
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
440 Vehicle Care
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
(Continued)
Caution (Continued)
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(Continued)
Caution (Continued)
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Vehicle Care 441
{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 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 0289. 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. Turn the engine off.
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. With a foot on the brake pedal, release the parking brake.
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, then shift the transmission to
P (Park), and move the ignition
key to OFF.
3. Connect the battery.
4. Apply the brake pedal.
5. Turn the ignition to ON/RUN with the engine off. Shift the
transfer case out of N (Neutral)
to Two-Wheel Drive High. See
“Shifting out of N (Neutral)”
under Four-Wheel Drive 0289.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
442 Vehicle Care
See your dealer if the transfer
case cannot be shifted 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 0 °C (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
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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Vehicle Care 443
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 0289 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.
2. Set the parking brake. See Parking Brake 0297.
3. Put the transmission in P (Park).
4. Secure the vehicle to the dolly following the manufacturer's
instructions.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
444 Vehicle Care
5. Use a clamping devicedesigned 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 0297.
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
N (Neutral)” underFour-Wheel
Drive 0289 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 0464.
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
products can be obtained from
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
448 Vehicle Care
Caution (Continued)
or tires. When applying a tire
dressing, always wipe off any
overspray from all painted
surfaces on the vehicle.
Wheels and Trim—Aluminum
or Chrome
Use a soft, clean cloth with mild
soap and water to clean the wheels.
After rinsing thoroughly with clean
water, dry with a soft, clean towel.
A wax may then be applied.
Caution
Chrome wheels and other chrome
trim may be damaged if the
vehicle is not washed after driving
on roads that have been sprayed
with magnesium, calcium,
or sodium chloride. These
chlorides are used on roads for
conditions such as ice and dust.
Always wash the chrome with
soap and water after exposure.
Caution
To avoid surface damage, do not
use strong soaps, chemicals,
abrasive polishes, cleaners,
brushes, or cleaners that contain
acid on aluminum or
chrome-plated wheels. Use only
approved cleaners. Also, never
drive a vehicle with aluminum or
chrome-plated wheels through an
automatic car wash that uses
silicone carbide tire cleaning
brushes. Damage could occur
and the repairs would not be
covered by the vehicle warranty.
Brake System
Visually inspect brake lines and
hoses for proper hook-up, binding,
leaks, cracks, chafing, etc. Inspect
disc brake pads for wear and rotors
for surface condition. Inspect drum
brake linings/shoes for wear or
cracks. Inspect all other brake parts.
Steering, Suspension, and
Chassis Components
Visually inspect steering,
suspension, and chassis
components for damaged, loose,
or missing parts or signs of wear at
least once a year.
Inspect power steering for proper
attachment, connections, binding,
leaks, cracks, chafing, etc.
Visually check constant velocity joint
boots and axle seals for leaks.
1500 Series vehicles, at least every
other oil change lubricate the outer
tie rod ends.
2500/3500 Series vehicles, at least
every other engine oil change
lubricate the upper and lower
control arm ball joints. Control arm
ball joints on 1500 series vehicles
are maintenance-free.
2500/3500 Series vehicles equipped
with steering linkage, at least every
other engine oil change lubricate the
tie rod ball joints, idler arm pivot
shaft bearings, idler arm socket, and
pitman arm socket.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Service and Maintenance 461
(2)Visually check all fuel and vapor
lines and hoses for proper
attachment, connection, routing, and
condition.
(3) Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
(4) Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water
can overcome the seals and
contaminate the transfer case fluid.
Contaminated fluid will decrease the
life of the transfer case and/or axles
and should be replaced.
(5) Or every five years, whichever
comes first. See Cooling System
0 372.
(6) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage;
replace, if needed.
(7) Replace brake fluid every five
years. See Brake Fluid 0381.Special Application
Services
.
Vehicles with Dual Wheels:
Check dual wheel nut torque at
160, 1 600, and 10 000 km (100,
1,000, and 6,000 mi) of driving.
Repeat this service whenever a
tire/wheel is serviced or
removed.
. Severe Commercial Use
Vehicles Only: Lubricate chassis
components every oil change.
. Have underbody flushing service
performed. See “Underbody
Maintenance” inExterior Care
0 444.
Additional
Maintenance and Care
Your vehicle is an important
investment and caring for it properly
may help to avoid future costly
repairs. To maintain vehicle
performance, additional
maintenance services may be
required.
It is recommended that your dealer
perform these services —their
trained dealer technicians know
your vehicle best. Your dealer can
also perform a thorough
assessment with a multi-point
inspection to recommend when your
vehicle may need attention.
The following list is intended to
explain the services and conditions
to look for that may indicate
services are required.
Battery
The 12-volt battery supplies power
to start the engine and operate any
additional electrical accessories.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
462 Service and Maintenance
.To avoid break-down or failure to
start the vehicle, maintain a
battery with full cranking power.
. Trained dealer technicians have
the diagnostic equipment to test
the battery and ensure that the
connections and cables are
corrosion-free.
Belts
. Belts may need replacing if they
squeak or show signs of
cracking or splitting.
. Trained dealer technicians have
access to tools and equipment
to inspect the belts and
recommend adjustment or
replacement when necessary.
Brakes
Brakes stop the vehicle and are
crucial to safe driving.
. Signs of brake wear may include
chirping, grinding, or squealing
noises, or difficulty stopping. .
Trained dealer technicians have
access to tools and equipment
to inspect the brakes and
recommend quality parts
engineered for the vehicle.
Fluids
Proper fluid levels and approved
fluids protect the vehicle’s systems
and components. See
Recommended Fluids and
Lubricants 0464 for GM approved
fluids.
. Engine oil and windshield
washer fluid levels should be
checked at every fuel fill.
. Instrument cluster lights may
come on to indicate that fluids
may be low and need to be
filled.
Hoses
Hoses transport fluids and should
be regularly inspected to ensure
that there are no cracks or leaks.
With a multi-point inspection, your
dealer can inspect the hoses and
advise if replacement is needed. Lamps
Properly working headlamps,
taillamps, and brake lamps are
important to see and be seen on
the road.
.
Signs that the headlamps need
attention include dimming, failure
to light, cracking, or damage.
The brake lamps need to be
checked periodically to ensure
that they light when braking.
. With a multi-point inspection,
your dealer can check the lamps
and note any concerns.
Shocks and Struts
Shocks and struts help aid in control
for a smoother ride.
. Signs of wear may include
steering wheel vibration, bounce/
sway while braking, longer
stopping distance, or uneven
tire wear.
. As part of the multi-point
inspection, trained dealer
technicians can visually inspect
the shocks and struts for signs