2003 GMC SAFARI stop start

Tow/Haul Mode
The tow/haul mode is a feature that assists when pulling
a heavy trailer. The purpose of the tow/haul mode is:
to reduce the frequency of shifts when pulling a
heavy trailer.
to provide the same shift feel when pulling a heavy
trailer as when the vehicle is unloaded.
to reduce the need to change throttle position when
pulling a heavy trailer.
This feature is turned on or off by pressing a button on
the column shift lever. When the feature is on, a
light on the instrument panel will illuminate to indicate
that the tow/haul mode has been selected.
SeeTow/Haul Mode Light on page 3-35. The tow/haul
mode is automatically turned off each time the vehicle is
started.
The tow/haul mode is most effective when the vehicle
and trailer combined weight is at least 75% of the Gross
Vehicle Weight Rating (GVWR) and the maximum
trailer weight rating for the vehicle.The tow/haul mode for hauling a heavy trailer is most
useful under the following conditions:
When driving through hilly terrain at speeds below
55 mph (88 km/h).
When driving in low speed or stop and go traffic
below 55 mph (88 km/h).
When driving in parking lots.
Operating in the tow/haul mode when not pulling a
heavy trailer will not cause damage to the vehicle, but
you may experience reduced fuel economy and
undesirable performance from the engine and
transmission. The tow/haul mode should be used only
when pulling a heavy trailer.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to pull
a trailer are all important. And, it can also depend
on any special equipment that you have on your vehicle.
The following chart shows how much your trailer can
weigh, based upon your vehicle model and options.
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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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As in the chart shown previously, SAE 5W-30 is the
only viscosity grade recommended for your vehicle. You
should look for and use only oils which have the API
Starburst symbol and which are also identified as
SAE 5W-30. If you cannotfind such SAE 5W-30 oils,
you can use an SAE 10W-30 oil which has the API
Starburst symbol, if it’s going to be 0°F(−18°C)
or above. Do not use other viscosity grade oils, such as
SAE 10W-40 or SAE 20W-50 under any conditions.
Notice:Use only engine oil with the American
Petroleum Institute Certied For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
GM Goodwrench
®oil meets all the requirements for
your vehicle.
If you are in an area of extreme cold, where the
temperature falls below−20°F(−29°C),itis
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Don’t add anything to your oil. The recommended oils
with the starburst symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil
If any one of these are true for you, use the short
trip/city maintenance schedule:
•Most trips are less than 5 miles (8 km). This is
particularly important when outside temperatures
are below freezing.
•Most trips include extensive idling (such as frequent
driving in stop-and-go traffic).
•You frequently tow a trailer or use a carrier on top
of your vehicle.
•The vehicle is used for delivery service, police, taxi
or other commercial application.
Driving under these conditions causes engine oil to
break down sooner. If any one of these is true for your
vehicle, then you need to change your oil andfilter
every 3,000 miles (5 000 km) or 3 months—whichever
occursfirst.
If none of them is true, use the long trip/highway
maintenance schedule. Change the oil andfilter every
7,500 miles (12 500 km) or 12 months—whichever
occursfirst. Driving a vehicle with a fully warmed engine
under highway conditions will cause engine oil to
break down slower.
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Fuse/Circuit
BreakerUsage
1 Stop/Turn/Hazard Lamps, Center
High Mounted Stop Lamp, Anti-Lock
Brakes
2 Radio Accy, Rear Seat Audio
ControlsFuse/Circuit
BreakerUsage
3 Courtesy Lamps, Glove Box Lamp,
Dome Reading Lamps, Vanity Mirror
Lamps, Courtesy Lamps
4 Daytime Running Lamps Relay,
Instrument Panel Cluster
5 Rear Defogger
6 Cruise Module, Truck Body Control
Module, Instrument Panel Cluster,
Cruise Control Switch,
Electrochromic Mirror
7 Power Outlets, DLC, Subwoofer
Amplifier
8 Crank Circuit Fuse, Park/Neutral
Switch, Starter Enabler Relay
9 License Plate Lamp, Tailamps,
Parking Lamps, Ashtray Lamp,
Panel Lights, Trailer Taillamps, Front
and Rear Sidemarker Lamps, Door
Switch Illumination, Headlamp
Switch Illumination, Rear Seat Audio
Illumination, Truck Body Control
Module
10 Air Bag System
11 Not Used
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Fuse/Circuit
BreakerUsage
Blank Not Used
RH HDLMP Right Headlamp
LH Headlamp Left Headlamp
Blank Not Used
Blank Not Used
DIODE-1 Air Conditioning
Blank Not Used
Blank Not Used
Blank Not Used
LIGHTING Courtesy Fuse, Power Adjust
Mirrors Fuse, Truck Body Control
Battery FuseFuse/Circuit
BreakerUsage
BATT Power Accessory Circuit Breaker,
Stop/Hazard Fuse, Auxiliary Power
Fuse, Cigarette Lighter Fuse, Radio
Battery Fuse
IGN A Starter Relay, Ignition Switch
IGN B Ignition Switch
ABS Electronic Brake
Control Module
Blank Not Used
RAP Radio Accessory, Power Windows
HTD MIR/RR
DEFOGRear Window Defogger,Climate
Control Head
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