................ 5-64
Tire Inspection and Rotation
........................... 5-64
When It
Is Time for New Tires ....................... 5-66
Buying New Tires
......................................... 5-66
Uniform Tire Quality Grading
.......................... 5-67
Wheel Alignment and Tire Balance
.................. 5-69
Wheel Replacement
...................................... 5-69
Tire Chains
.................................................. 5-70
If a Tire Goes Flat ........................................ 5.70
Changing a Flat Tire ..................................... 5.71
Compact Spare Tire ...................................... 5-82
Taillamps
.................................................... 5-60
5- 1

Brake Wear
Your vehicle has four-wheel disc brakes,
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake
pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving (except when you are pushing on the
brake pedal firmly).
The brake wear warning sound means that soon
your brakes won’t work well. That could lead to
an accident. When
you hear the brake wear
Notice: Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
Properly torqued wheei nuts are necessary to heip
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to
GM torque specifications.
Brake linings should always be replaced as complete
axle sets.
See
Brake System Inspection on page 6-31.
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
5-45

Tires
Your new vehicle comes with high-quality tires made by
a leading tire manufacturer.
If you ever have questions
about your tire warranty
and where to obtain service,
see your GMC Warranty booklet for details.
Poorl! lail -Jned anc. ..nproy-. ly used tires
are dangerous.
Overloading your tires can cause
overheating as a result of too much
friction. You could have an air-out and a
serious accident. See “Loading Your
Vehicle” in the Index.
CAUTION: (Continued)
0 Underinflated tires pose the same danger
as overloaded tires. The resulting accident
could cause serious injury. Check
all tires
frequently to maintain the recommended pressure. Tire pressure should be checked
when your tires are cold.
Overinflated tires are more likely to be
cut, punctured or broken by
a sudden
impact
- such as when you hit a pothole.
Keep tires at the recommended pressure.
Worn, old tires can cause accidents.
If your tread
is badly worn, or if your tires
have been damaged, replace them.
5-63

Inflation - Tire Pressure
The Certificationnire label, which is on the rear edge of
the driver’s door, shows the correct inflation pressures
for your tires when they’re cold. ‘Cold” means your
vehicle has been sitting for at least three hours or driven
no more than
1 mile (1.6 km).
Notice: Don’t let anyone tell you that underinflation
or overinflation is all right.
It’s not. If your tires
don’t have enough air (underinflation), you can get
the following:
Too much flexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy
If your tires have too much air (overinflation),
you can get the following:
Unusual wear
Bad handling
0 Rough ride
Needless damage from road hazards
When to Check
Check your tires once a month or more.
Don’t forget your compact spare tire. It should be at
60 psi (420 kPa).
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell
if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
(1 0 000 to 13 000 km).
Any time you notice unusual wear, rotate your tires
as soon as possible and check wheel alignment.
Also check for damaged tires or wheels. See
When It
Is Time for New Tires on page 5-66 and Wheel
Replacement on page
5-69 for more information.
5-64

Make sure the spare tire is stored securely. Push,
pull, and then try to rotate or turn the tire.
If it moves,
use the ratchevwheel wrench to tighten the cable.
See
Changing a Flat Tire on page 5-71.
The purpose Gf regular rotation is lo achieve more
uniform wear for all tires on the vehicle. The first rotation
is the most important. See “Part
A: Scheduled
Maintenance Services,” in Section
6, for scheduled
rotation intervals. After
the tires have been rotated, adjust the front and rear
inflation pressures as shown on the CertificationA-ire
label. Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and
Specifications
on page 5-99.
When rotating your tires, always use the correct rotation
patterns shown here.
ts to
-
Rust or dirt on a wheel, or on the par
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 “Changing a
Flat Tire” in the Index.
Don’t include the compact spare tire in your tire rotation.
5-65