brakes GMC SIERRA 2019 Service Manual

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 297
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
displays.
. 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 right to apply the
trailer ’s electric brakes independent
of the vehicle’s brakes. Use this
lever to adjust Trailer Gain to
achieve 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.
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.
Adjusting Trailer Gain at
speeds lower than 32 to
40 km/h (20 to 25 mph) may
result in an incorrect gain
setting.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
298 Driving and Operating
2. Adjust the Trailer Gain, usingthe 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.
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 from 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
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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 299
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/Electronic
Stability Control (ESC) 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 vehiclebrakes 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/ESC may also apply the
trailer brakes.
If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak/
ESC warning light will flash on the
instrument cluster. Reduce vehicle
speed by gradually removing your
foot from the accelerator. If trailer
sway continues, StabiliTrak/ESC
can reduce engine torque to help
slow the vehicle. TSC will not
function if StabiliTrak/ESC is turned
off. See
Traction Control/Electronic
Stability Control 0247.
{Warning
Trailer sway can result in a crash
and in serious injury or death,
even if the vehicle is equipped
with TSC.
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. See Towing
Equipment 0290 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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
300 Driving and Operating
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 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 may have
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:
(Continued)
Warning (Continued)
.Ask the device or trailer
manufacturer if the device
has been thoroughly tested
for compatibility with the
make, model, and year of
your vehicle and any
optional equipment installed
on your vehicle.
. Before driving, check the
trailer brakes are working
properly, if equipped. Drive
the vehicle with the trailer
attached on a level road
surface that is free of traffic
at about 32-40 km/h
(20-25 mph) and fully apply
the manual trailer brake
apply lever. Also, check the
trailer brake lamps and
other lamps are functioning
correctly.
. If the trailer brakes are not
operating properly at any
time, or if a DIC message
indicates problems with the
(Continued)
Warning (Continued)
trailer connections or trailer
brakes, carefully pull the
vehicle over to the side of
the road when traffic
conditions allow.
Trailer Tires
Special Trailer (ST) tires differ from
vehicle tires. Trailer tires are
designed with stiff sidewalls to help
prevent sway and to support heavy
loads. These features can make it
difficult to determine if the trailer tire
pressures are low only based on a
visual inspection.
Always check all trailer tire
pressures before each trip when the
tires are cool. Low trailer tire
pressure is a leading cause of trailer
tire blow-outs.
If the vehicle is equipped with a
trailer tire pressure monitoring
system, see the trailer tire pressure
monitoring system description and
the trailering app.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
304 Driving and Operating
Average Fuel Economy
Touch to view the average fuel
economy of the vehicle while the
Trailer Profile is active.
Transmission Temperature
Touch to view the temperature of
the transmission fluid graphic. The
graphic will indicate a dangerous
level if the temperature is at
130 °C–150 °C (270 °F–300 °F).
Connections
1. Connections Status Page
2. Light Test Start Button
3. Trailer Electrical Diagnostics
Connections OK
If all of the trailer connections are
detected (Daytime Running Lights,
Left Turn Signal Light, Right Turn
Signal Light, Reverse Lights, and
Electric Brakes, if equipped), the
view will display OK.
Connection Problem
If any of the trailer connections are
not detected, a message about the
connection issue will appear on the
Driver Information Center (DIC). The
infotainment display will also show
the connection issue in the
Connection Status view.
Diagnose View
Touch Diagnose to see more
information about the connection
problem.
This view will display the names of
the trailer connector pins, a graphic
of the trailer connector, and a
graphic of the back of the trailer.Any connector pin that failed will be
amber color, and the location of the
corresponding connection will be
highlighted on the graphic of the
back of the trailer.
The Running Lights connection may
not detect partial outages. Activate
the light test to check all trailer
lamps. See
“Light Test”following.
If the trailer is not equipped with
reverse lights or electric brakes and
you are receiving failure messages
in the DIC or on this view, turn off
the Reverse Lights Alert or the
Electric Brakes Alert setting in the
trailer ’s profile page.
Light Test
Touch Start Light Test to cycle the
trailer lights on and off to determine
if they are working. The test follows
this sequence: 1. The running lights turn on first and remain on throughout the
sequence.
2. The brake lights turn on for about two seconds.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 307
The Custom Trailer Profiles and
Guest Trailer are in order of the
most frequently used.
All personalization features are
based on the settings for each
driver in vehicle personalization.
The list of Trailer Profiles is based
on vehicle personalization settings.
Guest Trailer
If the Guest Trailer Profile is the
active Trailer Profile, trailer
detection, connections status,
security, and the Tow/Haul reminder
alerts can be sent. The system will
not track total mileage or fuel
economy, but the system will track
trip mileage and fuel economy if the
Guest Trailer Profile is active. The
Trailer Tire Pressure Monitoring
System or maintenance reminders
cannot be set up for a Guest Trailer
Profile. The Guest Trailer Profile
cannot be edited.
Touch
pto learn more about the
Guest Trailer option. No Trailer Connected
When there is no trailer connected,
Trailer Profiles cannot be activated
but most options can be edited.
Trailer Brake Gain Memory
The system can memorize the brake
gain setting of a Trailer Profile or a
Guest Trailer Profile. When a Trailer
Profile or Guest Trailer Profile is
selected, and a brake gain setting is
set for that Trailer Profile, a quick
notice will appear to indicate that
the system has recalled that
profile’s brake gain setting.
If a Trailer Profile is already active
and the brake gain setting had been
set for that Trailer Profile, the quick
notice will trigger whenever the
ignition is turned on.
If there was an error in setting the
brake gain for a Trailer Profile, there
will be a notification. This pop-up
will not appear if the Guest Trailer
Profile is active or if there is no
trailer connected.Trailer brake gain should be set for
a specific trailering condition and
must be adjusted anytime vehicle
loading, trailer loading, or road
surface conditions change.
See
“Trailer Gain Adjustment
Procedure” for information about the
gain setting procedure.
Editing a Trailer Profile
Trailer Profile View
Touch to edit any of the following
options in the Trailer Profile view:
. Trailer Name
. Hitch Type
. Trailer Type
. Tire Pressure Setup
. Maintenance Reminders
. Mileage
. Average Fuel Economy
. Reverse Lights Alert
. Electric Brakes Alert

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 309
Maintenance Reminders
Touch to view a list of maintenance
reminders for the Trailer Profile.
Touch a reminder to view, reset,
delete, or edit it.
Reset Reminder
Touch Maintenance Complete in the
reminder view to reset the reminder.
On the pop-up, touch Reset to reset
the time and mileage values for the
reminder. Touch Cancel to return to
the previous view and nothing will
change.
Edit Reminder
Touch to edit the mileage or time
settings for the reminder. Touch
Save to save the new settings to the
Trailer Profile.
Delete Reminder
Touch to delete the maintenance
reminder. On the pop-up, touch
Delete to delete the reminder or
touch Cancel to return to the
previous view and nothing will
change.New Maintenance Reminder
Touch + New Maintenance
Reminder to set up a new reminder.
Suggested reminders that were
previously set will have checkmarks
next to them. Suggested reminders
that have not been set will have
empty boxes next to them. The
maximum number of reminders
is 10.
Mileage
Touch to edit the Trailer Profile’s
mileage.
Effect on Maintenance Reminders
If the mileage is reset or changed,
and mileage has already
accumulated, any maintenance
reminders that have been set up will
be adjusted accordingly.
Average Fuel Economy
Touch to reset the average fuel
economy for the Trailer Profile.
Touch Reset to change, or touch
Cancel to go back to the
previous view.
Reverse Lights Alert
Turn on to receive failure messages
about the reverse lights. Turn off to
not receive failure messages about
the reverse lights, unless they are
later detected. This setting cannot
be edited when the Trailer Profile is
inactive or when the trailer is
disconnected.
Electric Brakes Alert
Turn on to receive failure messages
about the electric trailer brakes.
Turn off to not receive failure
messages about the electric trailer
brakes, unless they are later
detected. This setting cannot be
edited when the Trailer Profile is
inactive or when the trailer is
disconnected.
Delete Trailer
Touch to delete the Trailer Profile
and all of its settings.
On the pop-up, touch Delete to
delete the Trailer Profile. Touch
Cancel to dismiss the pop-up and
return to the previous view.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
314 Driving and Operating
To calculate the amount of weight
any front accessory, such as a snow
plow, is adding to the front axle, use
this formula:
(W x (A + W.B.)) /W.B.= Weight the
accessory is adding to the
front axle.
Where:W = Weight of added accessory
A = Distance that the accessory
is in front of the front axle
W.B. = Vehicle Wheelbase For example, adding a 318 kg
(700 lb) snow plow actually adds
more than 318 kg (700 lb) to the
front axle. Using the formula, if the
snow plow is 122 cm (4 ft) in front of
the front axle and the wheelbase is
305 cm (10 ft), then:
W = 318 kg (700 lb)
A = 122 cm (4 ft)
W.B. = 305 cm (10 ft)
(W x (A + W.B.)/W.B. =
(318 x (122 + 305))/305 = 445 kg
(980 lb)
This means if the front axle reserve
capacity is more than 445 kg
(980 lb), the snow plow could be
added without exceeding the
front GAWR.
Heavier equipment can be added on
the front of the vehicle if less cargo
or fewer passengers are carried,
or by positioning cargo toward the
rear. This reduces the load on the
front. However, the front GAWR,
rear GAWR, and Gross Vehicle
Weight Rating (GVWR) must never
be exceeded.
{Warning
On some vehicles that have
certain front mounted equipment,
such as a snow plow, it may be
possible to load the front axle to
the front Gross Axle Weight
Rating (GAWR) but not have
enough weight on the rear axle to
have proper braking performance.
If the brakes cannot work
properly, the vehice could crash.
Always follow the snow plow
manufacturer or installer's
recommendation for rear ballast
to ensure a proper front and rear
weight distribution ratio.
Maintaining a proper front and
rear weight distribution ratio is
necessary to provide proper
braking performance.
Total vehicle reserve capacity is the
difference between the GVWR and
the weight of the truck with full fuel
and passengers. It is the amount of
weight that can be added to the
vehicle before reaching the GVWR.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
316 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 317
California Proposition65 Warning . . . . . . . . . . . . . . . . . 318
California Perchlorate Materials Requirements . . . . . 318
Accessories and Modifications . . . . . . . . . . . . . . . . 318
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 319
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 319
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 321
Engine Oil . . . . . . . . . . . . . . . . . . . . 326
Engine Oil Life System . . . . . . . 328
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 330
Engine Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . 330
Engine Air Cleaner/Filter . . . . . . 331
Cooling System . . . . . . . . . . . . . . 332
Engine Overheating . . . . . . . . . . 336
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . 338
Engine Fan . . . . . . . . . . . . . . . . . . . 338 Washer Fluid . . . . . . . . . . . . . . . . . 339
Brakes . . . . . . . . . . . . . . . . . . . . . . . 340
Brake Pad Life System . . . . . . . 340
Brake Fluid . . . . . . . . . . . . . . . . . . . 341
Battery - North America . . . . . . 342
Four-Wheel Drive . . . . . . . . . . . . . 345
Front Axle . . . . . . . . . . . . . . . . . . . . 345
Rear Axle . . . . . . . . . . . . . . . . . . . . 346
Noise Control System . . . . . . . . 347
Starter Switch Check . . . . . . . . . 348
Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . . . 348
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 348
Wiper Blade Replacement . . . . 349
Windshield Replacement . . . . . 350
Gas Strut(s) . . . . . . . . . . . . . . . . . . 350
Headlamp Aiming
Front Headlamp Aiming . . . . . . 351
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 351
Halogen Bulbs . . . . . . . . . . . . . . . . 351
LED Lighting . . . . . . . . . . . . . . . . . 352
Headlamps, Front Turn Signal, Sidemarker, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . . . 352
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 352 Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 353
License Plate Lamp . . . . . . . . . . 354
Electrical System
Electrical System Overload . . . 354
Fuses and Circuit Breakers . . . 355
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 355
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 359
Instrument Panel Fuse Block (Left) . . . . . . . . . . . . . . . . . 361
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 363
All-Season Tires . . . . . . . . . . . . . . 364
Winter Tires . . . . . . . . . . . . . . . . . . 364
Low-Profile Tires . . . . . . . . . . . . . 365
All-Terrain Tires . . . . . . . . . . . . . . . 365
Tire Sidewall Labeling . . . . . . . . 365
Tire Designations . . . . . . . . . . . . . 368
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 369
Tire Pressure . . . . . . . . . . . . . . . . . 372
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 373
Tire Pressure Monitor
System . . . . . . . . . . . . . . . . . . . . . . 374

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
318 Vehicle Care
California Proposition
65 Warning
{Warning
Most motor vehicles, including
this one, as well as many of its
service parts and fluids, contain
and/or emit chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Engine
exhaust, many parts and
systems, many fluids, and some
component wear by-products
contain and/or emit these
chemicals. For more information
go to www.P65Warnings.ca.gov/
passenger-vehicle.
See Battery - North America 0342
and
Jump Starting - North America
0 400 and the back cover.
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, seat belt pretensioners,
and lithium batteries contained in
Remote Keyless Entry transmitters,
may contain perchlorate materials.
Special handling may be necessary.
For additional information, see
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and
Modifications
Adding non-dealer accessories or
making modifications to the vehicle
can affect vehicle performance and
safety, including such things as
airbags, braking, stability, ride and
handling, emissions systems,
aerodynamics, durability, and
electronic systems like antilock
brakes, traction control, and stability
control. These accessories or
modifications could even cause
malfunction or damage not covered
by the vehicle warranty. Damage to suspension components
caused by modifying vehicle height
outside of factory settings will not be
covered by the vehicle warranty.
Damage to vehicle components
resulting from modifications or the
installation or use of non-GM
certified parts, including control
module or software modifications, is
not covered under the terms of the
vehicle warranty and may affect
remaining warranty coverage for
affected parts.
GM Accessories are designed to
complement and function with other
systems on the vehicle. See your
dealer to accessorize the vehicle
using genuine GM Accessories
installed by a dealer technician.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle 098.