brake CHEVROLET SILVERADO 3500 2019 Repair Manual

Chevrolet Silverado LD 1500 and Silverado 2500/3500 Owner Manual (GMNA-
Localizing-U.S./Canada-12162993) - 2019 - crc - 4/4/18
298 Driving and Operating
Trailer Towing
If equipped with a diesel engine,
see the Duramax diesel
supplement.
Caution
Towing a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To tow a trailer
correctly, follow the directions in
this section and see your dealer
for important information about
towing a trailer with the vehicle.
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. Read this section
carefully before pulling a trailer.
Trailer Weight
{Warning
Never exceed the towing capacity
for your vehicle.
Safe trailering requires monitoring
the weight, speed, altitude, road
grades, outside temperature,
dimensions of the front of the trailer,
and how frequently the vehicle is
used to tow a trailer.
Trailering Weight Ratings
When towing a trailer, the weight of
the loaded vehicle and trailer must
be within the weight ratings for the
vehicle.
. GCWR: Gross Combined Weight
Rating
. GVWR: Gross Vehicle Weight
Rating
. Maximum Trailer Weight Rating .
GAWR-RR: Gross Axle Weight
Rating-Rear
. Maximum Trailer Tongue Weight
Rating
The only way to be sure the weight
is not exceeding any of these
ratings is to weigh the tow vehicle
and trailer combination, fully loaded
for the trip, getting individual
weights for each of these items.
{Warning
You and others could be seriously
injured or killed if the trailer is too
heavy or the trailer brakes are
inadequate for the load. The
vehicle may be damaged, and the
repairs would not be covered by
the vehicle warranty.
Only tow a trailer if all the steps in
this section have been followed.
Ask your dealer for advice and
information about towing a trailer.

Chevrolet Silverado LD 1500 and Silverado 2500/3500 Owner Manual (GMNA-
Localizing-U.S./Canada-12162993) - 2019 - crc - 4/4/18
308 Driving and Operating
The hitch should be in the pickup
bed so that its 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 fifth-wheel hitch assemblies
may be used. There should be at
least 15 cm (6 in) 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.
Safety Chains
Always attach safety chains
between the vehicle and the trailer.
Instructions about safety chains
may be provided by the hitch
manufacturer or by the trailer
manufacturer.
If the trailer being towed weighs up
to 2 271 kg (5,000 lb) with a
factory-installed step bumper, safety
chains may be attached to theattaching points on the bumper;
otherwise, safety chains should be
attached to holes on the trailer hitch.
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. Always leave enough slack in
the safety chains to allow the
combination to turn. Never allow
safety chains to drag on the ground.
Trailer Brakes
Loaded trailers over 900 kg
(2,000 lb) must be equipped with
brake systems and with brakes for
each axle. Trailer braking equipment
conforming to Canadian Standards
Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State or local regulations may
require trailers to have their own
braking system if the loaded weight
of the trailer exceeds certain
minimums that can vary from state
to state. Read and follow the
instructions for the trailer brakes so
they are installed, adjusted, andmaintained properly. Never attempt
to tap into your vehicle's hydraulic
brake system. If you do, both the
vehicle anti-lock brakes and the
trailer brakes may not function,
which could result in a crash.
Auxiliary Battery
If equipped, the vehicle's auxiliary
battery can be used to supply
electrical power to additional
equipment that may be added, such
as a slide-in camper.
Locate the auxiliary battery
connector under the hood on the
driver's side of the vehicle, next to
the underhood electrical center.
Follow the proper installation
instructions included with any
electrical equipment that is installed.
Caution
To prevent draining the auxiliary
battery, always turn off electrical
equipment when not in use and
do not use any equipment that
(Continued)

Chevrolet Silverado LD 1500 and Silverado 2500/3500 Owner Manual (GMNA-
Localizing-U.S./Canada-12162993) - 2019 - crc - 4/4/18
Driving and Operating 309
Caution (Continued)
may exceed the
maximum amperage rating of
30 amps.
Trailer Wiring Harness
Basic Trailer Wiring
If the vehicle is not equipped with a
trailer connector on the rear bumper,
a 7-wire trailering harness is tied to
the vehicles frame. The harness
requires the installation of a trailer
connector, which is available
through your dealer.
Use only a round, seven-wire
connector with flat blade terminals
meeting SAE J2863 specifications
for proper electrical connectivity.
The seven-wire harness contains
the following trailer circuits:Stop/Turn
Signal Left Yellow/Blue
Stop/Turn
Signal Right Green/Brown Tail/Parking
Lamps
Gray/Brown
Reverse Lamps White/Green
Battery Feed Red/Violet
Ground Black
Electric Trailer
Brake Blue
Heavy-Duty Trailer Wiring Harness
Package
If equipped, the trailer wiring
harness, with a 7-pin connector and
a 4-pin connector, is mounted on
the vehicle's rear bumper.
The trailer connectors contain the
following circuits.
1. Ground
2. Tail Lamps
3. Left Turn/Brake
4. Right Turn/Brake

Chevrolet Silverado LD 1500 and Silverado 2500/3500 Owner Manual (GMNA-
Localizing-U.S./Canada-12162993) - 2019 - crc - 4/4/18
310 Driving and Operating
1. Left Turn/Brake
2. Tail Lamps
3. Reverse Lamps
4. Battery Feed
5. Right Turn/Brake
6. Electric Brakes
7. Ground
If equipped with the fifth wheel/
gooseneck trailer package, the
harness connector is mounted on
the inside of the pickup bed behind
the rear wheel.Camper/Fifth-Wheel Trailer Wiring
Package
For vehicles without the fifth wheel/
gooseneck trailer package, the
seven-wire camper harness is under
the rear bumper, attached to the
frame near the rear crossmember.
A connector must be added to the
wiring harness that connects to the
camper.
The harness contains the following
camper/trailer circuits: Stop/Turn
Signal Left Yellow/Blue
Stop/Turn
Signal Right Green/Brown Tail/Parking
Lamps
Gray/Brown
Reverse Lamps White/Green
Battery Feed Red/Violet
Ground Black
Electric Trailer
Brake Blue
If equipped with the heavy-duty
trailering option, see “Heavy-Duty
Trailer Wiring Harness Package”
earlier in this section. When the
camper-wiring harness is ordered
without the heavy-duty trailering
package, a seven-wire harness with
a seven-pin connector is at the rear
of the vehicle and is tied to the
vehicle's frame.
Electric Brake Control Wiring
Provisions
If the vehicle is not equipped with
an integrated trailer brake controller,
a trailer brake controller needs to be
installed on the vehicle if the trailer
has electric brakes. The brake
controller should be installed by

Chevrolet Silverado LD 1500 and Silverado 2500/3500 Owner Manual (GMNA-
Localizing-U.S./Canada-12162993) - 2019 - crc - 4/4/18
Driving and Operating 311
your dealer or a qualified service
center. If equipped, wiring
provisions for an aftermarket electric
trailer brake controller are included
with the vehicle as part of the trailer
wiring package. The harness
contains the following circuits:Electric Trailer
Brakes Blue
Battery Feed Red/Black or
Red/Blue
Brake Apply
Signal White/Blue
Ground Black
Refer to the aftermarket electric
trailer brake controller owner's
manual to determine wire color
coding of the electric trailer brake
controller. The wire colors on the
brake controller may be different
from the vehicle. The fuse for the
electric trailer brake circuit is in the
engine compartment fuse block, but
the wires may not be connected.
They should be connected by your
dealer or a qualified service center.Trailer Lamps
Always check all trailer lamps are
working at the beginning of each
trip, and periodically on longer trips.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals should will illuminate to
indicate the vehicle is turning,
changing lanes, or stopping. When
towing a trailer, the arrows on the
instrument cluster will illuminate
even if the trailer is not properly
connected or the bulbs are
burned out.
Tow/Haul Mode
For instructions on how to enter
Tow/Haul mode, see Tow/Haul
Mode 0261.
Tow/Haul assists when pulling a
heavy trailer or a large or
heavy load.
Tow/Haul Mode is designed to be
most effective when the vehicle and
trailer combined weight is at least
75% of the vehicle's Gross Combined Weight Rating (GCWR).
See
“Weight of the Trailer” under
Trailer Towing 0298.
Tow/Haul Mode is most useful when
towing a heavy trailer or carrying a
large or heavy load:
. through rolling terrain.
. in stop-and-go traffic.
. in busy parking lots.
Operating the vehicle in Tow/Haul
Mode when lightly loaded or not
towing will not cause damage;
however, it is not recommended and
may result in unpleasant engine and
transmission driving characteristics
and reduced fuel economy.Integrated Trailer Brake
Control System
TThe vehicle may have an
Integrated Trailer Brake Control
(ITBC) system for use with electric
trailer brakes or most electric over
hydraulic trailer brake system

Chevrolet Silverado LD 1500 and Silverado 2500/3500 Owner Manual (GMNA-
Localizing-U.S./Canada-12162993) - 2019 - crc - 4/4/18
312 Driving and Operating
This symbol is on the Trailer Brake
Control Panel on vehicles with an
ITBC system. The power output to
the trailer brakes is proportional to
the amount of vehicle braking. 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 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 StabiliTrak.
If the vehicle’s brake, anti-lock
brake, or StabiliTrak systems are
not functioning properly, the ITBC
system may not function fully or at all. Make sure all of these systems
are fully operational to allow the
ITBC system to function properly.
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/RUN.
{Warning
Connecting a trailer that has an
air brake system may result in
reduced or complete loss of trailer
braking, including increased
stopping distance or trailer
instability which could result in
serious injury, death, or property
damage. Only use the ITBC
system with electric or electric
over hydraulic trailer brake
systems.
Trailer Brake Control Panel
1. Manual Trailer Brake Apply
Lever
2. Trailer Gain Adjustment Buttons
The ITBC control panel is on the
instrument panel to the left of the
steering column. See Instrument
Panel 06. The control panel allows
adjustment to the amount of output,
referred to as Trailer Gain, available
to the trailer brakes and allows
manual application of the trailer
brakes. Use the ITBC control panel

Chevrolet Silverado LD 1500 and Silverado 2500/3500 Owner Manual (GMNA-
Localizing-U.S./Canada-12162993) - 2019 - crc - 4/4/18
Driving and Operating 313
and the DIC trailer brake display
page to adjust and display power
output to the trailer brakes.
Trailer Brake DIC Display Page
The ITBC display page indicates
.Trailer Gain setting
. Output to the trailer brakes
. Trailer connection
. System operational status.
To display
. Scroll through the DIC menu
pages
. Press a Trailer Gain (+) or (−)
button
. Activate the Manual Trailer
Brake Apply Lever
Press a Trailer Gain button to recall
the current Trailer Gain setting.
Each press and release of the gain
buttons will then change the Trailer
Gain setting. TRAILER GAIN:
Press the Trailer Gain (+) or (−) to
adjust. Press and hold to
continuously adjust the Trailer Gain.
To turn the output to the trailer off,
adjust the Trailer Gain setting to 0.0.
This setting can be adjusted from
0.0 to 10.0 with a trailer connected
or disconnected.
TRAILER OUTPUT: This displays
anytime a trailer with electric brakes
is connected. Output to the trailer
brakes is based on the amount of
vehicle braking present and relative
to the Trailer Gain setting. Output is
displayed from 0 to 100% for each
gain setting.
The Trailer Output will indicate
“- - -
- - -” on the Trailer Brake Display
Page whenever the following occur:
. No trailer is connected.
. A trailer without electric brakes
is connected, no DIC message
will display .
A trailer with electric brakes has
become disconnected, a CHECK
TRAILER WIRING message
displays on the DIC
. There is a fault present in the
wiring to the trailer brakes, a
CHECK TRAILER WIRING
message displays on the DIC
. The ITBC system is not working
due to a fault, a SERVICE
TRAILER BRAKE SYSTEM
message displays in the DIC
Manual Trailer Brake Apply Lever
Slide this lever left to apply the
trailer ’s electric brakes independent
of the vehicle’s brakes. Use this
lever to adjust Trailer Gain to
achieve the proper power output to
the trailer brakes. The trailer's and
the vehicle's brake lamps will come
on when either vehicle brakes or
manual trailer brakes are applied
and properly connected.

Chevrolet Silverado LD 1500 and Silverado 2500/3500 Owner Manual (GMNA-
Localizing-U.S./Canada-12162993) - 2019 - crc - 4/4/18
314 Driving and Operating
Trailer Gain Adjustment Procedure
Trailer Gain should be set for a
specific trailering condition and it
must be readjusted anytime vehicle
loading, trailer loading, or road
surface conditions change.
{Warning
Trailer brakes that are
over-gained or under-gained may
not stop the vehicle and the trailer
as intended and can result in a
crash. Always follow the
instructions to set the Trailer Gain
for the proper trailer stopping
performance.
To adjust Trailer Gain for each
towing condition: 1. Drive the vehicle with the trailer attached on a level road
surface representative of the
towing condition and free of
traffic at about 32 - 40 km/h
(20 - 25 mph) and fully apply
the Manual Trailer Brake Apply
Lever. Note
Adjusting Trailer Gain at speeds
lower than 32 to 40 km/h (20 to
25 mph) may result in an incorrect
gain setting.
2. Adjust the Trailer Gain, using the Trailer Gain (+) or (−)
adjustment Buttons, to just
below the point of trailer wheel
lock-up, indicated by trailer
wheel squeal or tire smoke
when a trailer wheel locks.
Note
Trailer wheel lock-up may not occur
if towing a heavily loaded trailer.
Adjust the Trailer Gain to the
highest allowable setting for the
towing condition.
3. Readjust Trailer Gain anytime 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
TRAILER CONNECTED: This
message will briefly display when a
trailer with electric brakes is first
connected to the vehicle. This
message will automatically turn off
in about 10 seconds. This message
can be acknowledged before it
automatically turns off.
CHECK TRAILER WIRING: This
message will display if:
.
The ITBC system first
determines connection to a
trailer with electric brakes and
then the trailer harness becomes
disconnected the vehicle.
If the disconnect occurs while
the vehicle is stationary, this
message will automatically turn
off in about 30 seconds. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected.
If the disconnect occurs while
the vehicle is moving, this
message will continue until the
ignition is turned off. This

Chevrolet Silverado LD 1500 and Silverado 2500/3500 Owner Manual (GMNA-
Localizing-U.S./Canada-12162993) - 2019 - crc - 4/4/18
Driving and Operating 315
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected.
. There is an electrical fault in the
wiring to the 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 it is
acknowledged.
To determine whether the electrical
fault is on the vehicle side or trailer
side of the trailer wiring harness
connection: 1. Disconnect the trailer wiring harness from the vehicle.
2. Turn the ignition off.
3. Wait 10 seconds, then turn the ignition back to RUN.
4. If the CHECK TRAILER WIRING message reappears,
the electrical fault is on the
vehicle side. If the CHECK TRAILER WIRING
message only reappears when
connecting the trailer wiring harness
to the vehicle, the electrical fault is
on the trailer side.
SERVICE TRAILER BRAKE
SYSTEM: This message will display
when there is a problem with the
ITBC system. If this message
continues over multiple ignition
cycles, have the vehicle serviced.
If either the CHECK TRAILER
WIRING or SERVICE TRAILER
BRAKE SYSTEM message displays
while driving, the ITBC system may
not be fully functional or may not
function at all. When traffic
conditions allow, carefully pull the
vehicle over to the side of the road
and turn the ignition off. Check the
wiring connection to the trailer and
turn the ignition back on. If either of
these messages continues, either
the vehicle or trailer needs service.
A GM dealer may be able to
diagnose and repair problems with
the trailer. However, any diagnosis
and repair of the trailer is not
covered under the vehicle warranty. Contact your trailer dealer for
assistance with trailer repairs and
trailer warranty information.
Trailer Sway
Control (TSC)
Vehicles with StabiliTrak have a
Trailer Sway Control (TSC) feature.
Trailer sway is unintended
side-to-side motion of a trailer while
towing. If the vehicle is towing a
trailer and the TSC detects that
sway is increasing, the vehicle
brakes are selectively applied at
each wheel, to help reduce
excessive trailer sway. If equipped
with the Integrated Trailer Brake
Control (ITBC) system, and the
trailer has an electric brake system,
StabiliTrak may also apply the trailer
brakes.

Chevrolet Silverado LD 1500 and Silverado 2500/3500 Owner Manual (GMNA-
Localizing-U.S./Canada-12162993) - 2019 - crc - 4/4/18
316 Driving and Operating
If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak
warning light will flash on the
instrument cluster. Reduce vehicle
speed by gradually removing your
foot from the accelerator. If trailer
sway continues, StabiliTrak can
reduce engine torque to help slow
the vehicle. TSC will not function if
StabiliTrak is turned off. See
Traction Control/Electronic Stability
Control.
{Warning
Trailer sway can result in a crash
and in serious injury or death,
even if the vehicle is equipped
with TSC.(Continued)
Warning (Continued)
If the trailer begins to sway,
reduce vehicle speed by
gradually removing your foot from
the accelerator. Then pull over to
check the trailer and vehicle to
help correct possible causes,
including an improperly or
overloaded trailer, unrestrained
cargo, improper trailer hitch
configuration, or improperly
inflated or incorrect vehicle or
trailer tires. SeeTowing
Equipment 0306 for trailer ratings
and hitch setup
recommendations.
Aftermarket Electronic Trailer
Sway Control Devices
Some trailers may come equipped
with an electronic device designed
to reduce or control trailer sway.
Aftermarket equipment
manufacturers also offer similar
devices that connect to the wiring
between the trailer and the vehicle.
These devices may interfere with the vehicle’
s trailer brake systems
or other systems, including
integrated anti-sway systems,
if equipped. Messages related to
trailer connections or trailer brakes
could appear on the DIC. The
effects of these aftermarket devices
on vehicle handling or trailer brake
performance is not known.
{Warning
Use of aftermarket electronic
trailer sway control devices could
result in reduced trailer brake
performance, loss of trailer
brakes, or other malfunctions, and
result in a crash. You or others
could be seriously injured or
killed. Before using one of these
devices:
. Ask the device or trailer
manufacturer if the device
has been thoroughly tested
for compatibility with the
make, model, and year of
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