2015 GMC SIERRA Owner's Manual

Black plate (90,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-90 Vehicle Care
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.
5.3L and 6.2L
‐ To the metal bracket that is
bolted to the engine and
supports the resonator, on
the vehicle with the dead
battery.6.0L
‐ To the generator bracket, on
the vehicle with the dead
battery.

Black plate (91,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-91
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.
Towing the Vehicle
{Caution
Incorrectly towing a disabled
vehicle may cause damage. The
damage would not be covered by
the vehicle warranty.
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.
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

Black plate (92,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-92 Vehicle Care
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
{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 VehiclesOnly 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.

Black plate (93,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-93
{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 9-40 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.
6. Disconnect the negative battery cable 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.
8. Move the steering wheel to make sure the steering column
is unlocked.
9. Release the parking brake.
10. 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.

Black plate (94,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-94 Vehicle Care
5. Start the engine, then shift thetransfer 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
{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
(Continued)
Caution (Continued)
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.

Black plate (95,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-95
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 9-40 for the
proper procedure. 8. Release the parking brake only
after 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.

Black plate (96,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-96 Vehicle Care
2. Set the parking brake. SeeParking Brake on page 9-47.
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 9-47.
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 9-40 for the proper
procedure.
7. Turn the ignition to LOCK/OFF.
Appearance Care
Exterior Care
Locks
Locks are lubricated at the factory.
Use a de-icing agent only when
absolutely necessary, and have the
locks greased after using. See
Recommended Fluids and
Lubricants on page 11-12.
Washing the Vehicle
To preserve the vehicle's finish,
wash it often and out of direct
sunlight.
{Caution
Do not use petroleum-based,
acidic, or abrasive cleaning
agents as they can damage the
vehicle's paint, metal, or plastic
parts. If damage occurs, it would
not be covered by the vehicle
warranty. Approved cleaning (Continued)

Black plate (97,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-97
Caution (Continued)
products can be obtained from
your dealer. Follow all
manufacturer directions regarding
correct product usage, necessary
safety precautions, and
appropriate disposal of any
vehicle care product.
{Caution
Avoid using high-pressure
washes closer than 30 cm (12 in)
to the surface of the vehicle. Use
of power washers exceeding
8,274 kPa (1,200 psi) can result
in damage or removal of paint
and decals.
This symbol
eis on any
underhood compartment electrical
center that should not be power washed. This could cause damage
that would not be covered by the
vehicle warranty.
If using an automatic car wash,
follow with the car wash
instructions. The windshield wiper
and rear window wiper, if equipped,
must be off. Remove any
accessories that may be damaged
or interfere with the car wash
equipment.
Rinse the vehicle well, before
washing and after, to remove all
cleaning agents completely. If they
are allowed to dry on the surface,
they could stain.
Dry the finish with a soft, clean
chamois or an all-cotton towel to
avoid surface scratches and water
spotting.
Finish Care
Application of aftermarket clearcoat
sealant/wax materials is not
recommended. If painted surfaces
are damaged, see your dealer to
have the damage assessed andrepaired. Foreign materials such as
calcium chloride and other salts, ice
melting agents, road oil and tar, tree
sap, bird droppings, chemicals from
industrial chimneys, etc., can
damage the vehicle's finish if they
remain on painted surfaces. Wash
the vehicle as soon as possible.
If necessary, use non-abrasive
cleaners that are marked safe for
painted surfaces to remove foreign
matter.
Occasional hand waxing or mild
polishing should be done to remove
residue from the paint finish. See
your dealer for approved cleaning
products.
Do not apply waxes or polishes to
uncoated plastic, vinyl, rubber,
decals, simulated wood, or flat paint
as damage can occur.