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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 4336. 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
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
448 Service and Maintenance
Maintenance
Schedule Owner Checks and Services At Each Fuel Stop
.
Check the engine oil level. See
Engine Oil 0 350 .
Once a Month
.
Check the tire inflation
pressures. See Tire Pressure
0 397 .
.
Inspect the tires for wear. See
Tire Inspection 0 404 .
.
Check the windshield washer
fluid level. See Washer Fluid
0 366 .
Engine Oil Change When the CHANGE ENGINE OIL
SOON message displays, have the
engine oil and filter changed within
the next 1 000 km/600 mi. If driven
under the best conditions, the
engine oil life system may not
indicate the need for vehicle service
for up to a year. The engine oil and filter must be changed at least once
a year and the oil life system must
be reset. Your trained dealer
technician can perform this work.
If the engine oil life system is reset
accidentally, service the vehicle
within 5 000 km/3,000 mi since the
last service. Reset the oil life
system when the oil is changed.
See Engine Oil Life System 0 353 .
Passenger Compartment Air
Filter The passenger compartment air
filter removes dust, pollen, and
other airborne irritants from outside
air that is pulled into the vehicle.
The filter should be replaced as part
of routine scheduled maintenance.
Inspect the passenger compartment
air filter every 36 000 km/
22,500 miles or two years,
whichever comes first. Replace if
necessary. More frequent
replacement may be needed if the
vehicle is driven in areas with heavy
traffic, areas with poor air quality,
or areas with high dust levels. Replacement may also be needed if
there is a reduction in air flow,
excessive window fogging, or odors.
Tire Rotation and Required
Services Every 12 000 km/
7,500 mi Rotate the tires, if recommended for
the vehicle, and perform the
following services. See Tire
Rotation 0 405 .
.
Check engine oil level and oil
life percentage. If needed,
change engine oil and filter, and
reset oil life system. See Engine
Oil 0 350 and Engine Oil Life
System 0 353 .
.
Check engine coolant level. See
Cooling System 0 359 .
.
Check windshield washer fluid
level. See Washer Fluid 0 366 .
.
Visually inspect windshield wiper
blades for wear, cracking,
or contamination. See Exterior
Care 0 435 . Replace worn or
damaged wiper blades. See
Wiper Blade Replacement
0 375 .
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GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Customer Information 477
Reporting Safety Defects
to General Motors In addition to notifying NHTSA (or
Transport Canada) in a situation like
this, notify General Motors.
Call 1-800-GMC-8782
(1-800-462-8782), or write:
GMC Customer Assistance Center
P.O. Box 33172
Detroit, MI 48232-5172
In Canada, call 1-800-263-3777
(English) or 1-800-263-7854
(French), or write:
General Motors of Canada
Company
Customer Care Centre,
Mail Code: CA1-163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
In Mexico, call 01-800-466-0801.
In other Central America and
Caribbean Countries, call
52-722-236-0680. Vehicle Data
Recording and
Privacy The vehicle has a number of
computers that record information
about the vehicle ’ s performance and
how it is driven. For example, the
vehicle uses computer modules to
monitor and control engine and
transmission performance, to
monitor the conditions for airbag
deployment and deploy them in a
crash, and, if equipped, to provide
antilock braking to help the driver
control the vehicle. These modules
may store data to help the dealer
technician service the vehicle.
Some modules may also store data
about how the vehicle is operated,
such as rate of fuel consumption or
average speed. These modules may
retain personal preferences, such as
radio presets, seat positions, and
temperature settings. Event Data Recorders This vehicle is equipped with an
event data recorder (EDR). The
main purpose of an EDR is to
record, in certain crash or near
crash-like situations, such as an air
bag deployment or hitting a road
obstacle, data that will assist in
understanding how a vehicle ’ s
systems performed. The EDR is
designed to record data related to
vehicle dynamics and safety
systems for a short period of time,
typically 30 seconds or less. The
EDR in this vehicle is designed to
record such data as:
.
How various systems in your
vehicle were operating;
.
Whether or not the driver and
passenger safety belts were
buckled/fastened;
.
How far (if at all) the driver was
depressing the accelerator and/
or brake pedal; and,
.
How fast the vehicle was
traveling.