2023 GMC SIERRA VEHICLE

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/18/22
366 Vehicle Care
9. Make sure the tire is stored securely.Push, pull, and then try to turn the tire.
If the tire moves, use the wheel wrench
to tighten the cable.
If equipped with a spare tire cable,
reattach the clip to the frame
attachment bracket. Note that there may
be slack in the cable.
Repeat this tightness check procedure
when checking the spare tire pressure
according to the scheduled maintenance
information or any time the spare tire is
handled due to service of other
components.
Correctly Stored
Incorrectly Stored
10. Reinstall the spare tire lock, if the vehicle has one.
Return the jack and tools to their original
location in the vehicle. See “Removing the
Spare Tire and Tools.”

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/18/22
Vehicle Care 367
Full-Size Spare Tire
If this vehicle came with a full-size spare
tire, it was fully inflated when new,
however, it can lose air over time. Check the
inflation pressure regularly. SeeTire Pressure
0 342 and
Vehicle Load Limits 0215 for information
regarding proper tire inflation and loading
the vehicle. For instructions on how to
remove, install, or store a spare tire, see Tire
Changing 0357.
After installing the spare tire on the vehicle,
stop as soon as possible and check that the
spare is correctly inflated. The spare tire is
made to perform well at speeds up to
112 km/h (70 MPH) at the recommended
inflation pressure, so you can finish
your trip.
Have the damaged or flat road tire repaired
or replaced and installed back onto the
vehicle as soon as possible so the spare tire
will be available in case it is needed again.
Do not mix tires and wheels of different
sizes, because they will not fit. Keep the
spare tire and its wheel together.
Caution
If the vehicle has four-wheel drive and a
different size spare tire is installed, do
not drive in four-wheel drive until the flat
tire is repaired and/or replaced. The
vehicle could be damaged and the repairs
would not be covered by the warranty.
Never use four-wheel drive when a
different size spare tire is installed on the
vehicle.
The vehicle may have a different size spare
tire than the road tires originally installed
on the vehicle. This spare tire was developed
for use on this vehicle, so it is all right to
drive on it. If the vehicle has four-wheel
drive and a different size spare tire is
installed, drive only in two-wheel drive.
If the vehicle has a spare tire that does not
match the vehicle’s original road tires and
wheels, in size and type, do not include the
spare in the tire rotation.
Jump Starting
Jump Starting - North America
For more information about the vehicle
battery, see Battery - North America 0319. If the vehicle's battery (or batteries) has run
down, you may want to use another vehicle
and some jumper cables to start your
vehicle. Be sure to use the following steps
to do it safely.
{Warning
WARNING:
Battery posts, terminals and
related accessories can expose you to
chemicals including lead and lead
compounds, which are known to the
State of California to cause cancer and
birth defects or other reproductive harm.
Wash hands after handling. For more
information go to
www.P65Warnings.ca.gov.
See California Proposition 65 Warning 01.
{Warning
Batteries can hurt you. They can be
dangerous because:
.They contain acid that can burn you.
.They contain gas that can explode or
ignite.
.They contain enough electricity to
burn you.
(Continued)

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/18/22
368 Vehicle Care
Warning (Continued)
If you do not follow these steps exactly,
some or all of these things can hurt you.
Caution
Ignoring these steps could result in costly
damage to the vehicle that would not be
covered by the vehicle warranty. Trying
to start the vehicle by pushing or pulling
it will not work, and it could damage the
vehicle.
Caution
If the jumper cables are connected or
removed in the wrong order, electrical
shorting may occur and damage the
vehicle. The repairs would not be covered
by the vehicle warranty. Always connect
and remove the jumper cables in the
correct order, making sure that the cables
do not touch each other or other metal.
Connection Points and Sequence
1. Discharged Battery Positive (+)Terminal
2. Good Battery Positive (+) Terminal
3. Good Battery Negative (−) Terminal
4. Discharged Battery Negative Grounding (−) Terminal
The good battery positive (+) terminal and
the good battery negative (–) terminal are
on the battery of the vehicle providing the
jump start.
The discharged battery positive (+) terminal
and the discharged battery negative (–)
grounding point are on the passenger side
of the vehicle. The discharged battery positive (+) terminal
is under a cover. Open the cover to expose
the terminal.
1. Check the other vehicle. It must have a 12-volt battery with a negative ground
system.
Caution
If the other vehicle does not have a
12-volt system with a negative ground,
both vehicles can be damaged. Only use
a vehicle that has a 12-volt system with a
negative ground for jump starting.
2. If you have a vehicle with a diesel engine with two batteries, you should
know before you begin that, especially in
cold weather, you may not be able to
get enough power from a single battery
in another vehicle to start your diesel
engine. If your vehicle has more than
one battery, using the battery that is
closer to the starter will reduce electrical
resistance. This is located on the
passenger side, in the rear of the engine
compartment.
3. Get the vehicles close enough so the jumper cables can reach, but be sure the
vehicles are not touching each other.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/18/22
Vehicle Care 369
If they are, it could cause an unwanted
ground connection. You would not be
able to start your vehicle, and the bad
grounding could damage the electrical
systems.
To avoid the possibility of the vehicles
rolling, set the parking brake firmly on
both vehicles involved in the jump start
procedure. Put the automatic
transmission in P (Park) before setting
the parking brake. If you have a
four-wheel-drive vehicle, be sure the
transfer case is in a drive gear, not in
N (Neutral).
Caution
If any accessories are left on or plugged
in during the jump starting procedure,
they could be damaged. The repairs
would not be covered by the vehicle
warranty. Whenever possible, turn off or
unplug all accessories on either vehicle
when jump starting.
4. Turn the ignition off on both vehicles. Unplug unnecessary accessories plugged
into the accessory power outlets. Turn
off the radio and all the lamps that are not needed. This will avoid sparks and
help save both batteries. And it could
save the radio!
5. Open the hood on the other vehicle and locate the positive (+) and negative (−)
terminal locations on that vehicle.
{Warning
An electric fan can start up even when
the engine is not running and can injure
you. Keep hands, clothing, and tools
away from any underhood electric fan.
{Warning
Using a match near a battery can cause
battery gas to explode. People have been
hurt doing this, and some have been
blinded. Use a flashlight if you need
more light.
Battery fluid contains acid that can burn
you. Do not get it on you. If you
accidentally get it in your eyes or on
your skin, flush the place with water and
get medical help immediately.
{Warning
Fans or other moving engine parts can
injure you badly. Keep your hands away
from moving parts once the engine is
running.
6. Check that the jumper cables do not have loose or missing insulation. If they
do, you could get a shock. The vehicles
could be damaged too.
Before you connect the cables, here are
some basic things you should know.
Positive (+) will go to positive (+) or to a
remote positive (+) terminal if the
vehicle has one. Negative (–) will go to a
heavy, unpainted metal engine part or to
a remote negative (–) terminal if the
vehicle has one.
Do not connect positive (+) to negative
(–) or you will get a short that would
damage the battery and maybe other
parts too. And do not connect the
negative (–) cable to the negative (–)
terminal on the dead battery because
this can cause sparks.
7. Connect one end of the red positive (+) cable to the discharged battery
positive (+) terminal.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/18/22
370 Vehicle Care
8. Do not let the other end touch metal.Connect it to the good battery
positive (+) terminal. Use a remote
positive (+) terminal if the vehicle
has one.
9. Connect one end of the black negative (–) cable to the good battery negative
(–) terminal. Use a remote negative (–)
terminal if the vehicle has one.
Do not let the other end touch anything
until the next step.
10. Connect the other end of the negative (–) cable to the discharged battery
negative (–) grounding point.
11. Start the vehicle with the good battery and run the engine for a while.
12. Try to start the vehicle that had the dead battery. If it will not start after a
few tries, it probably needs service.
Jumper Cable Removal
Reverse the sequence exactly when
removing the jumper cables.
After starting the disabled vehicle and
removing the jumper cables, allow it to idle
for several minutes.Towing the Vehicle
Transporting a Disabled Vehicle
Caution
Incorrectly transporting a disabled vehicle
may cause damage to the vehicle. Use
proper tire straps to secure the vehicle to
the flatbed tow truck. Do not strap or
hook to any frame, underbody,
or suspension component not specified
below. Do not move vehicles with drive
axle tires on the ground. Damage is not
covered by the vehicle warranty.
Caution
The vehicle may be equipped with an
electric parking brake and/or a
mechanical transmission range select
shifter. In the event of a loss of 12-volt
battery power, the electric parking brake
cannot be released, and the vehicle
cannot be shifted to N (Neutral). Tire
skates or dollies must be used under the
non-rolling tires to prevent damage while
(Continued)
Caution (Continued)
loading/unloading the vehicle. Dragging
the vehicle will cause damage not
covered by the vehicle warranty.
Caution
The vehicle may be equipped with a tow
eye. Improper use of the tow eye may
cause damage to the vehicle and is not
covered by the vehicle warranty.
If equipped, use the tow eye to load the
vehicle onto a flatbed tow truck from a
flat road surface, or to move the vehicle
a very short distance at a walking pace.
The tow eye is not designed for off-road
recovery. The vehicle must be in
N (Neutral) with the electric parking
brake released when using the tow eye.
Contact a professional towing service if the
disabled vehicle must be transported. GM
recommends a flatbed tow truck to
transport a disabled vehicle. Use ramps to
help reduce approach angles, if necessary.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/18/22
Vehicle Care 371
If equipped, a tow eye may be located near
the spare tire or emergency jack. Do not use
the tow eye to pull the vehicle from the
snow, mud, sand, or ditch. Tow eye threads
may have right or left-hand threads. Use
caution when installing or removing the
tow eye.
The vehicle must be in N (Neutral) and the
electric parking brake must be released
when loading the vehicle onto a flatbed tow
truck.
.If the 12-volt battery is dead and/or
electric parking brake is not released, the
vehicle will not move. Try to jump start
the vehicle with a known good 12-volt
battery, shift the car into N (Neutral), and
release the electric parking brake. Refer to
Jump Starting - North America0367.
.If unsuccessful, the vehicle will not move.
Tire skates or dollies must be used under
the non-rolling tires to prevent vehicle
damage.
Front Attachment Points
The vehicle is equipped with specific
attachment points to be used to pull the
vehicle onto a flatbed car carrier from a flat
road surface. Do not use these attachment
points to pull the vehicle from snow, mud
or sand.
Recreational Vehicle Towing
Recreational vehicle towing means towing
the vehicle behind another vehicle, such as a
motor home. The two most common types
of recreational vehicle towing are dinghy
and dolly towing. Dinghy towing is towing
the vehicle with all four wheels on the ground. Dolly towing is towing the vehicle
with two wheels on the ground and two
wheels on a dolly.
Here are some important things to consider
before recreational vehicle towing:
.Before towing the vehicle, become
familiar with the local laws that apply to
recreational vehicle towing. These laws
may vary by region.
.The towing capacity of the towing
vehicle. Read the tow vehicle
manufacturer's recommendations.
.How far the vehicle can be towed. Some
vehicles have restrictions on how far and
how long the vehicle can be towed.
.Whether the vehicle has the proper
towing equipment. See your dealer or
trailering professional for additional
advice and equipment recommendations.
.Whether the vehicle is ready to be towed.
Just as preparing the vehicle for a long
trip, make sure the vehicle is prepared to
be towed.
Follow the tow vehicle manufacturer’s
instructions. See your dealer or trailering
professional for additional advice and
equipment recommendations.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/18/22
372 Vehicle Care
Caution
Use of a shield mounted in front of the
vehicle grille could restrict airflow and
cause damage to the transmission. The
repairs would not be covered by the
vehicle warranty. If using a shield, only
use one that attaches to the towing
vehicle.
Dinghy Towing (Two-Wheel-Drive
Vehicles and Vehicles with a
Single-Speed Transfer Case)
Caution
If a vehicle with two-wheel drive or a
single-speed transfer case is towed with
all four wheels on the ground, the
drivetrain components could be damaged.
The repairs would not be covered by the
vehicle warranty.
Two-wheel-drive vehicles and vehicles with a
single-speed transfer case should not be
towed with all four wheels on the ground.
Dinghy Towing (Vehicles with a
Two-Speed Transfer Case)
Only dinghy tow four-wheel-drive vehicles
with a two-speed transfer case that have an
N (Neutral) and a 4
n(Four-Wheel Drive
Low) setting.
{Warning
Shifting a four-wheel-drive vehicle's
transfer case into N (Neutral) can allow
the vehicle to move even if the
transmission is in P (Park). You or others
could be injured. Set the parking brake
and use wheel blocks before shifting the
transfer case to N (Neutral).
To dinghy tow: 1. Position the vehicle being towed behind the tow vehicle, facing forward and on a
level surface.
2. Securely attach the vehicle being towed to the tow vehicle.
3. Apply the parking brake and start the engine.
4. Shift the transfer case to N (Neutral). See “Shifting into N (Neutral)” under
Four-Wheel Drive 0234.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/18/22
Vehicle Care 373
5. With the engine running, release theparking brake and verify that the
transfer case is in N (Neutral) by shifting
the transmission to D (Drive) and then to
R (Reverse). There should be no
movement while shifting the
transmission.
6. Shift the transmission to D (Drive).
7. If equipped with an ignition key, turn the ignition to ACC/ACCESSORY.
If equipped with Keyless Access, turn the
engine off. Disregard the Shift to P (Park)
DIC message. See Ignition Positions (Key
Access) 0221 or
Ignition Positions (Keyless Access) 0223.
{Warning
To avoid death, serious injury,
or property damage, before dinghy
towing the vehicle, always disconnect and
secure the negative battery cable and
cover the negative battery post and cable
with a non-conductive material. If the
battery is left connected or the battery
cable contacts the post, the Electric
Parking Brake may activate during
towing, which could cause a crash. 8. Disconnect the negative (–) battery
cable. See “Negative Battery Cable
Disconnection” inBattery - North
America 0319.
9. Shift the transmission to P (Park).
Caution
If the steering column is locked, vehicle
damage may occur.
10. Move the steering wheel to make sure the steering column is unlocked.
11. If the vehicle has an ignition key, keep it in the towed vehicle in ACC/ACCESSORY
to prevent the steering column from
locking. If the vehicle is equipped with
Keyless Access, keep the RKE transmitter
outside of the vehicle and manually lock
the doors. Access the vehicle by using
the key in the door lock. See Door Locks
0 23.
Disconnecting the Towed Vehicle
Before disconnecting from the tow vehicle: 1. Park on a level surface. Secure the vehicle with wheel blocks.
2. Re-connect the negative (–) battery. See Battery - North America 0319. 3. Turn on the ignition with the engine off.
For vehicles with a key, turn the ignition
to ON/RUN with the engine off. If the
vehicle is equipped with Keyless Access,
with your foot off the brake pedal, press
and hold ENGINE START/STOP for
five seconds until the green light comes
on in the button. See Ignition Positions
(Key Access) 0221 or
Ignition Positions (Keyless Access) 0223.
4. Set the parking brake. See Electric
Parking Brake 0239.
5. Disconnect from the tow vehicle.
6. Shift the transmission to N (Neutral).
7. Shift the transfer case to 2
m(Two-Wheel
Drive High). When the shift to 2
m
(Two-Wheel Drive High) is complete, the
light in the instrument cluster will stop
flashing and stay lit. See
Four-Wheel-Drive Light 0123.
8. Start the engine. Check that the vehicle is in 2
m(Two-Wheel Drive High) by
starting the engine and shifting the
transmission to D (Drive) and then to
R (Reverse). There should be movement
of the vehicle while shifting.
9. Shift the transmission to P (Park) and turn off the ignition.