
Trailer Brakes
A loaded trailer that weighs more than 2,000 lbs
(900 kg) needs to have its own brake system that is
adequate for the weight of the trailer. Be sure to read
and follow the instructions for the trailer brakes so
they are installed, adjusted and maintained properly.
If the vehicle is equipped with StabiliTrak
®, the
trailer cannot tap into the vehicle’s hydraulic brake
system.
The 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 the vehicle’s
master cylinder. Otherwise, both braking systems
will not work well or at all.
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. Use only steel brake tubing to make
the tap.
Integrated Trailer Brake Control
System
The vehicle may have an
Integrated Trailer Brake
Control (ITBC) system for
electric trailer brakes.
This symbol is located on the Trailer Brake Control
Panel on vehicles with an Integrated Trailer Brake
Control System. The power output to the trailer brakes
is based on the amount of brake pressure being
applied by the vehicle’s brake system. This available
power output to the trailer brakes can be adjusted to
a wide range of trailering situations.
The ITBC system is integrated with the vehicle’s brake,
anti-lock brake and StabiliTrak (if equipped) systems.
In trailering conditions that cause the vehicle’s anti-lock
brake or StabiliTrak systems to activate, power sent
to the trailer’s brakes will be automatically adjusted to
minimize trailer wheel lock-up. This does not imply
that the trailer has the StabiliTrak system.
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Driving with a Trailer
{CAUTION:
When towing a trailer, exhaust gases may collect
at the rear of the vehicle and enter if the liftgate,
trunk/hatch, or rear-most window is open.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
To maximize safety when towing a trailer:
Have the exhaust system inspected for
leaks and make necessary repairs before
starting a trip.
Never drive with the liftgate, trunk/hatch,
or rear-most window open.
Fully open the air outlets on or under the
instrument panel.
Adjust the Climate Control system to a setting
that brings in only outside air and set the fan
speed to the highest setting. See Climate
Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 2-55.Towing a trailer requires a certain amount of
experience. Get to know the rig before setting out for the
open road. Get acquainted 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
longer and not as responsive as the vehicle is by itself.
Before starting, check all trailer hitch parts and
attachments, safety chains, electrical connectors, lamps,
tires and mirror adjustments. If the trailer has electric
brakes, start the vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure the
brakes are working. This checks the electrical connection
at the same time.
During the trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
While towing a trailer or when exposed to long periods
of sunshine, the oor of the truck bed may become
very warm. Avoid putting items in the truck bed
that might be affected by high ambient temperatures.
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Electric Brake Control Wiring
Provisions
These wiring provisions are included with the vehicle as
part of the trailer wiring package. These provisions are
for an electric brake controller. The instrument panel
contains blunt cut wires behind the steering column for
the trailer brake controller. The harness contains the
following wires:
Dark Blue: Brake Signal to Trailer Connector
Red/Black: Battery
Light Blue/White: Brake Switch
White: Ground
It should be installed by your dealer/retailer or a
quali ed service center.
If the vehicle is equipped with an ITBC, the blunt cuts
exist, but are not connected further in the harness.
If an aftermarket trailer brake controller is installed,
the ITBC must be disconnected. Do not power
both ITBC and aftermarket controllers to control
the trailer brakes at the same time.
Auxiliary Battery
The auxiliary battery provision can be used to supply
electrical power to additional equipment that may be
added, such as a slide-in camper. If the vehicle has this
provision, this relay will be located on the drivers side of
the vehicle, next to the underhood electrical center.Be sure to follow the proper installation instructions
that are included with any electrical equipment that
is installed.
Notice:Leaving electrical equipment on for
extended periods will drain the battery. Always turn
off electrical equipment when not in use and do
not use equipment that exceeds the maximum
amperage rating for the auxiliary battery provision.
Trailer Recommendations
Subtract the hitch loads from the Cargo Weight Rating
(CWR). CWR is the maximum weight of the load the
vehicle can carry. It does not include the weight of the
people inside, but you can gure about 150 lbs. (68 kg)
for each passenger. The total cargo load must not be
more than the vehicles CWR.
Weigh the vehicle with the trailer attached, so
the GVWR or GAWR are not exceeded. If using a
weight-distributing hitch, weigh the vehicle without
the spring bars in place.
The best performance is obtained by correctly spreading
out the weight of the load and choosing the correct
hitch and trailer brakes.
For more information seeTowing a Trailer on page 4-51.
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