towing GMC SIERRA 2019 Owner's Guide

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 271
Alert Seat will pulse five times.
When this Pedestrian Alert occurs,
the brake system may prepare for
driver braking to occur more rapidly
which can cause a brief, mild
deceleration. Continue to apply the
brake pedal as needed. Cruise
control may be disengaged when
the Front Pedestrian Alert occurs.
Automatic Braking
If FPB detects it is about to crash
into a pedestrian directly ahead, and
the brakes have not been applied,
FPB may automatically brake
moderately or brake hard. This can
help to avoid some very low speed
pedestrian crashes or reduce
pedestrian injury. FPB can
automatically brake to detected
pedestrians between 8 km/h (5 mph)
and 80 km/h (50 mph). Automatic
braking levels may be reduced
under certain conditions, such as
higher speeds.
If this happens, Automatic Braking
may engage the Electric Parking
Brake (EPB) to hold the vehicle at a
stop. Release the EPB. A firm pressof the accelerator pedal will also
release Automatic Braking and
the EPB.
{Warning
FPB may alert or automatically
brake the vehicle suddenly in
situations where it is unexpected
and undesired. It could falsely
alert or brake for objects similar in
shape or size to pedestrians,
including shadows. This is normal
operation and the vehicle does
not need service. To override
Automatic Braking, firmly press
the accelerator pedal, if it is safe
to do so.
Automatic Braking can be disabled
through vehicle personalization. See
“Front Pedestrian Detection” in
“Collision/Detection Systems” under
Vehicle Personalization 0170.
{Warning
Using the Front Pedestrian
Braking system while towing a
trailer could cause you to lose
control of the vehicle and crash.
Turn the system to Alert or Off
when towing a trailer.
Cleaning the System
If FPB does not seem to operate
properly, cleaning the outside of the
windshield in front of the rearview
mirror may correct the issue.
Side Blind Zone
Alert (SBZA)
If equipped, the SBZA system is a
lane-changing aid that assists
drivers with avoiding crashes that
occur with moving vehicles in the
side blind zone (or spot) areas.
When the vehicle is in a forward
gear, the left or right side mirror
display will light up if a moving
vehicle is detected in that blind
zone. If the turn signal is activated

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 273
Left Side MirrorDisplayRight Side Mirror Display
When the vehicle is started, both
outside mirror LCA displays will
briefly come on to indicate the
system is operating. When the
vehicle is in a forward gear, the left
or right side mirror display will light
up if a moving vehicle is detected in
the next lane over in that blind zone
or rapidly approaching that zone.
If the turn signal is activated in the
same direction as a detected
vehicle, this display will flash as an
extra warning not to change lanes.
LCA is disabled when the trailer
connection status is displayed.
A DIC message may display. The
SBZA system still operates. LCA can be disabled through
vehicle personalization. When you
disable LCA, SBZA is also disabled.
See
Vehicle Personalization 0170.
If LCA is disabled by the driver, the
LCA mirror displays will not light up.When the System Does Not
Seem to Work Properly
The LCA system requires some
driving for the system to calibrate to
maximum performance. This
calibration may occur more quickly if
the vehicle is driving on a straight
highway road with traffic and
roadside objects (e.g., guardrails,
barriers).
LCA displays may not come on
when passing a vehicle quickly, for
a stopped vehicle, or when towing a
trailer. The LCA detection zones
that extend back from the side of
the vehicle do not move further back
when a trailer is towed. Use caution
while changing lanes when towing a
trailer. LCA may alert to objects
attached to the vehicle, such as a
trailer, bicycle, or object extending
out to either side of the vehicle. Attached objects may also interfere
with the detection of vehicles. This
is normal system operation; the
vehicle does not need service.
LCA may not always alert the driver
to vehicles in the next lane over,
especially in wet conditions or when
driving on sharp curves. The system
does not need to be serviced. The
system may light up due to
guardrails, signs, trees, shrubs, and
other non-moving objects. This is
normal system operation; the
vehicle does not need service.
LCA may not operate when the LCA
sensors in the left or right corners of
the rear bumper are covered with
mud, dirt, snow, ice, or slush, or in
heavy rainstorms. For cleaning
instructions, see "Washing the
Vehicle" under
Exterior Care0408.
If the DIC still displays the system
unavailable message after cleaning
both sides of the vehicle toward the
rear corners of the vehicle, see your
dealer.
If the LCA displays do not light up
when moving vehicles are in the
side blind zone or are rapidly

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 275
Warning (Continued)
occur. Always keep the
windshield, headlamps, and
camera sensors clean and in
good repair. Do not use LKA in
bad weather conditions.
{Warning
Using LKA while towing a trailer
or on slippery roads could cause
loss of control of the vehicle and
a crash. Turn the system off.
How the System Works
The LKA camera sensor is on the
windshield ahead of the rearview
mirror.
To turn LKA on and off, press
A
on the center stack.When on,
Ais green if LKA is
available to assist and provide LDW
alerts. It may assist by gently
turning the steering wheel and
display
Aas amber if the vehicle
approaches a detected lane marking
without using a turn signal in that
direction. It may also provide an
LDW alert by flashing
Aamber
as the lane marking is crossed.
Additionally, there may be three
beeps, or the driver seat may pulse
three times, on the right or left,
depending on the lane departure
direction.
Take Steering
The LKA system does not
continuously steer the vehicle.
If LKA does not detect active driver
steering, an alert, chime, or DIC
message may be provided. Move
the steering wheel to dismiss.
When the System Does Not
Seem to Work Properly
The system performance may be
affected by:
. Close vehicles ahead.
. Sudden lighting changes, such
as when driving through tunnels.
. Banked roads.
. Roads with poor lane markings,
such as two-lane roads.
If the LKA system is not functioning
properly when lane markings are
clearly visible, cleaning the
windshield may help.
A camera blocked message may
display if the camera is blocked.
Cleaning the outside of the
windshield behind the rearview
mirror may correct the issue. Some
driver assistance systems may have
reduced performance or not work at
all. An LKA or LDW unavailable
message may display if the systems
are temporarily unavailable. This
message could be due to a blocked
camera. The LKA system does not

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 281
Trailer Towing
General Towing
Information
Only use towing equipment that has
been designed for the vehicle.
Contact your dealer or trailering
dealer for assistance with preparing
the vehicle to tow a trailer. Read the
entire section before towing a trailer.
To tow a disabled vehicle, see
Towing the Vehicle0403. To tow
the vehicle behind another vehicle
such as a motor home, see
Recreational Vehicle Towing 0404.
Driving Characteristics
and Towing Tips
{Warning
You can lose control when towing
a trailer if the correct equipment is
not used or the vehicle is not
driven properly. For example,
if the trailer is too heavy or the
(Continued)
Warning (Continued)
trailer brakes are inadequate for
the load, the vehicle may not stop
as expected. You and others
could be seriously injured. The
vehicle may also be damaged,
and the 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 for advice and
information about towing a trailer
with the vehicle.
Driving with a Trailer
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.
When towing a trailer:
.
Become familiar with and follow
all state and local laws that
apply to trailer towing. These
requirements vary from state to
state.
. State laws may require the use
of extended side view mirrors.
Even if not required, you should
install extended side view
mirrors if your visibility is limited
or restricted while towing.
. Do not tow a trailer during the
first 800 km (500 mi) of vehicle
use to prevent damage to the
engine, axle, or other parts.
. It is recommended to perform
the first oil change before heavy
towing.
. During the first 800 km (500 mi)
of trailer towing, do not drive
over 80 km/h (50 mph) and do
not make starts at full throttle.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
282 Driving and Operating
.Vehicles can tow in D (Drive).
Tow/Haul Mode is recommended
for heavier trailers. See Tow/
Haul Mode 0238. If the
transmission downshifts too
often, a lower gear may be
selected using Manual Mode.
See Manual Mode 0235.
If equipped, the following driver
assistance features should be
turned off when towing a trailer:
. Cruise Control
. Lane Keep Assist (LKA)
. Park Assist
. Reverse Automatic
Braking (RAB)
If equipped, the following driver
assistance features should be
turned to alert or off when towing a
trailer:
. Forward Automatic
Braking (FAB)
. Intelligent Brake Assist (IBA)
. Front Pedestrian Braking (FPB) If equipped with Lane Change Alert
(LCA), the LCA detection zones that
extend back from the side of the
vehicle do not move further back
when a trailer is towed. Use caution
while changing lanes when towing a
trailer.
If equipped with Rear Cross Traffic
Alert (RCTA), use caution while
backing up when towing a trailer, as
the RCTA detection zones that
extend out from the back of the
vehicle do not move further back
when a trailer is towed.
{Warning
To prevent serious injury or death
from carbon monoxide (CO),
when towing a trailer:
. Do not drive with the
liftgate, trunk/hatch,
or rear-most window open.
. Fully open the air outlets on
or under the instrument
panel.
(Continued)
Warning (Continued)
.Adjust the climate control
system to a setting that
brings in only outside air.
See “Climate Control
Systems” in the Index.
For more information about
carbon monoxide, see Engine
Exhaust 0232.
Towing a trailer requires experience.
The combination of the vehicle and
trailer is longer and not as
responsive as the vehicle itself. Get
used to the handling and braking of
the combination by driving on a
level road surface before driving on
public roads.
The trailer structure, the tires, and
the brakes must all be rated to carry
the intended cargo. Inadequate
trailer equipment can cause the
combination to operate in an
unexpected or unsafe manner.
Before driving, inspect all trailer
hitch parts and attachments, safety
chains, electrical connectors, lamps,

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 283
tires, and mirrors. SeeTowing
Equipment 0290. If the trailer has
electric brakes, start the
combination moving and then
manually apply the trailer brake
controller to check the trailer brakes
work. During the trip, occasionally
check that the cargo and trailer are
secure and that the lamps and any
trailer brakes are working.
Towing with a Stability Control
System
When towing, the stability control
system might be heard. The system
reacts to vehicle movement caused
by the trailer, which mainly occurs
during cornering. This is normal
when towing heavier trailers.
Following Distance
Stay at least twice as far behind the
vehicle ahead as you would when
driving without a trailer. This can
help to avoid heavy braking and
sudden turns.
Passing
More passing distance is needed
when towing a trailer. The
combination of the vehicle and
trailer will not accelerate as quickly
and is much longer than the vehicle
alone. It is necessary to go much
farther beyond the passed vehicle
before returning to the lane. Pass
on level roadways. Avoid passing
on hills if possible.
Backing Up
Hold the bottom of the steering
wheel with one hand. To move the
trailer to the left, move that hand to
the left. To move the trailer to the
right, move that hand to the right.
Always back up slowly and,
if possible, have someone
guide you.
Making Turns
Caution
Turn more slowly and make wider
arcs when towing a trailer to
prevent damage to your vehicle.
Making very sharp turns could
cause the trailer to contact the
vehicle.
Make wider turns than normal when
towing, so trailer will not go over soft
shoulders, over curbs, or strike road
signs, trees, or other objects.
Always signal turns well in advance.
Do not steer or brake suddenly.
Driving on Grades
Reduce speed and shift to a lower
gear before starting down a long or
steep downhill grade. If the
transmission is not shifted down, the
brakes may overheat and result in
reduced braking efficiency.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
284 Driving and Operating
The vehicle can tow in D (Drive).
Shift the transmission to a lower
gear if the transmission shifts too
often under heavy loads and/or hilly
conditions.
When towing at higher altitudes,
engine coolant will boil at a lower
temperature than at lower altitudes.
If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the
vehicle could show signs similar to
engine overheating. To avoid this,
let the engine run, preferably on
level ground, with the transmission
in P (Park) for a few minutes before
turning the engine off. If the
overheat warning comes on, see
Engine Overheating0336.
Viewing Systems
If equipped, the viewing systems on
the vehicle can improve visibility
while hitching, backing, and driving
with a trailer. See Driver Assistance
Systems 0258.
Parking on Hills
{Warning
To prevent serious injury or death,
always park your vehicle and
trailer on a level surface when
possible.
When parking your vehicle and your
trailer on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn
the wheels into the curb if
facing downhill or into traffic if
facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, gradually release the
brake pedal to allow the chocks
to absorb the load of the trailer.
4. Reapply the brake pedal. Then apply the parking brake and
shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
.Start the engine.
. Shift into a gear.
. Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Launching and Retrieving
a Boat
Backing the Trailer into the Water
{Warning
.Have all passengers get out
of the vehicle before
backing onto the sloped part
of the ramp. Lower the
driver and passenger side
windows before backing
onto the ramp. This will
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
286 Driving and Operating
the drive mode that is
appropriate for the road
conditions.
Caution
If the vehicle tires begin to spin
and the vehicle begins to slide
toward the water, remove your
foot from the accelerator pedal
and apply the brake pedal. Seek
help to have the vehicle towed up
the ramp.
Maintenance when Trailer
Towing
The vehicle needs service more
often when used to tow trailers. See
Maintenance Schedule0420. It is
especially important to check the
engine oil, axle lubricant, belts,
cooling system, and brake system
before and during each trip.
Check periodically to see that all
nuts and bolts on the trailer hitch
are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See Engine Overheating
0 336.
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, and
how frequently the vehicle is used to
tow a trailer.
Trailer Weight Ratings
When towing a trailer, the combined
weight of the vehicle, vehicle
contents, trailer, and trailer contents

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 287
must be below all of the maximum
weight ratings for the vehicle,
including:
.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
See “Weight-Distributing Hitch
Adjustment” underTowing
Equipment 0290 to determine if
equalizer bars are required to obtain
the maximum trailer weight rating.
See “Trailer Brakes” underTowing
Equipment 0290 to determine if
brakes are required based on your
trailer's weight.
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. A trailering information label on the
driver's side door B-pillar shows tow
rating information for the vehicle.
{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.
Gross Combined Weight
Rating (GCWR)
GCWR is the total allowable weight
of the completely loaded vehicle
and trailer including any fuel,
passengers, cargo, equipment, and
accessories. Do not exceed the
GCWR for your vehicle. The GCWR
for the vehicle is on the Trailering
Information Label.
To check that the weight of the
vehicle and trailer are within the
GCWR for the vehicle, follow these
steps:
1. Start with the "curb weight" from the Trailering Information
Label.
2. Add the weight of the trailer loaded with cargo and ready
for the trip.
3. Add the weight of all passengers.
4. Add the weight of all cargo in the vehicle.
5. Add the weight of hitch hardware such as a draw bar,
ball, load equalizer bars,
or sway bars.
6. Add the weight of any accessories or aftermarket
equipment added to the
vehicle.
The resulting weight cannot exceed
the GCWR value shown on the
Trailering Information Label.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
290 Driving and Operating
weights and distribution are
appropriate for your vehicle. If the
trailer weight is too high, it may be
possible to transfer some of the
cargo into your vehicle. If the trailer
tongue weight is too high or too low,
it may be possible to rearrange
some of the cargo inside of the
trailer.
Do not exceed the maximum
allowable tongue weight for the
vehicle. Use the shortest hitch
extension that will position the hitch
ball closest to the vehicle. This will
help reduce the effect of trailer
tongue weight on the trailer hitch
and rear axle.
If a cargo carrier is used in the
trailer hitch receiver, choose a
carrier that positions the load as
close to the vehicle as possible.
Make sure the total weight,
including the carrier, is no more than
half of the maximum allowable
tongue weight for the vehicle or
227 kg (500 lb), whichever is less.Rear Gross Axle Weight Rating
(GAWR-RR)
The GAWR-RR is the total weight
that can be supported by the rear
axle of the vehicle. Do not exceed
the GAWR-RR for the vehicle, with
the tow vehicle and trailer fully
loaded for the trip including the
weight of the trailer tongue. If using
a weight-distributing hitch, do not
exceed the GAWR-RR before
applying the weight distribution
spring bars.
The GAWR-RR for the vehicle is on
the Trailering Information Label.Ask your dealer for trailering
information or assistance.
Towing Equipment
Hitches
Always use the correct hitch
equipment for your vehicle.
Crosswinds, large trucks going by,
and rough roads can affect the
trailer and the hitch.
Proper hitch equipment for your
vehicle helps maintain control of the
vehicle-trailer combination. Many
trailers can be towed using a
weight-carrying hitch which has a
coupler latched to the hitch ball, or a
tow eye latched to a pintle hook.
Other trailers may require a
weight-distributing hitch that uses
spring bars to distribute the trailer
tongue weight between your vehicle
and trailer axles. See
“Maximum
Trailer Tongue Weight” underTrailer
Towing 0286 for weight limits with
various hitch types.