2020 GMC SIERRA DENALI wheel

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
424 Vehicle Care
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 suspension
components. Use the proper
straps around the tires to secure
the vehicle. Do not drag a locked
wheel/tire. Use tire skates or
dollies under any locked wheel/
tire while loading the vehicle. Do
not use a sling type lift to tow the
vehicle. This could damage the
vehicle.
Caution
If the vehicle cannot be shifted
into Neutral (N), do not use the
tow eye to tow the vehicle.
Vehicle damage may occur.GM recommends a flatbed tow truck
to transport a disabled vehicle. Use
ramps to help reduce approach
angles, if necessary. A towed
vehicle should have its drive wheels
off the ground. Contact Roadside
Assistance or a professional towing
service if the disabled vehicle must
be towed.
Front Attachment Points
1500
2500/3500
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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 425
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.
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
426 Vehicle Care
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. Start the engine.
4. Shift the transfer case to N (Neutral). See “Shifting into
N (Neutral)” underFour-Wheel
Drive 0227. 5. With the engine running,
release the parking 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 (Keyless
Access) 0208 or
Ignition Positions (Key Access)
0 210.
{Warning
To avoid death, serious injury,
or property damage, before
dinghy towing the vehicle, always
disconnect and secure the
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 427
Warning (Continued)
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”
in Battery - North America
0 358.
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 026.
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 0358. 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 (Keyless
Access) 0208 or
Ignition Positions (Key Access)
0 210.
4. Set the parking brake. See Electric Parking Brake 0233.
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
0 141.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
428 Vehicle Care
8. Start the engine. Check thatthe 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.
10. Release the parking brake and remove the wheel blocks.
11. Reset any lost presets. The outside temperature
display will default to 0 °C
(32 °F) but will reset with
normal usage.
Dolly TowingCaution
Do not tow this vehicle with two
wheels on the ground, or vehicle
damage could occur. This
damage would not be covered by
the vehicle warranty.
Dolly towing this vehicle is not
allowed with either the front or the
rear tires on the ground for
two-wheel drive or four-wheel drive,
regardless of transfer case.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
430 Vehicle Care
Automatic Car Wash
Caution
Some automatic car washes can
cause damage to the vehicle,
wheels and ground effects.
Automatic car washes are not
recommended, due to lack of
clearance for the undercarriage
and/or wide rear tires and wheels.
Caution
Automatic car washes can cause
damage to the vehicle, wheels,
ground effects, and convertible
top (if equipped).
Do not use automatic car washes
due to lack of clearance for the
undercarriage, wide rear tires,
and wheels.
If using an automatic car wash,
follow with the car wash
instructions. The windshield wiper
and rear window wiper, if equipped, must be turned off. Remove any
accessories that may be damaged
or interfere with the car wash
equipment.
See
Power Assist Steps 034 for
cleaning information.
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 and
repaired. 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.
Caution
Machine compounding or
aggressive polishing on a
basecoat/clearcoat paint finish
may damage it. Use only
non-abrasive waxes and polishes
that are made for a basecoat/
clearcoat paint finish on the
vehicle.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 433
a buildup of vehicle wash/wax
treatments may cause wiper
streaking.
Replace the wiper blades if they are
worn or damaged. Damage can be
caused by extreme dusty
conditions, sand, salt, heat, sun,
snow, and ice.
Weatherstrips
Apply weatherstrip lubricant on
weatherstrips to make them last
longer, seal better, and not stick or
squeak. Lubricate weatherstrips
once a year. Hot, dry climates may
require more frequent application.
Black marks from rubber material on
painted surfaces can be removed by
rubbing with a clean cloth. See
Recommended Fluids and
Lubricants0452.
Tires
Use a stiff brush with tire cleaner to
clean the tires.
Caution
Using petroleum-based tire
dressing products on the vehicle
may damage the paint finish and/
or tires. When applying a tire
dressing, always wipe off any
overspray from all painted
surfaces on the vehicle.
Wheels and Wheel Trim
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 chrome
wheel trim may be damaged if the
vehicle is not washed after driving
on roads that have been sprayed
with magnesium chloride or
calcium chloride. These are used
on roads for conditions such as
(Continued)
Caution (Continued)
dust and ice. Always wash the
chrome with soap and water after
exposure.
Caution
To avoid surface damage on
wheels and wheel trim, do not
use strong soaps, chemicals,
abrasive polishes, cleaners,
or brushes. Use only GM
approved cleaners. Do not drive
the vehicle through an automatic
car wash that uses silicon carbide
tire/wheel 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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
448 Service and Maintenance
Footnotes—Maintenance
Schedule Additional Required
Services - Severe
(1) Or every two years, whichever
comes first. More frequent
replacement may be needed if the
vehicle is driven in areas with heavy
traffic, poor air quality, areas with
high dust levels or are sensitive to
environmental allergens. Filter
replacement may also be needed if
you notice reduced airflow, windows
fogging up, or odors. Your local GM
Service location can help you
determine when it is the right time to
replace your filter.
(2) Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
See Engine Air Cleaner/Filter 0344.
(3) Visually check all fuel and vapor
lines and hoses for proper
attachment, connection, routing, and
condition. (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 fluid. Contaminated
fluid will decrease the life of the
transfer case and/or drive axles and
should be replaced.
(5) Or every five years, whichever
comes first. See Cooling System
0 346.
(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 0357.
(8) Or every 12 months, whichever
comes first. See Wiper Blade
Replacement 0364.
(9) Or every 10 years, whichever
comes first. See Gas Strut(s)0365.
(10) Replace air conditioning
desiccant every seven years.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
0 429.