2007 CHEVROLET SILVERADO tow

Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important
weight to measure because it affects the total
or gross weight of your vehicle. The Gross Vehicle
Weight (GVW) includes the curb weight of the
vehicle, any cargo you may carry in it, and
the people who will be riding in the vehicle. If you
have a lot of options, equipment, passengers
or cargo in your vehicle, it will reduce the tongue
weight your vehicle can carry, which will also
reduce the trailer weight your vehicle can tow.
And if you will tow a trailer, you must add
the tongue load to the GVW because your vehicle
will be carrying that weight, too. SeeLoading
Your Vehicle on page 427for more information
about your vehicle’s maximum load capacity.The trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight,
up to a maximum of 600 lbs (272 kg) for the
1500 or 2500 series, and up to a maximum of
750 lbs (340 kg) for the 2500 HD or 3500 series
with a weight carrying hitch. The trailer tongue
weight (A) should be 10 percent to 15 percent of
the total loaded trailer weight, up to a maximum
of 1,000 lbs (453 kg) for the 1500 series and up to
a maximum of 1,500 lbs (680 kg) for the 2500,
2500 HD or 3500 series with a weight distributing
hitch.
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Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the
upper limit for cold tires. You’ll nd these numbers
on the Certication label at the rear edge of the
driver’s door or see Loading Your Vehicle for more
information. Then be sure you don’t go over the
GVW limit for your vehicle, or the GAWR, including
the weight of the trailer tongue. If you use a
weight distributing hitch, make sure you don’t go
over the rear axle limit before you apply the weight
distribution spring bars.
Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough
roads are a few reasons why you’ll need the
right hitch.
Weight-Distributing Hitches and Weight
Carrying Hitches
A:Body to Ground Distance
B:Front of Vehicle
When using a weight-distributing hitch, the hitch
must be adjusted so the distance (A) remains
the same both before and after coupling the trailer
to the tow vehicle.
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If you use a step-bumper hitch, the bumper could
be damaged in sharp turns. Make sure there is
ample room when turning to avoid contact between
the trailer and the bumper.
If you will be pulling a trailer that, when loaded,
will weigh more than 5,000 lbs (2 270 kg) be sure
to use a properly mounted weight-distributing
hitch and sway control of the proper size.
This equipment is very important for proper
vehicle loading and good handling when driving.
Always use a sway control if the trailer will weigh
more than these limits. You can ask a hitch
dealer about sway controls.Fifth Wheel and Gooseneck Trailering
Fifth wheel and gooseneck trailers can be used
with many pickup models. These trailers place a
larger percentage of the weight (kingpin weight)
on the tow vehicle than conventional trailers.
Make sure this weight does not cause the vehicle
to exceed GAWR or GVWR.
Fifth wheel or gooseneck kingpin weight should be
15 to 25 percent of the trailer weight up to the
maximum amount specied in the trailering chart
for your vehicle. See “Weight of the Trailer” in
this section for more information.
The hitch should be located in the pickup bed so
that it’s centerline is over or slightly in front of the
rear axle. Take care that it is not so far forward that
it will contact the back of the cab in sharp turns.
This is especially important for short box pickups.
Trailer pin box extensions and sliding fth wheel
hitch assemblies can help this condition. There
should be at least six inches of clearance between
the top of the pickup box and the bottom of the
trailer shelf that extends over the box.
Make sure the hitch is attached to the tow vehicle
frame rails. Do not use the pickup box for support.
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Safety Chains
You should always attach chains between your
vehicle and your trailer. Cross the safety
chains under the tongue of the trailer to help
prevent the tongue from contacting the road if it
becomes separated from the hitch. Instructions
about safety chains may be provided by the hitch
manufacturer or by the trailer manufacturer.
If you are towing a trailer up to 5,000 lbs (2 271 kg)
with a factory-installed step bumper, you may
attach the safety chains to the attaching points on
the bumper. If you are towing a trailer up to
your vehicle’s trailer rating limit you may attach
the safety chains to the attaching point on the hitch
platform. If you are towing with an aftermarket
hitch follow the trailer or hitch manufacturer’s
recommendation for attaching safety chains.
Always leave just enough slack so you can turn
with your rig. Never allow safety chains to drag on
the ground.
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.
If your vehicle is equipped with StabiliTrak
®,
your trailer cannot tap into the vehicle’s hydraulic
brake system.
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 uid 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 uid to the rear brakes. But don’t use
copper tubing for this. If you do, it will bend
and nally break off. Use steel brake tubing.
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The ITBC system can only be used with trailers
with electric brakes.
{CAUTION:
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 your 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 your trailer and the availability of
controllers, check with your trailer
manufacturer or dealer.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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Manual Trailer Brake Apply
The Manual Trailer Brake Apply Lever is located on
the Trailer Brake Control Panel and is used to apply
the trailer’s electric brakes independent of your
vehicle’s brakes. This lever is used in the Trailer
Gain Adjustment Procedure to properly adjust the
power output to the trailer brakes. Sliding the lever
to the left will apply only the trailer brakes. The
power output to the trailer is indicated in the Trailer
Brake Display Page in the DIC. If your vehicle’s
service brakes are applied while using the Manual
Trailer Brake Apply Lever, the trailer output power
will be the greater of the two.
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 specic 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 notenough 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. SeeLoading Your
Vehicle on page 427for more information.
3. After the electrical connection is made to a
trailer equipped with electric brakes:
A TRAILER CONNECTED message will be
briey 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.
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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.
6. Adjust the Trailer Gain to just below the point
of trailer wheel lock-up, indicated by trailer
wheel squeal or puffs of 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 you notice trailer wheel
lock-up at any time while you are 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
briey displayed when a trailer with electric brakes
is rst 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 rst 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.
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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 cannot see or smell CO. It
can cause unconsciousness or death. See
Engine Exhaust on page 169. 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.
CAUTION: (Continued)
CAUTION: (Continued)

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 the climate control
setting for maximum air because it
only recirculates the air inside your
vehicle. SeeClimate Control System
(With Air Conditioning ) on page 236
orClimate Control System (Heater
Only) on page 239.
Towing a trailer requires a certain amount of
experience. Before setting out for the open road,
you’ll want to get to know your rig. Acquaint
yourself with the feel of handling and braking with
the added weight of the trailer. And always
keep in mind that the vehicle you are driving is
now a good deal longer and not nearly as
responsive as your vehicle is by itself.
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