trailer GMC SIERRA 2021 User Guide
[x] Cancel search | Manufacturer: GMC, Model Year: 2021, Model line: SIERRA, Model: GMC SIERRA 2021Pages: 461, PDF Size: 11.84 MB
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GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Instruments and Controls 135
Ride Height
Touch and the following may display:
.Automatic Entry/Egress
Automatic Entry/Egress
This feature specifies if the vehicle will
automatically lower to make it easier to
enter or exit the vehicle.
Touch Off or On.
Running Boards
Touch and the following may display:
.Automatic Running Boards
.Deploy Running Boards
Automatic Running Boards
This feature specifies the position and use of
the running boards.
Touch Off or On.
Deploy Running Boards
This feature moves the running boards to a
deployed position so they can be used with
the doors closed.
Touch Off or Deploy.
Seating Position
Touch and the following may display:
.Seat Entry Memory
.Seat Exit Memory
Seat Entry Memory
This feature automatically recalls the
previously stored 1 or 2 button positions
when the ignition is changed from off to on
or ACC/ACCESSORY. See Memory Seats049.
Touch Off or On.
Seat Exit Memory
This feature automatically recalls the
previously stored exit button position when
the ignition is changed from on or ACC/
ACCESSORY to off and the driver door is
open. See Memory Seats 049.
Touch Off or On.
Suspension
Touch and the following may display:
.Service Mode
.Alignment Mode Service Mode
This feature disables the air suspension
system and is used to prevent unintended
raising or lowering of the suspension.
Touch Off or On.
Alignment Mode
This feature will optimize the vehicle height
to provide the most accurate wheel
alignment.
Touch Off or On.
Trailering
Touch and the following may display:
.Side Trailer Camera
.Bed View Camera Lighting
Side Trailer Camera
This feature specifies if using the turn signal
during a lane change will also display an
applicable side view of the trailer and
vehicle. See Assistance Systems for Parking
or Backing 0266.
Touch Off or On.
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GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Lighting 147
When the battery's state of charge is low,
the voltage is raised slightly to quickly bring
the charge back up. When the state of
charge is high, the voltage is lowered
slightly to prevent overcharging. The
voltmeter gauge or the voltage display on
the Driver Information Center (DIC),
if equipped, may show the voltage moving
up or down. This is normal. If there is a
problem, an alert will be displayed.
The battery can be discharged at idle if the
electrical loads are very high. This is true for
all vehicles. This is because the generator
(alternator) may not be spinning fast
enough at idle to produce all the power that
is needed for very high electrical loads.
A high electrical load occurs when several of
the following are on, such as: headlamps,
high beams, fog lamps, rear window
defogger, climate control fan at high speed,
heated seats, engine cooling fans, trailer
loads, and loads plugged into accessory
power outlets.EPM works to prevent excessive discharge of
the battery. It does this by balancing the
generator's output and the vehicle's
electrical needs. It can increase engine idle
speed to generate more power, whenever
needed. It can temporarily reduce the power
demands of some accessories.
Normally, these actions occur in steps or
levels, without being noticeable. In rare
cases at the highest levels of corrective
action, this action may be noticeable to the
driver. If so, a DIC message might be
displayed and it is recommended that the
driver reduce the electrical loads as much as
possible.
Battery Power Protection
This feature shuts off the dome and reading
lamps, if they are left on for more than
10 minutes after the ignition is turned off.
The cargo lamp shuts off after 20 minutes.
This prevents the battery from
running down.
Exterior Lighting Battery Saver
The exterior lamps turn off about 10 minutes
after the ignition is turned off, if the parking
lamps or headlamps have been manually
left on. This protects against draining the
battery. To restart the 10-minute timer, turn
the exterior lamp control to the
Oposition
and then back to the
;or2position.
To keep the lamps on for more than
10 minutes, the ignition must be on or in
ACC/ACCESSORY.
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GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
194 Infotainment System
Manage Settings
Audio Volume Limit :Allows the audio
volume limit to be turned on or off. Touch
Set Audio Volume Limit to choose the
maximum allowable audio volume level.
Set Audio Volume Limit : Allows a
maximum radio volume to be set. Use the
arrows to choose the maximum allowable
level for the audio volume.
Teen Driver Speed Limiter : Limits the
maximum speed of the vehicle. When the
speed limiter is turned on and the vehicle is
started with a Teen Driver key, the DIC
displays a message that the top speed is
limited.
On certain vehicles, when the Speed Limiter
is turned ON, the vehicle’s maximum
acceleration will be limited. The DIC will
display a message that the acceleration is
limited.
Teen Driver Speed Warning : Allows the
speed warning to be turned on or off. Touch
Set Teen Driver Speed Warning to set the
warning speed. Set Teen Driver Speed Warning :
Displays a
warning in the DIC when exceeding a
selectable speed. Choose the desired speed
warning level. The speed warning does not
limit the speed of the vehicle.
SiriusXM Explicit Content Filter (if
equipped) : Allows the SiriusXM Explicit
Content Filter to be turned ON or OFF.
When ON, the teen driver will not be able
to listen to SiriusXM stations that contain
explicit content, and the Explicit Content
Filter selection in the Audio Settings will be
unavailable for change.
When Teen Driver is Active:
.If equipped with Buckle to Drive, shifting
out of P (Park) will be prevented if the
driver seat belt, and in some vehicles the
front passenger seat belt, is not buckled.
.The radio will mute when the driver seat
belt, and in some vehicles the front
passenger seat belt, is not buckled. The
audio from any device paired to the
vehicle will also be muted.
.An object placed on the front passenger
seat, such as a briefcase, handbag,
grocery bag, laptop, or other electronic
device, could cause the passenger sensing
system to falsely sense an unbuckled
front passenger and mute the radio. If this happens, remove the object from
the seat. See
Passenger Sensing System
0 66.
.Some safety systems, such as Forward
Collision Alert, if equipped, cannot be
turned off.
.The gap setting for the Forward Collision
Alert and Adaptive Cruise Control,
if equipped, cannot be changed.
.When trying to change a safety feature
that is not configurable in Teen Driver,
the DIC displays a message indicating
that Teen Driver is active and the action
is not available.
.Super Cruise, if equipped, is not available.
.Enhanced Low Fuel Warning (if equipped)
–When the vehicle is low on fuel, the
low fuel light on the instrument cluster
flashes and the DIC low fuel warning
cannot be dismissed.
.Do not tow a trailer.
Report Card
The vehicle owner must secure the driver’s
consent to record certain vehicle data when
the vehicle is driven with a registered Teen
Driver key. There is one Report Card per
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GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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212 Driving and Operating
Filling a Portable Fuel Container . . . . . . . 288
Trailer Towing
General Towing Information . . . . . . . . . . 288
Driving Characteristics andTowing Tips . . . . . . . . . . . . . . . . . . . . . . . . . 288
Trailer Towing . . . . . . . . . . . . . . . . . . . . . . . . . 293
Towing Equipment . . . . . . . . . . . . . . . . . . . . 296
Trailer Sway Control (TSC) . . . . . . . . . . . . 306
Trailering App . . . . . . . . . . . . . . . . . . . . . . . . . 307
Conversions and Add-Ons
Add-On Electrical Equipment . . . . . . . . . . . 318
Adding a Snow Plow or Similar Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . 318
Pickup Conversion to Chassis Cab . . . . . 320
Driving Information
Driving for Better Fuel Economy
Driving habits can affect fuel mileage. Here
are some driving tips to get the best fuel
economy possible:
.Set the climate controls to the desired
temperature after the engine is started,
or turn them off when not required.
.Avoid fast starts and accelerate smoothly.
.Brake gradually and avoid abrupt stops.
.Avoid idling the engine for long periods
of time.
.When road and weather conditions are
appropriate, use cruise control.
.Always follow posted speed limits or
drive more slowly when conditions
require.
.Keep vehicle tires properly inflated.
.Combine several trips into a single trip.
.Replace the vehicle's tires with the same
TPC Spec number molded into the tire's
sidewall near the size.
.Follow recommended scheduled
maintenance.
Distracted Driving
Distraction comes in many forms and can
take your focus from the task of driving.
Exercise good judgment and do not let other
activities divert your attention away from
the road. Many local governments have
enacted laws regarding driver distraction.
Become familiar with the local laws in
your area.
To avoid distracted driving, keep your eyes
on the road, keep your hands on the
steering wheel, and focus your attention on
driving.
.Do not use a phone in demanding driving
situations. Use a hands-free method to
place or receive necessary phone calls.
.Watch the road. Do not read, take notes,
or look up information on phones or
other electronic devices.
.Designate a front seat passenger to
handle potential distractions.
.Become familiar with vehicle features
before driving, such as programming
favorite radio stations and adjusting
climate control and seat settings. Program
all trip information into any navigation
device prior to driving.
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Driving and Operating 223
pressures (4). For more information on
tires and inflation seeTires0360 and
Tire Pressure 0367.
There is also important loading
information on the vehicle Certification/
Tire label. It may show the Gross
Vehicle Weight Rating (GVWR) and the
Gross Axle Weight Rating (GAWR) for
the front and rear axles. See
“Certification/Tire Label” later in this
section.
“Steps for Determining Correct Load Limit–
1.
Locate the statement "The combined
weight of occupants and cargo
should never exceed XXX kg or
XXX lbs." on your vehicle’s placard.
2.Determine the combined weight of
the driver and passengers that will
be riding in your vehicle.
3.Subtract the combined weight of the
driver and passengers from XXX kg
or XXX lbs.
4.The resulting figure equals the
available amount of cargo and
luggage load capacity. For example, if the "XXX" amount equals 1400 lbs.
and there will be five 150 lb
passengers in your vehicle, the
amount of available cargo and
luggage load capacity is 650 lbs.
(1400-750 (5 x 150) = 650 lbs.)
5.Determine the combined weight of
luggage and cargo being loaded on
the vehicle. That weight may not
safely exceed the available cargo and
luggage load capacity calculated in
Step 4.
6.If your vehicle will be towing a
trailer, load from your trailer will be
transferred to your vehicle. Consult
this manual to determine how this
reduces the available cargo and
luggage load capacity of your
vehicle.”
See Trailer Towing 0293 for important
information on towing a trailer, towing
safety rules, and trailering tips.
Example 1
1. Vehicle Capacity Weight for Example 1
= (453 kg) (1,000 lb)
2. Subtract Occupant Weight @ 68 kg (150 lb) × 2 = 136 kg (300 lb)
3. Available Occupant and Cargo Weight = 317 kg (700 lb)
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228 Driving and Operating
cargo load should not exceed the truck's
cargo weight rating, and the camper's
center of gravity (1) should fall within
the truck's recommended center of
gravity zone (2) when installed.
Any accessories or other equipment
that are added to the vehicle must be
weighed. Then, subtract this extra
weight from the CWR. This extra weight
may shorten the center of gravity zone
of the vehicle.
If the slide-in camper and its load
weighs less than the CWR, the center of
gravity zone for the vehicle may be
larger.
Secure loose items to prevent weight
shifts that could affect the balance of
the vehicle. When the truck-camper is
loaded, drive to a scale and weigh on
the front and on the rear wheels
separately to determine axle loads.
Individual axle loads should not exceed
either of the gross axle weight ratings
(GAWR). The total axle loads should not
exceed the vehicle's gross vehicle
weight rating (GVWR). These ratings aregiven on the Certification/Tire label
attached to the B-pillar. See
“Certification/Tire Label”
underVehicle
Load Limits 0222. If weight ratings are
exceeded, move or remove items to
bring all weights below the ratings.
See your dealer for more information
on curb weights, cargo weights, Cargo
Weight Rating, and the correct center of
gravity zone.
Starting and Operating
New Vehicle Break-In
Caution
The vehicle does not need an elaborate
break-in. But it will perform better in the
long run if you follow these guidelines:
.Keep the vehicle speed at 88 km/h
(55 mph) or less for the first 805 km
(500 mi).
(Continued)
Caution (Continued)
.Do not drive at any one constant
speed, fast or slow, for the first
805 km (500 mi). Do not make
full-throttle starts. Avoid downshifting
to brake or slow the vehicle.
.Avoid making hard stops for the first
322 km (200 mi) or so. During this
time the new brake linings are not yet
broken in. Hard stops with new linings
can mean premature wear and earlier
replacement. Follow this breaking-in
guideline every time you get new
brake linings.
.Do not tow a trailer during break-in.
See Trailer Towing 0293 for the
trailer towing capabilities of the
vehicle and more information.
Following break-in, engine speed and load
can be gradually increased.
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GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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236 Driving and Operating
Retained Accessory Power (RAP)
When the ignition is turned from on to off,
the following features (if equipped) will
continue to function for up to 10 minutes,
or until the driver door is opened. These
features will also work when the ignition is
in RUN or ACC/ACCESSORY:
.Infotainment System
.Power Windows (during RAP this
functionality will be lost when any door
is opened)
.Sunroof (during RAP this functionality will
be lost when any door is opened)
.Auxiliary Power Outlet
.Audio System
.OnStar System
Shifting Into Park
{Warning
It can be dangerous to get out of the
vehicle if the shift lever is not fully in
P (Park) with the parking brake firmly set.
The vehicle can roll. If you have left the
engine running, the vehicle can move
suddenly. You or others could be injured.(Continued)
Warning (Continued)
To be sure the vehicle will not move,
even when you are on fairly level ground,
use the steps that follow. With
four-wheel drive, if the transfer case is in
N (Neutral), the vehicle will be free to
roll, even if the shift lever is in P (Park).
Be sure the transfer case is in a drive
gear. If towing a trailer, seeDriving
Characteristics and Towing Tips 0288.
1. Hold the brake pedal down, then set the parking brake. See Electric Parking Brake
0 247.
2. Move the shift lever into the P (Park) position by pulling the shift lever toward
you and moving it up as far as it will go.
3. Be sure the transfer case (if equipped) is in a drive gear –not in N (Neutral).
4. Turn the ignition off. For Key Access, push the ignition key in, towards the
steering column and then turn the
ignition off.
5. For Key Access, remove the key and take it with you. If you can leave the vehicle
with the ignition key in your hand, the
vehicle is in P (Park). For Keyless Access, take the Remote
Keyless Entry (RKE) transmitter with you.Leaving the Vehicle with the Engine
Running
{Warning
It can be dangerous to leave the vehicle
with the engine running. The vehicle
could move suddenly if the shift lever is
not fully in P (Park) with the parking
brake firmly set.
If you have four-wheel drive and the
transfer case is in N (Neutral), the vehicle
will be free to roll, even if the shift lever
is in P (Park). So be sure the transfer case
is in a drive gear
–not in N (Neutral).
And, if you leave the vehicle with the
engine running, it could overheat and
even catch fire. You or others could be
injured. Do not leave the vehicle with the
engine running unless you have to.
If you have to leave the vehicle with the
engine running, be sure the vehicle is in
P (Park) and the parking brake is firmly set
before you leave it. After moving the shift
lever into P (Park), hold the regular brake
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GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Driving and Operating 239
If parking on a hill and pulling a trailer, see
Driving Characteristics and Towing Tips
0288.
Automatic Transmission
If equipped, there is an electronic shift lever
position indicator within the instrument
cluster. This display comes on when the
ignition is in ACC/ACCESSORY, on or
service mode.
There are several different positions for the
shift lever.
See Driver Mode Control 0251 and “Range
Selection Mode” underManual Mode 0241.
P : This position locks the rear wheels. Use
P (Park) when starting the engine because
the vehicle cannot move easily. When parked on a hill, especially when the
vehicle has a heavy load, you might notice
an increase in the effort to shift out of
P (Park). See
“Torque Lock” underShifting
Into Park 0236.
{Warning
It is dangerous to get out of the vehicle
if the shift lever is not fully in P (Park)
with the parking brake firmly set. The
vehicle can roll.
Do not leave the vehicle when the engine
is running. If you have left the engine
running, the vehicle can move suddenly.
You or others could be injured. To be
sure the vehicle will not move, even
when you are on fairly level ground,
always set the parking brake and move
the shift lever to P (Park). See Shifting
Into Park 0236 and
Driving Characteristics and Towing Tips
0 288.
{Warning
If equipped with four-wheel drive, the
vehicle will be free to roll if the transfer
case is in N (Neutral), even when the shift
lever is in P (Park). You or someone else
could be seriously injured. Be sure the
transfer case is in a drive gear —2
m, 4m,
or 4
n— or set the parking brake before
placing the transfer case in N (Neutral).
See Four-Wheel Drive 0242.
R : Use this gear to back up.
Caution
Shifting to R (Reverse) while the vehicle is
moving forward could damage the
transmission. The repairs would not be
covered by the vehicle warranty. Shift to
R (Reverse) only after the vehicle is
stopped.
To rock the vehicle back and forth to get
out of snow, ice, or sand without damaging
the transmission, see If the Vehicle Is Stuck
0 221.
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GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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240 Driving and Operating
N :In this position, the engine does not
connect with the wheels. To restart the
engine when the vehicle is already moving,
use N (Neutral) only.
Also, use N (Neutral) when the vehicle is
being towed.
{Warning
Shifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is firmly on
the brake pedal, the vehicle could move
very rapidly. You could lose control and
hit people or objects. Do not shift into a
drive gear while the engine is running at
high speed.
Caution
Shifting out of P (Park) or N (Neutral) with
the engine running at high speed may
damage the transmission. The repairs
would not be covered by the vehicle
warranty. Be sure the engine is not
running at high speed when shifting the
vehicle.
Caution
A transmission hot message may display
if the automatic transmission fluid is too
hot. Driving under this condition can
damage the vehicle. Stop and idle the
engine to cool the automatic
transmission fluid. This message clears
when the transmission fluid has cooled
sufficiently.
D : This position is for normal driving.
It provides the best fuel economy. If more
power is needed for passing, press the
accelerator pedal down.
.When going less than about 55 km/h (35
mph), push the accelerator pedal about
halfway down.
.When going about 55 km/h (35 mph) or
more, push the accelerator all the
way down.
By doing this, the vehicle shifts down to
the next gear and has more power.
Use D (Drive) and Tow/Haul Mode when
towing a trailer, carrying a heavy load,
driving on steep hills, or driving off-road.
Shift the transmission to a lower gear if the
transmission shifts too often. Downshifting the transmission in slippery
road conditions could result in skidding. See
“Skidding”
underLoss of Control 0215.
The vehicle has a shift stabilization feature
that adjusts the transmission shifting to the
current driving conditions in order to reduce
rapid upshifts and downshifts. This shift
stabilization feature is designed to
determine, before making an upshift, if the
engine is able to maintain vehicle speed by
analyzing things such as vehicle speed,
throttle position, and vehicle load. If the
shift stabilization feature determines that a
current vehicle speed cannot be maintained,
the transmission does not upshift and
instead holds the current gear. In some
cases, this could appear to be a delayed
shift, however the transmission is operating
normally.
The transmission uses adaptive shift
controls. The adaptive shift control process
continually compares key shift parameters
to pre-programmed ideal shifts stored in the
transmission’s computer. The transmission
constantly makes adjustments to improve
vehicle performance according to how the
vehicle is being used, such as with a heavy
load or when the temperature changes.
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Driving and Operating 241
During this adaptive shift control process,
shifting might feel different as the
transmission determines the best settings.
When temperatures are very cold, the
transmission's gear shifting could be delayed
providing more stable shifts until the engine
warms up. Shifts could be more noticeable
with a cold transmission. This difference in
shifting is normal.
If equipped with the 2.7L L4 engine, engine
speeds may be increased while driving at
highway speeds while the engine is still
warming up.
L :This position allows selection of a range
of gears appropriate for current driving
conditions. If equipped, see “Range Selection
Mode” underManual Mode 0241.
Caution
Spinning the tires or holding the vehicle
in one place on a hill using only the
accelerator pedal may damage the
transmission. The repair will not be
covered by the vehicle warranty. If the
vehicle is stuck, do not spin the tires.
When stopping on a hill, use the brakes
to hold the vehicle in place.
Manual Mode
Electronic Range Select (ERS)
Caution
Driving with the engine at a high rpm
without upshifting while using Manual
Mode, could damage the vehicle. Always
upshift when necessary while using
Manual Mode.
Electronic Range Select (ERS), or Manual
Mode, allows for the selection of the range
of gear positions. Use this mode when
driving downhill or towing a trailer to limit
the top gear and vehicle speed. The shift
position indicator within the Driver
Information Center (DIC) will display a
number next to the L indicating the highest
available gear. To enter Electronic Range Select or
Manual Mode:
1. With the vehicle in D (Drive), pull back on the shift lever to activate L (Low). The
L in the shift pattern will illuminate in
red, and the D will switch to white.
2. Tap the left steering wheel control to reduce the highest gear available, or the
right control to increase the highest gear
available.
3. To exit, pull back on the shift lever a second time. The D in the shift pattern
will illuminate in red, and the L will
switch to white.
When shifting to L (Low), the transmission
will shift to a preset lower gear range. For
this preset range, the highest gear available
will be displayed next to the L in the DIC.
All gears below that number are available to
use. For example, when 4 (Fourth) is shown
next to the L, 1 (First) through 4 (Fourth)
gears are shifted automatically. To shift to 5
(Fifth) gear, tap the right steering wheel
control or shift into D (Drive).
L (Low) will prevent shifting to a lower gear
range if the engine speed is too high. If the
vehicle speed is not reduced within the time
allowed, the lower gear range shift will not