2001 GMC YUKON XL DENALI towing

2-71
If the transmission fluid reaches temperatures of
approximately 275
F (135
C) or greater, the message
center will display a TRANS HOT...IDLE ENG warning
message. Pull the vehicle off the roadway when it is safe
to do so. Set the parking brake, place the transmission in
PARK (P) and allow the engine to idle until the
transmission temperature falls below 260
F (127
C).
If the transmission continues to operate above 265
F
(130
C), please contact your nearest dealer or the GM
Roadside Assistance Center.
NOTICE:
If you keep driving your vehicle with the
transmission temperature gage above the normal
operating range, you can damage the
transmission. This could lead to costly repairs
that may not be covered under your warranty.
The following situations can cause the transmission to
operate at higher temperatures:

Towing a trailer

Hot outside air temperatures

Hauling a large or heavy load

Low transmission fluid level

High transmission fluid level

Restricted air flow to the radiator and the auxiliary
transmission oil cooler (if equipped).
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures on
a frequent basis, see ªScheduled Maintenanceº in the
Index for the proper transmission maintenance intervals.

2-73
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.
If the light continues to flash, when it is safe to do so,
stop the vehicle. Find a safe place to park your vehicle.
Turn the key off, wait at least 10 seconds and restart the
engine. If the light remains on steady, see ªIf the Light
Is On Steadyº following. If the light is still flashing,
follow the previous steps, and drive the vehicle to your
dealer or qualified service center for service.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. See ªFilling Your Tankº in the Index. The
diagnostic system can determine if the fuel cap has been
left off or improperly installed. A loose or missing fuel
cap will allow fuel to evaporate into the atmosphere. A
few driving trips with the cap properly installed should
turn the light off.

2-78 Trans Fluid Hot
Your vehicle has a transmission temperature warning
display contained in the message center.
If the transmission fluid
temperature becomes high,
the message center will
display this message.
When the transmission enters the protection mode,
you may notice a change in the transmission shifting
patterns. When the transmission fluid temperature
returns to normal, the display will turn off and the
transmission shifting patterns will return to normal.
NOTICE:
If you keep driving your vehicle with the
transmission TRANS FLUID HOT message
displayed, you can damage the transmission. This
could lead to costly repairs that may not be
covered under your warranty.
The following situations can cause the transmission to
operate at higher temperatures:

Towing a trailer

Hot outside air temperatures

Hauling a large or heavy load

Low transmission fluid level

High transmission fluid level

Restricted air flow to the radiator and the auxiliary
transmission oil cooler (if equipped).
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures on
a frequent basis, see ªScheduled Maintenanceº in the
Index for the proper transmission maintenance intervals.

2-79 Trans Hot...Idle Engine
Your vehicle has a transmission over-temperature
display contained in the message center.
If this warning message is
displayed, pull the vehicle
off the roadway when it is
safe to do so.
Set the parking brake and place the transmission in
PARK (P). Idle the engine until the message center no
longer displays a message. If idling the engine does not
turn the warning message off after 10 to 15 minutes,
contact your nearest dealer or the GM Roadside
Assistance Center. See ªRoadside Assistanceº in
the Index.
NOTICE:
If you keep driving your vehicle with the
transmission TRANS HOT...IDLE ENGINE
message displayed, you can damage the
transmission. This could lead to costly repairs
that may not be covered under your warranty.
The following situations can cause the transmission to
operate at higher temperatures:

Towing a trailer

Hot outside air temperatures

Hauling a heavy load

Low transmission fluid level

High transmission fluid level

Restricted air flow to the radiator and the auxiliary
transmission oil cooler (if equipped).
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures on
a frequent basis, see ªScheduled Maintenanceº in the
Index for the proper transmission maintenance intervals.

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 Defensive Driving
4
-3 Drunken Driving
4
-6 Control of a Vehicle
4
-6 Braking
4
-9 Steering
4
-11 Off-Road Recovery
4
-12 Passing
4
-13 Loss of Control
4
-14 Operating Your All-Wheel-Drive Vehicle
Off Paved Roads
4
-27 Driving at Night4
-29 Driving in Rain and on Wet Roads
4
-32 City Driving
4
-33 Freeway Driving
4
-34 Before Leaving on a Long Trip
4
-35 Highway Hypnosis
4
-35 Hill and Mountain Roads
4
-37 Winter Driving
4
-41 Recereational Vehicle Towing
4
-41 Loading Your Vehicle
4
-43 Towing a Trailer

4-41
Recreational Vehicle Towing
Your vehicle was not designed to be towed with all
four wheels on the ground, nor was it designed to be
towed with only two wheels on the ground. If your
vehicle must be towed, see ªTowing Your Vehicleº in
the Index.
NOTICE:
Towing your vehicle with all four wheels on
the ground will damage drivetrain components.
And, since your vehicle has all
-wheel drive,
towing with only two wheels on the ground will
also damage drivetrain components.
Loading Your Vehicle
The Certification/Tire label is found on the rear edge of
the driver's door or in the Incomplete Vehicle Document
in the cab.
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 GVWR
(Gross Vehicle Weight Rating). The GVWR includes
the weight of the vehicle, all occupants, fuel and cargo.
The Certification/Tire label also tells you the maximum
weights for the front and rear axles, called Gross Axle
Weight Rating (GAWR).

4-43
There's also important loading information for off-road
driving in this manual. See ªLoading Your Vehicle for
Off
-Road Drivingº in the Index.
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.
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.

4-48 Trailer Brakes
If your trailer weighs more than 2,000 lbs. (900 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 the vehicle's
hydraulic brake system only if:

The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.

The trailer's brake system will use less than
0.02 cubic inch (0.3 cc) of fluid from your vehicle's
master cylinder. Otherwise, both braking systems
won't work well. You could even lose your brakes.
If everything checks out this far, make the brake tap at
the port on the master cylinder that sends the fluid to
the rear brakes. But don't use copper tubing for this.
If you do, it will bend and finally break off. Use steel
brake tubing.
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 ªEngine Exhaustº 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
recirculation because it only recirculates
the air inside your vehicle. See ªComfort
Controlsº in the Index.