Page 457 of 539

Black plate (90,1)GMC Sierra Owner Manual (GMNA Localizing-U.S/Canada/Mexico-
7299746) - 2015 - crc - 11/11/13
10-90 Vehicle Care
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.
The positive (+) terminal is under
a red plastic cover at the positive
battery post. To uncover the
positive (+) terminal, open the
red plastic cover.
For more information on the
location of the remote
positive (+) and remote negative
(−) terminals, see Engine
Compartment Overview on
page 10-5.{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 an open flame 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.
Be sure the battery has enough
water. You do not need to add
water to the battery installed in
your new vehicle. But if a battery
has filler caps, be sure the right
amount of fluid is there. If it is low,
(Continued)
Warning (Continued)
add water to take care of that
first. If you do not, explosive gas
could be present.
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.
Page 458 of 539

Black plate (91,1)GMC Sierra Owner Manual (GMNA Localizing-U.S/Canada/Mexico-
7299746) - 2015 - crc - 11/11/13
Vehicle Care 10-91
6. Check that the jumper cables donot 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.
5.3L Shown, 4.3L, 6.0L, 6.2L and
6.6L Similar
7. Connect the red positive (+) cable to the positive (+) terminal
of the vehicle with the dead
battery.
8. Do not let the other end touch metal. Connect it to the
positive (+) terminal of the good
battery. Use a remote
positive (+) terminal if the
vehicle has one. 9. Connect the black negative (−)
cable to the negative (−) terminal
of the good battery. 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.
4.3L Shown, 5.3L and 6.2L Similar
‐To the metal bracket that is
bolted to the engine and
supports the resonator, on
the vehicle with the dead
battery.
Page 459 of 539
Black plate (92,1)GMC Sierra Owner Manual (GMNA Localizing-U.S/Canada/Mexico-
7299746) - 2015 - crc - 11/11/13
10-92 Vehicle Care
6.0L
‐ To the generator bracket, on
the vehicle with the dead
battery.6.6L
‐ To the negative (−) post on
the auxiliary battery, on the
vehicle with the dead battery.
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.
{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.
Jumper Cable Removal
Reverse the sequence exactly when
removing the jumper cables.
Page 460 of 539

Black plate (93,1)GMC Sierra Owner Manual (GMNA Localizing-U.S/Canada/Mexico-
7299746) - 2015 - crc - 11/11/13
Vehicle Care 10-93
Towing the Vehicle
{Caution
Incorrectly towing a disabled
vehicle may cause damage. The
damage would not be covered by
the vehicle warranty. Do not lash
or hook to the chassis
components—including the front
and rear subframes, suspension
control arms, and links —during
towing and recovery of a disabled
vehicle, or when securing the
vehicle. Use the proper nylon
strap harnesses around the tires
to secure the vehicle.
Have the vehicle towed on a flatbed
car carrier. A wheel lift tow truck
could damage the vehicle.
Consult your dealer or a
professional towing service if the
disabled vehicle must be towed. To tow the vehicle behind another
vehicle for recreational purposes,
such as behind a motor home, see
“Recreational Vehicle Towing”
following.
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.
Follow the tow vehicle
manufacturer
’s instructions. See
your dealer or trailering professional
for additional advice and equipment
recommendations.
{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
Page 461 of 539

Black plate (94,1)GMC Sierra Owner Manual (GMNA Localizing-U.S/Canada/Mexico-
7299746) - 2015 - crc - 11/11/13
10-94 Vehicle Care
{Caution
If the two-wheel-drive vehicle 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 should not
be towed with all four wheels on the
ground.
Four-Wheel-Drive Vehicles
Only dinghy tow four-wheel-drive
vehicles with a two-speed transfer
case that have an N (Neutral) and a
Four-Wheel Drive Low (4 (
n) setting.
{Warning
Shifting a four-wheel-drive
vehicle's transfer case into
N (Neutral) can cause the vehicle
to roll even if the transmission is
in P (Park). You or others could
be injured. Set the parking brake
before shifting the transfer case
to N (Neutral).
Follow these steps 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)” underFour-Wheel
Drive on page 9-38 for the
proper procedure. Check that
the vehicle is in N (Neutral) by
shifting the transmission to
R (Reverse) and then to D
(Drive). There should be no
movement of the vehicle while
shifting.
5. With the transmission in D (Drive), turn the ignition to ACC/
ACCESSORY.
{Caution
Failure to disconnect the negative
battery cable or to have it contact
the terminals can cause damage
to the vehicle.
Page 462 of 539

Black plate (95,1)GMC Sierra Owner Manual (GMNA Localizing-U.S/Canada/Mexico-
7299746) - 2015 - crc - 11/11/13
Vehicle Care 10-95
6. Disconnect the negative batterycable at the battery and secure
the nut and bolt. Cover the
negative battery post with a
non-conductive material to
prevent any contact with the
negative battery terminal.
7. Shift the transmission to P (Park).
{Caution
If the steering column is locked,
vehicle damage may occur.
9. Move the steering wheel to make sure the steering column
is unlocked.
10. Release the parking brake.
11. Keep the ignition key in the towed vehicle in ACC/
ACCESSORY to prevent the
steering column from locking. Disconnecting the Towed Vehicle
Before disconnecting the towed
vehicle:
1. Park on a level surface.
2. Set the parking brake, shift the
transmission to P (Park), and
move the ignition key to OFF.
3. Connect the battery.
4. Apply the brake pedal.
5. Start the engine, then shift the transfer case out of N (Neutral)
to Two-Wheel Drive High. See
Four-Wheel Drive for directions
on shifting out of N (Neutral).
6. Check that the vehicle is in Two-Wheel Drive High by
shifting the transmission to
R (Reverse) and then to D
(Drive). There should be
movement of the vehicle while
shifting.
7. Shift the transmission to P (Park) and turn off the ignition.
8. Disconnect the vehicle from the tow vehicle. 9. Release the parking brake.
10. Reset any lost presets.
The outside temperature
display will default to 32°F but
will reset with normal usage.
Dolly Towing
Front Towing (Front Wheels Off
the Ground) –Two-Wheel-Drive
Vehicles
Page 463 of 539

Black plate (96,1)GMC Sierra Owner Manual (GMNA Localizing-U.S/Canada/Mexico-
7299746) - 2015 - crc - 11/11/13
10-96 Vehicle Care
{Caution
If a two-wheel-drive vehicle is
towed with the rear wheels on the
ground, the transmission could be
damaged. The repairs would not
be covered by the vehicle
warranty. Never tow the vehicle
with the rear wheels on the
ground.
Two-wheel-drive vehicles should not
be towed with the rear wheels on
the ground. Two-wheel-drive
transmissions have no provisions
for internal lubrication while being
towed.
To dolly tow a two-wheel-drive
vehicle, the vehicle must be towed
with the rear wheels on the dolly.
See “Rear Towing (Rear Wheels Off
the Ground)” later in this section. Front Towing (Front Wheels Off
the Ground)
–Four-Wheel-Drive
Vehicles
To dolly tow a four-wheel-drive
vehicle from the front:
1. Attach the dolly to the tow
vehicle following the dolly
manufacturer's instructions.
2. Drive the front wheels onto the dolly.
3. Shift the transmission to P (Park).
4. Set the parking brake.
{Warning
Shifting a four-wheel-drive
vehicle's transfer case into
N (Neutral) can cause the vehicle
to roll even if the transmission is
in P (Park). You or others could
be injured. Set the parking brake
before shifting the transfer case
to N (Neutral).
5. Use a clamping device designed for towing to ensure that the
front wheels are locked into the
straight position.
6. Secure the vehicle to the dolly following the manufacturer's
instructions.
7. Shift the transfer case to N (Neutral). See “Shifting into
N (Neutral)” underFour-Wheel
Drive on page 9-38 for the
proper procedure.
Page 464 of 539

Black plate (97,1)GMC Sierra Owner Manual (GMNA Localizing-U.S/Canada/Mexico-
7299746) - 2015 - crc - 11/11/13
Vehicle Care 10-97
8. Release the parking brake onlyafter the vehicle being towed is
firmly attached to the tow
vehicle.
9. Turn the ignition to LOCK/OFF.
Rear Towing (Rear Wheels Off
the Ground)
Two-Wheel-Drive Vehicles
To dolly tow a two-wheel-drive
vehicle from the rear:
1. Drive the rear wheels onto the dolly. 2. Set the parking brake. See
Parking Brake on page 9-48.
3. Put the transmission in P (Park).
4. Secure the vehicle to the dolly following the manufacturer's
instructions.
5. Use a clamping device designed for towing to ensure that the
front wheels are locked into the
straight position.
6. Turn the ignition to LOCK/OFF.
Four-Wheel-Drive Vehicles
{Warning
Shifting a four-wheel-drive
vehicle's transfer case into
N (Neutral) can cause the vehicle
to roll even if the transmission is
in P (Park). You or others could
be injured. Set the parking brake
before shifting the transfer case
to N (Neutral). To dolly tow a four-wheel-drive
vehicle from the rear:
1. Drive the rear wheels onto the
dolly.
2. Set the parking brake. See Parking Brake on page 9-48.
3. Put the transmission in P (Park).
4. Secure the vehicle to the dolly following the manufacturer's
instructions.
5. Use a clamping device designed for towing to ensure that the
front wheels are locked into the
straight position.
6. Shift the transfer case to N (Neutral). See “Shifting into
Neutral” underFour-Wheel Drive
on page 9-38 for the proper
procedure.
7. Turn the ignition to LOCK/OFF.