2003 GMC SAFARI brake

Payload
The Payload Capacity is shown on the Certication/Tire
label. This is the maximum load capacity that your vehicle
can carry. Be sure to include the weight of the people
inside as part of your load. If you added any accessories
or equipment after your vehicle left the factory, remember
to subtract the weight of these things from the payload.
Your dealer can help you with this.
Trailering Package
There is a load rating which includes the weight of the
vehicle and the trailer it tows. This rating is called
the Gross Combination Weight Rating (GCWR).
When you weigh your trailer, be sure to include the
weight of everything you put in it. And, remember
togure the weight of the people inside the vehicle as
part of your load.
Add-On Equipment
When you carry removable items, you may need to put
a limit on how many people you carry inside your
vehicle. Be sure to weigh your vehicle before you buy
and install the new equipment.
Towing a Trailer
{CAUTION:
If you don’t use the correct equipment and
drive properly, you can lose control when you
pull a trailer. For example, if the trailer is too
heavy, the brakes may not work well -- or even
at all. You and your passengers could be
seriously injured. Pull a trailer only if you have
followed all the steps in this section. Ask your
dealer for advice and information about towing
a trailer with your vehicle.
Notice:Pulling a trailer improperly can damage
your vehicle and result in costly repairs not covered
by your warranty. To pull a trailer correctly, follow
the advice in this part, and see your dealer for
important information about towing a trailer with
your vehicle. Additional rear axle maintenance
is required for a vehicle used to tow a trailer. See
“Scheduled Maintenance Services”in the Index.
To identify what the vehicle trailering capacity is for your
vehicle, you should read the information in“Weight of
the Trailer”that appears later in this section.
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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) ofuid 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
brakeuid tap at the port on the master cylinder that
sendsuid 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’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.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.
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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.
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 willash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will alsoash, telling other drivers
you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel willash 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).
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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 5-28.
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.
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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 transmissionuid (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 yound 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
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 betweenthe rear door and theoor, 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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Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of Your
Vehicle......................................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Specifications....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-6
Filling a Portable Fuel Container.......................5-9
Checking Things Under the Hood.....................5-9
Hood Release..............................................5-10
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-13
Engine Cover...............................................5-17
Engine Air Cleaner/Filter................................5-21
Automatic Transmission Fluid.........................5-22
Engine Coolant.............................................5-25
Radiator Pressure Cap..................................5-27
Engine Overheating.......................................5-28
Cooling System............................................5-30
Engine Fan Noise.........................................5-36
Power Steering Fluid.....................................5-36
Windshield Washer Fluid
................................5-37Brakes........................................................5-39
Battery........................................................5-42
Jump Starting...............................................5-43
All-Wheel Drive..............................................5-48
Rear Axle.......................................................5-49
Front Axle......................................................5-49
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps..................................................5-51
Front Turn Signal Lamps...............................5-54
Taillamps.....................................................5-54
Replacement Bulbs.......................................5-56
Windshield Wiper Blade Replacement..............5-56
Tires..............................................................5-57
Inflation -- Tire Pressure................................5-58
Tire Inspection and Rotation...........................5-58
When It Is Time for New Tires.......................5-60
Buying New Tires.........................................5-60
Uniform Tire Quality Grading..........................5-61
Wheel Alignment and Tire Balance..................5-63
Wheel Replacement......................................5-63
Tire Chains..................................................5-64
If a Tire Goes Flat........................................5-64
Changing a Flat Tire.....................................5-65
Compact Spare Tire......................................5-75
Section 5 Service and Appearance Care
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Filling a Portable Fuel Container
{CAUTION:
Neverll a portable fuel container while it is in
your vehicle. Static electricity discharge from
the container can ignite the gasoline vapor.
You can be badly burned and your vehicle
damaged if this occurs. To help avoid injury to
you and others:
Dispense gasoline only into approved
containers.
Do notll a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed or
on any surface other than the ground.
Bring thell nozzle in contact with the
inside of thell opening before operating
the nozzle. Contact should be maintained
until thelling is complete.
Don’t smoke while pumping gasoline.
Checking Things Under
the Hood
{CAUTION:
Things that burn can get on hot engine parts
and start are. These include liquids like fuel,
oil, coolant, brakeuid, windshield washer and
otheruids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
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