2001 GMC ENVOY trailer

2-48
As you signal a turn or a lane change, if the arrows flash
more quickly than normal, a signal bulb may be burned
out and other drivers won't see your turn signal.
If a bulb is burned out, replace it to help avoid an
accident. If the arrows don't go on at all when you
signal a turn, check the fuse (see ªFuses and Circuit
Breakersº in the Index) and for burned
-out bulbs.
If you have a trailer towing option with added wiring for
the trailer lamps, a different turn signal flasher is used.
With this flasher installed, the signal indicator will flash
even if a turn signal bulb is burned out. Check the front
and rear turn signal lamps regularly to make sure they
are working.
Turn Signal On Chime
If your turn signal is left on for more than 3/4 of a mile
(1.2 km), a chime will sound at each flash of the turn
signal. To turn off the chime, move the turn signal lever
to the off position.
Headlamp High/Low-Beam Changer
To change the headlamps from low beam to high or
high to low, pull the multifunction lever all the way
toward you. Then release it.
When the high beams
are on, this indicator light
on the instrument panel
cluster will also be on.
Flash-to-Pass
This feature lets you use your high-beam headlamps to
signal a driver in front of you that you want to pass. It works
even if your headlamps are in the automatic position.
To use it, pull the turn signal lever toward you, but not
so far that you hear a click.
If your headlamps are in the automatic position or on
low beam, your high
-beam headlamps will turn on.
They'll stay on as long as you hold the lever toward you
and the high
-beam indicator on the instrument panel
cluster will come on. Release the lever to return to
normal operation.
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2-95
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:
Modifications 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 the SERVICE ENGINE SOON
OR CHECK ENGINE light to come on.
Modifications 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
-- A misfire condition has been
detected. A misfire increases vehicle emissions and
may damage the emission control system on your
vehicle. Dealer or qualified service center diagnosis
and service may be required.

Light On Steady
-- An emission control
system malfunction has been detected on your
vehicle. Dealer or qualified service center 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 stops flashing and remains on steady,
see ªIf the Light Is On Steadyº following.
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4-
4-1
Section 4 Your Driving and the Road
Here you'll find information about driving on different kinds of roads and in varying weather conditions. We've also
included many other useful tips on driving.
4
-2 Your Driving, the Road and Your Vehicle
4
-3 Defensive Driving
4
-4 Drunken Driving
4
-7 Control of a Vehicle
4
-7 Braking
4
-10 Steering
4
-12 Off-Road Recovery
4
-13 Passing
4
-14 Loss of Control
4
-15 Off-Road Driving with Your
Four
-Wheel-Drive Vehicle4
-29 Driving at Night
4
-30 Driving in Rain and on Wet Roads
4
-33 City Driving
4
-34 Freeway Driving
4
-35 Before Leaving on a Long Trip
4
-36 Highway Hypnosis
4
-36 Hill and Mountain Roads
4
-38 Winter Driving
4
-41 Recreational Vehicle Towing
4
-43 Loading Your Vehicle
4
-46 Towing a Trailer
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4-42 Two-Wheel Drive Vehicles and Vehicles
with the Electronic Shift Transfer Case
Tw o-wheel-drive vehicles and vehicles with the
Electronic Shift Transfer Case should not be towed
with all four wheels on the ground. These transmissions
have no provisions for internal lubrication while being
towed. To properly tow these vehicles, they 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
has to 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. See ªService and Owner Publicationsº in
the Index.
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 transmission fluid level before driving the vehicle.
Four-Wheel-Drive Vehicles
(Automatic Transfer Case)
Use the following procedure to correctly tow your
vehicle on all four wheels:
1. Firmly set the parking brake.
2. Place the transmission in PARK (P).
3. Securely attach the vehicle being towed to the
tow vehicle.
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4-43
4. With the engine running, shift the transfer case to
NEUTRAL. See ªFour
-Wheel Driveº in the Index
for the proper procedure to select the NEUTRAL
position for your vehicle.
CAUTION:
Shifting the 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 is firmly set
before you shift the transfer case into NEUTRAL.
See ªFour
-Wheel Drive (Automatic Transfer Case)º
in the Index.
5. Release the parking brake only after the vehicle
being towed is firmly attached to the towing vehicle.
6. Turn the ignition to OFF. The OFF position unlocks
the steering column and reduces battery drain.
Unlocking the steering column will allow the proper
movement of the front wheels and tires during towing.
Loading Your Vehicle
The Certification/Tire label is found on the driver's door
edge, above the door latch. The label shows the size of
your original tires and the inflation pressures needed to
obtain the gross weight capacity of your vehicle. This is
called the Gross Vehicle Weight Rating (GVWR). The
GVWR includes the weight of the vehicle, all occupants,
fuel, cargo and trailer tongue weight, if pulling a trailer.
The Certification/Tire label also tells you the maximum
weights for the front and rear axles, called Gross Axle
Weight Rating (GAWR).
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4-46
The compressor should operate for brief periods of time.
If the sound continues for an extended period of time,
your vehicle needs service. To keep your battery from
being drained, you may want to remove the LD LEV
fuse in the engine compartment fuse block until you
can get your vehicle serviced (see ªFuses and Circuit
Breakersº in the Index).
Using heavier suspension components to get added
durability might not change your weight ratings. Ask
your dealer to help you load your vehicle the right way.
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.
NOTICE:
Your warranty doesn't cover parts or components
that fail because of overloading.
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.
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4-47
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 ªScheduled Maintenance Servicesº
in the Index.
To identify what the vehicle trailering capacity is for
your vehicle, you should read the information in
ªWeight of the Trailerº that appears later in
this section.
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.
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4-48 If You Do Decide To Pull A Trailer
If you do, here are some important points:

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 lbs. (900 kg) or less. You should always
use a sway control if your trailer will weigh more
than 2,000 lbs. (900 kg). You can ask a hitch dealer
about sway controls.

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.

If you have an automatic transmission, you can
use THIRD (3) (or, as you need to, a lower gear)
when towing a trailer. Operating your vehicle in
THIRD (3) when towing a trailer will minimize heat
buildup and extend the life of your transmission.
If you have a manual transmission and you are
towing a trailer, it's better not to use FIFTH (5) gear.
Just drive in FOURTH (4) gear (or, as you need to,
a lower gear). See ªTow/Haul Modeº in the Index.
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.
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