2003 GMC SONOMA towing

If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the
oor. It may take longer to stop. If the light is still on,
have the vehicle towed for service. SeeTowing
Your Vehicle on page 4-42.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you’ve pulled off the road and stopped
carefully, have the vehicle towed for service.
Anti-Lock Brake System Warning
Light
With the anti-lock brake
system, this light will
come on when you start
your engine and may
stay on for several
seconds. That’s normal.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. If the regular brake
system warning light isn’t on, you still have brakes, but
you don’t have anti-lock brakes. If the regular brake
system warning light is also on, you don’t have anti-lock
brakes and there’s a problem with your regular
brakes. SeeBrake System Warning Light on page 3-27.
The anti-lock brake system warning light should come
on briey when you turn the ignition key to RUN. If
the light doesn’t come on then, have itxed so it will be
ready to warn you if there is a problem.
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The SERVICE ENGINE SOON or CHECK ENGINE light
comes on to indicate that there is a problem and
service is required. Malfunctions often will be indicated
by the system before any problem is apparent. This
may prevent more serious damage to your vehicle. This
system is also designed to assist your service
technician in correctly diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, your emission controls
may not work as well, your fuel economy may not
be as good and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake or fuel system of your
vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and may cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.
This light should come on, as a check to show you it is
working, when the ignition is on and the engine is not
running. If the light doesn’t come on, have it repaired.This light will also come on during a malfunction in one of
two ways:
Light Flashing—Amisre condition has been
detected. A misre increases vehicle emissions and
may damage the emission control system on your
vehicle. Diagnosis and service may be required.
Light On Steady—An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
If the Light Is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed.
Avoiding hard accelerations.
Avoiding steep uphill grades.
If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stopsashing and remains on steady, see
“If the Light Is On Steady”following.
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Your Driving, the Road, and Your Vehicle..........4-2
Defensive Driving...........................................4-2
Drunken Driving.............................................4-2
Control of a Vehicle........................................4-5
Braking.........................................................4-5
Locking Rear Axle..........................................4-7
Steering........................................................4-8
Off-Road Recovery.......................................4-10
Passing.......................................................4-10
Loss of Control.............................................4-12
Off-Road Driving with Your Four-Wheel-Drive
Vehicle....................................................4-13
Driving at Night............................................4-27
Driving in Rain and on Wet Roads
..................4-28
City Driving
..................................................4-31Freeway Driving...........................................4-32
Before Leaving on a Long Trip.......................4-33
Highway Hypnosis........................................4-34
Hill and Mountain Roads................................4-34
Winter Driving..............................................4-36
If You Are Stuck: In Sand, Mud,
Ice or Snow..............................................4-40
Towing..........................................................4-42
Towing Your Vehicle.....................................4-42
Recreational Vehicle Towing...........................4-42
Loading Your Vehicle....................................4-46
Truck-Camper Loading Information..................4-48
Trailer Recommendations...............................4-50
Pickup Conversion to Chassis Cab..................4-50
Towing a Trailer...........................................4-51
Section 4 Driving Your Vehicle
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If You Are Stuck: In Sand, Mud,
Ice or Snow
In order to free your vehicle when it is stuck, you will need
to spin the wheels, but you don’t want to spin your wheels
too fast. The method known as“rocking”can help you get
out when you’re stuck, but you must use caution.
{CAUTION:
If you let your tires spin at high speed, they
can explode, and you or others could be
injured. And, the transmission or other parts of
the vehicle can overheat. That could cause an
engine compartment fire or other damage.
When you’re stuck, spin the wheels as little as
possible. Don’t spin the wheels above 35 mph
(55 km/h) as shown on the speedometer.
Notice:Spinning your wheels can destroy parts of
your vehicle as well as the tires. If you spin the
wheels too fast while shifting your transmission
back and forth, you can destroy your transmission.
For information about using tire chains on your
vehicle, seeTire Chains on page 5-66.
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. If you have a
four-wheel-drive vehicle, shift into 4HI. Then shift
back and forth between REVERSE (R) and a forward
gear (or with a manual transmission, between FIRST (1)
or SECOND (2) and REVERSE (R)), spinning the
wheels as little as possible. Release the accelerator
pedal while you shift, and press lightly on the accelerator
pedal when the transmission is in gear. By slowly
spinning your wheels in the forward and reverse
directions, you will cause a rocking motion that may free
your vehicle. If that doesn’t get you out after a few
tries, you may need to be towed out. Or, you can use
your recovery hooks if your vehicle has them. If you do
need to be towed out, seeTowing Your Vehicle on
page 4-42.
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Towing
Towing Your Vehicle
Consult your dealer or a professional towing service if
you need to have your disabled vehicle towed. See
Roadside Assistance Program on page 7-5.
If you want to tow your vehicle behind another vehicle
for recreational purposes (such as behind a motorhome),
see“Recreational Vehicle Towing”following.
Recreational Vehicle Towing
Recreational vehicle towing means towing your vehicle
behind another vehicle–such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as“dinghy towing”(towing your
vehicle with all four wheels on the ground) and
“dolly towing”(towing your vehicle with two wheels on
the ground and two wheels up on a device known
as a“dolly”).With the proper preparation and equipment, many
vehicles can be towed in these ways. SeeDinghy
TowingandDolly Towing,following.
Here are some important things to consider before you
do recreational vehicle towing:
What’s the towing capacity of the towing vehicle?
Be sure you read the tow vehicle manufacturer’s
recommendations.
How far will you tow? Some vehicles have
restrictions on how far and how long they can tow.
Do you have the proper towing equipment?
See your dealer or trailering professional for
additional advice and equipment recommendations.
Is your vehicle ready to be towed? Just as you
would prepare your vehicle for a long trip, you’ll
want to make sure your vehicle is prepared to be
towed. SeeBefore Leaving on a Long Trip on
page 4-33.
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Dinghy Towing
Notice:Towing your vehicle with all four wheels on
the ground will damage drivetrain components.Your two-wheel-drive vehicle should not be towed with
all four wheels on the ground. Your transmission
has no provision for internal lubrication while being
towed. To properly to your vehicle, it should be placed
on a platform trailer with all four wheels off the
ground. Towing with all four wheels on the ground
should be avoided.
In rare cases when it’s unavoidable and your vehicle
must be towed with all four wheels on the ground,
the propeller shaft to axle yoke orientation should be
marked and the propeller shaft removed following
the applicable service manual removal/installation
procedure. SeeService Publications Ordering
Information on page 7-9.
Dust or dirt can enter the back of the transmission
through the opening created by removing the propeller
shaft if proper protection is not provided. Also, check
the transmissionuid level before driving the vehicle. Two-Wheel Drive Vehicles Only
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When towing your vehicle, turn the ignition to OFF.
To prevent your battery from draining while towing,
remove the RDO BATT and CLSTR fuses from
the instrument panel fuse block. Be sure to replace the
fuse when you reach your destination. SeeFuses
and Circuit Breakers on page 5-89. Be sure to use the
proper towing equipment designed for recreational
vehicle towing. Follow the instructions for the towing
equipment.
{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle to
roll even if the transmission is in Park (P) for
an automatic transmission, or if your vehicle is
in gear, for a manual transmission. You or
others could be injured. Make sure the parking
brake isfirmly set before you shift the transfer
case to NEUTRAL.
If your vehicle has four-wheel-drive it cannot be dinghy
towed. A four-wheel-drive vehicle must be towed by
atbed.
Dolly Towing
Notice:Towing your vehicle with all four wheels on
the ground will damage drivetrain components.
Your two-wheel-drive vehicle should not be towed with
two wheels on the ground. Your transmission has no
provision for internal lubrication while being towed.
To properly tow your vehicle, it should be placed on a
platform trailer with all four wheels off the ground. Towing
with all four wheels on the ground should be avoided.Two-Wheel-Drive Vehicles Only
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In rare cases when it’s unavoidable and your vehicle
must be towed with two wheels on the ground, the
propeller shaft to axle yoke orientation should be marked
and the propeller shaft removed following the applicable
service manual removal/installation procedure. See
Service Publications Ordering Information on page 7-9.
Dust or dirt can enter the back of the transmission
through the opening created by removing the propeller
shaft if proper protection is not provided. Also, check
the transmissionuid level before driving the vehicle.
Use the following steps to dolly tow your vehicle:
1. Put the front wheels on a dolly.
2. Put the vehicle in PARK (P).
3. Set the parking brake and then remove the key.
4. Disconnect the propshaft as described above.
5. Clamp the steering wheel in a straight-ahead
position with a clamping device designed for towing.
6. Release the parking brake.Be sure to use the proper towing equipment designed
for recreational vehicle towing. Follow the instructions for
the towing equipment.
{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle to
roll even if the transmission is in Park (P) for
an automatic transmission, or if your vehicle is
in gear, for a manual transmission. You or
others could be injured. Make sure the parking
brake isfirmly set before you shift the transfer
case to NEUTRAL.
If your vehicle has four-wheel-drive it cannot be dolly
towed. A four-wheel-drive vehicle must be towed
byatbed.
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