2010 GMC SIERRA DENALI towing

Towing
Towing Your Vehicle
To avoid damage, the disabled vehicle should be towed
with all four wheels off the ground. Consult your dealer/
retailer or a professional towing service if the disabled
vehicle must be towed. SeeRoadside Assistance
Program on page 8‑7.
To tow the 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 the vehicle
behind another vehicle–such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as “dinghy towing”(towing the vehicle
with all four wheels on the ground) and “dolly towing”
(towing the vehicle with two wheels on the ground and
two wheels up on a device known as a “dolly”).Here are some important things to consider before
recreational vehicle towing:
.What is the towing capacity of the towing vehicle?
Be sure to read the tow vehicle manufacturer's
recommendations.
.What is the distance that will be travelled? Some
vehicles have restrictions on how far and how long
they can tow.
.Is the proper towing equipment going to be used?
See your dealer/retailer or trailering professional
for additional advice and equipment
recommendations.
.Is the vehicle ready to be towed? Just as preparing
the vehicle for a long trip, make sure the vehicle is
prepared to be towed. See
Before Leaving on a
Long Trip on page 5‑25.
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All-Wheel-Drive Vehicles
Dinghy and Dolly Towing
Notice:Towing an all-wheel-drive vehicle with all
four wheels on the ground, or even with only two of
its wheels on the ground, will damage drivetrain
components. Do not tow an all-wheel-drive vehicle
with any of its wheels on the ground.
All-wheel-drive vehicles are not designed to be towed
with any wheels on the ground. If the vehicle must be
towed, see Towing Your Vehicle previously.
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Two-Wheel-Drive Vehicles
Dinghy Towing
Notice:If a two-wheel-drive vehicle is towed with all
four wheels on the ground, the transmission could
be damaged. The repairs would not be covered by
the vehicle warranty. Do not tow a two-wheel-drive
vehicle with all four wheels on the ground.
Two-wheel-drive vehicles should not be towed with all
four wheels on the ground. Two-wheel-drive
transmissions have no provisions for internal lubrication
while being towed. To dolly tow a two‐wheel‐drive vehicle, the vehicle must
be towed with the rear wheels on the dolly. See
“Dolly
Towing (Rear Wheels Off the Ground)” following.
Dolly Towing (Front Wheels Off the Ground)
Notice:If a two-wheel-drive vehicle is towed with
the rear wheels on the ground, the transmission
could be damaged. The repairs would not be
covered by the vehicle warranty. Never tow the
vehicle with the rear wheels on the ground.
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Two-wheel-drive vehicles should not be towed with the
rear wheels on the ground. Two-wheel-drive
transmissions have no provisions for internal lubrication
while being towed.
Dolly Towing (Rear Wheels Off the Ground)
Use the following procedure to dinghy tow a
two-wheel-drive vehicle from the rear:1. Attach the dolly to the tow vehicle following the dolly manufacturer's instructions.
2. Drive the rear wheels onto the dolly. 3. Firmly set the parking brake. See
Parking Brake
on page 3‑34.
4. Put the transmission in P (Park).
5. Secure the vehicle to the dolly following the manufacturer's instructions.
6. Use an adequate clamping device designed for towing to ensure that the front wheels are locked
into the straight position.
7. Turn the ignition to LOCK/OFF.
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Towing a Trailer
Do not tow a trailer during break‐in. SeeNew Vehicle
Break-Inon page 3‑22for more information.
{WARNING:
The driver can lose control when pulling a trailer if
the correct equipment is not used or the vehicle is
not driven properly. For example, if the trailer is
too heavy, the brakes may not work well —or
even at all. The driver and passengers could be
seriously injured. The vehicle may also be
damaged; the resulting repairs would not be
covered by the vehicle warranty. Pull a trailer only
if all the steps in this section have been followed.
Ask your dealer/retailer for advice and information
about towing a trailer with the vehicle. Notice:
Pulling a trailer improperly can damage the
vehicle and result in costly repairs not covered by
the vehicle warranty. To pull a trailer correctly,
follow the advice in this section and see your
dealer/retailer for important information about
towing a trailer with the vehicle.
To identify the trailering capacity of the vehicle, read the
information in “Weight of the Trailer” that appears later
in this section.
Trailering is different than just driving the vehicle by
itself. Trailering means changes in handling,
acceleration, braking, durability and fuel economy.
Successful, safe trailering takes correct equipment, and
it has to be used properly.
The following information has 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
pulling a trailer.
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The ITBC system is powered through the vehicle's
electrical system. Turning the ignition off will also turn
off the ITBC system. The ITBC system is fully functional
only when the ignition is in ON or in RUN.
The ITBC system can only be used with trailers with
electric brakes.
{WARNING:
Connecting a trailer that is not compatible with the
ITBC system may result in reduced or complete
loss of trailer braking. There may be an increase
in stopping distance or trailer instability which
could result in personal injury or damage to the
vehicle, trailer, or other property. An aftermarket
controller may be available for use with trailers
with surge, air or electric‐over‐hydraulic trailer
brake systems. To determine the type of brakes
on the trailer and the availability of controllers,
check with your trailer manufacturer or dealer/
retailer.When trailering, make sure of the following:
.The ITBC system is used only with trailers that are
equipped with electric brakes.
.All applicable local and federal laws and
regulations are followed.
.All electrical and mechanical connections to the
trailer are made correctly.
.The trailer
’s brakes are in proper working
condition.
.The trailer and vehicle are properly loaded for the
towing condition.
The ITBC system is a factory installed item.
Out‐of‐factory installation of this system should not be
attempted. GM is not responsible for warranty or
performance of the system resulting from out‐of‐factory
installation.
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The trailer and the vehicle's brake lamps will come on
when either vehicle braking or manual trailer brakes are
applied.
Trailer Gain Adjustment Procedure
Trailer Gain should be set for a specific trailering
condition and must be adjusted any time vehicle
loading, trailer loading or road surface conditions
change.
Setting the Trailer Gain properly is needed for the best
trailer stopping performance. A trailer that is
over-gained may result in locked trailer brakes. A trailer
that is under-gained may result in not enough trailer
braking. Both of these conditions may result in poorer
stopping and stability of the vehicle and trailer.
Use the following procedure to correctly adjust Trailer
Gain for each towing condition:1. Make sure the trailer brakes are in proper working condition.
2. Connect a properly loaded trailer to the vehicle and make all necessary mechanical and electrical
connections. See Loading the Vehicle
on
page 5‑31for more information. 3. After the electrical connection is made to a trailer
equipped with electric brakes:
.A TRAILER CONNECTED message will be
briefly displayed on the DIC display.
.The Trailer Brake Display Page will appear on
the DIC showing TRAILER GAIN and TRAILER
OUTPUT.
.In the Trailer Output display on the
DIC, “- - - - - -“ will disappear if there is no error
present. Connecting a trailer without electric
brakes will not clear the six dashed lines.
4. Adjust the Trailer Gain by using the gain adjustment (+ / -) buttons on the Trailer Brake
Control Panel.
5. Drive the vehicle with the trailer attached on a level road surface representative of the towing
condition and free of traffic at about 20 to 25 mph
(32 to 40 km/h) and fully apply the Manual Trailer
Brake Apply lever.
Adjusting trailer gain at speeds lower than
20 to 25 mph (32 to 40 km/h) may result in an
incorrect gain setting.
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6. Adjust the Trailer Gain to just below the point oftrailer wheel lock-up, indicated by trailer wheel
squeal or tire smoke when a trailer wheel locks.
Trailer wheel lock-up may not occur if towing a
heavily loaded trailer. In this case, adjust the
Trailer Gain to the highest allowable setting for the
towing condition.
7. Re-adjust Trailer Gain any time vehicle loading, trailer loading or road surface conditions change or
if trailer wheel lock-up is noticed at any time while
towing.
Other ITBC Related DIC Messages
In addition to displaying TRAILER GAIN and TRAILER
OUTPUT through the DIC, trailer connection and ITBC
system status is displayed in the DIC.
TRAILER CONNECTED –This message will be briefly
displayed when a trailer with electric brakes is first
connected to the vehicle. This message will
automatically turn off in about ten seconds. The driver
can also acknowledge this message before it
automatically turns off. CHECK TRAILER WIRING
–This message will be
displayed if:
1. The ITBC system first determines connection to a trailer with electric brakes and then the trailer
harness becomes disconnected from the vehicle.
If the disconnect occurs while the vehicle is
stationary, this message will automatically turn off
in about thirty seconds. This message will also turn
off if the driver acknowledges this message off or if
the trailer harness is re-connected.
If the disconnect occurs while the vehicle is
moving, this message will continue until the ignition
is turned off. This message will also turn off if the
driver acknowledges this message off or if the
trailer harness is re-connected.
2. There is an electrical fault in the wiring to the electric trailer brakes. This message will continue
as long as there is an electrical fault in the trailer
wiring. This message will also turn off if the driver
acknowledges this message off.
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