
Black plate (26,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-26 Vehicle Care
Open the cap with the washer
symbol on it. Add washer fluid until
the tank is full. See Engine
Compartment Overview on
page 10-5 for reservoir location.
{ Caution.
Do not use engine coolant
(antifreeze) in the windshield
washer. It can damage the
windshield washer system
and paint. .
Do not mix water with
ready-to-use washer fluid.
Water can cause the solution
to freeze and damage the
washer fluid tank and other
parts of the washer system.
(Continued) Caution (Continued) .
When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water. .
Fill the washer fluid tank only
three-quarters full when it is
very cold. This allows for fluid
expansion if freezing occurs,
which could damage the tank
if it is completely full.
Brakes This vehicle has front and rear disc
brakes.
Disc brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or be
heard all the time the vehicle is
moving, except when applying the
brake pedal firmly. { WarningThe brake wear warning sound
means that soon the brakes will
not work well. That could lead to
a crash. When the brake wear
warning sound is heard, have the
vehicle serviced.
{ CautionContinuing to drive with worn-out
brake pads could result in costly
brake repair.
Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake pads for wear and
evenly tighten wheel nuts in the

Black plate (10,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
11-10 Service and Maintenance 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
of leaking, blown seals,
or damage, and can advise
when service is needed.
Tires
Tires need to be properly inflated,
rotated, and balanced. Maintaining
the tires can save money and fuel,
and can reduce the risk of tire
failure. .
Signs that the tires need to be
replaced include three or more
visible treadwear indicators; cord
or fabric showing through the rubber; cracks or cuts in the
tread or sidewall; or a bulge or
split in the tire. .
Trained dealer technicians can
inspect and recommend the right
tires. Your dealer can also
provide tire/wheel balancing
services to ensure smooth
vehicle operation at all speeds.
Your dealer sells and services
name brand tires.
Vehicle Care
To help keep the vehicle looking like
new, vehicle care products are
available from your dealer. For
information on how to clean and
protect the vehicle ’ s interior and
exterior, see Interior Care on
page 10-101 and Exterior Care on
page 10-96 .

Black plate (5,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
INDEX i-5FlexFuel
E85 . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-65
Floor Console Storage . . . . . . . . . . 4-3
Floor Mats . . . . . . . . . . . . . . . . . . .10-105
Fluid
Automatic
Transmission . . . . . . . 10-12, 10-15
Brakes . . . . . . . . . . . . . . . . . . . . . . 10-27
Four-Wheel Drive
Transfer Case . . . . . . . . . . . . . . . 9-40
Power Steering . . . . . . . . . . . . . 10-24
Washer . . . . . . . . . . . . . . . . . . . . . 10-25
Fog Lamps . . . . . . . . . . . . . . . . . . . . . 6-5
Bulb Replacement . . . . . . . . . . 10-37
Folding Mirrors . . . . . . . . . . . . . . . . 2-16
Forward Collision Alert
(FCA) System . . . . . . . . . . . . . . . . 9-59
Four-Wheel Drive . . . . . . . 9-40, 10-29
Four-Wheel-Drive Light . . . . . . . . 5-22
Frequency Statement
Radio . . . . . . . . . . . . . . . . . . . . . . . 13-12
Front Axle . . . . . . . . . . . . . . . . . . . . 10-30 Front Fog Lamp
Light . . . . . . . . . . . . . . . . . . . . . . . . . . 5-26
Front Seats
Heated and Cooled . . . . . . . . . . . . 3-7
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-63
Additives . . . . . . . . . . . . . . . . . . . . . 9-64
Economy Driving . . . . . . . . . . . . . 1-21
Filling a Portable Fuel
Container . . . . . . . . . . . . . . . . . . . 9-67
Filling the Tank . . . . . . . . . . . . . . . 9-66
Foreign Countries . . . . . . . . . . . . 9-64
Gauge . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Low Fuel Warning Light . . . . . . . 5-25
Management, Active . . . . . . . . . . 9-32
Requirements, California . . . . . 9-64
System Messages . . . . . . . . . . . . 5-35
Full-Size Spare Tire . . . . . . . . . . 10-86
Fuses . . . . . . . . . . . . . . . . . . . . . . . . 10-41
Engine Compartment
Fuse Block . . . . . . . . . . . . . . . . 10-41
Instrument Panel
Fuse Block . . . . . . . . . 10-45, 10-48 G Garage Door Opener . . . . . . . . . . 5-49
Programming . . . . . . . . . . . . . . . . . 5-49
Gauges
Engine Coolant
Temperature . . . . . . . . . . . . . . . . 5-13
Engine Oil Pressure . . . . . . . . . . 5-12
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 5-12
Odometer . . . . . . . . . . . . . . . . . . . . . 5-11
Speedometer . . . . . . . . . . . . . . . . . 5-11
Tachometer . . . . . . . . . . . . . . . . . . . 5-11
Transmission Temperature . . . . 5-14
Trip Odometer . . . . . . . . . . . . . . . . 5-11
Voltmeter . . . . . . . . . . . . . . . . . . . . . 5-15
Warning Lights and
Indicators . . . . . . . . . . . . . . . . . . . . 5-8
General Information
Service and Maintenance . . . . . 11-1
Towing . . . . . . . . . . . . . . . . . . . . . . . . 9-68
Vehicle Care . . . . . . . . . . . . . . . . . . 10-2
Glass Replacement . . . . . . . . . . . 10-35
Glove Box . . . . . . . . . . . . . . . . . . . . . . 4-1
GM Mobility Reimbursement
Program . . . . . . . . . . . . . . . . . . . . . . 13-5

Black plate (9,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
INDEX i-9OnStar ®
Security . . . . . . . . . . . . . . 14-3
OnStar ®
Vehicle
Diagnostics . . . . . . . . . . . . . . . . . . 14-6
Operating Mode
Overheated Engine
Protection . . . . . . . . . . . . . . . . . 10-23
Ordering
Service Publications . . . . . . . . .13-11
Outlets
Power . . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Overheated Engine
Protection
Operating Mode . . . . . . . . . . . . . 10-23
Overheating, Engine . . . . . . . . . . 10-21
PPark
Shifting Into . . . . . . . . . . . . . . . . . . . 9-30
Shifting Out of . . . . . . . . . . . . . . . . 9-31
Parking
Brake . . . . . . . . . . . . . . . . . . . . . . . . . 9-47
Brake and P (Park)
Mechanism Check . . . . . . . . 10-34
Over Things That Burn . . . . . . . 9-32 Parking or Backing
Assistance Systems . . . . . . . . . . 9-56
Passenger Airbag Status
Indicator . . . . . . . . . . . . . . . . . . . . . 5-17
Passenger Compartment Air
Filter . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
Passenger Sensing System . . . 3-24
Perchlorate Materials
Requirements, California . . . . . 10-3
Personalization
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 5-42
Pickup Conversion to
Chassis Cab . . . . . . . . . . . . . . . . . 9-92
Power
Door Locks . . . . . . . . . . . . . . . . . . . . 2-9
Mirrors . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Outlets . . . . . . . . . . . . . . . . . . . . . . . . 5-5
Protection, Battery . . . . . . . . . . . . . 6-9
Retained Accessory (RAP) . . . 9-29
Seat Adjustment . . . . . . . . . . . . . . . 3-3
Steering Fluid . . . . . . . . . . . . . . . 10-24
Windows . . . . . . . . . . . . . . . . . . . . . 2-19
Pregnancy, Using Safety
Belts . . . . . . . . . . . . . . . . . . . . . . . . . 3-15
Privacy
Vehicle Data Recording . . . . . 13-14 Program
Courtesy Transportation . . . . . . 13-8
Proposition 65 Warning,
California . . . . . . . . . . . . . . . . . . . . . 10-2
R Radio Frequency
Identification (RFID) . . . . . . . . . 13-12
Radio Frequency
Statement . . . . . . . . . . . . . . . . . . . 13-12
Reading Lamps . . . . . . . . . . . . . . . . . 6-7
Rear Axle . . . . . . . . . . . . . . . . . . . . . 10-31
Locking . . . . . . . . . . . . . . . . . . . . . . . 9-52
Rear Seats . . . . . . . . . . . . . . . . . . . . . 3-9
Rear Windows . . . . . . . . . . . . . . . . . 2-22
Rearview Mirrors
Automatic Dimming . . . . . . . . . . . 2-19
Reclining Seatbacks . . . . . . . . . . . . 3-4
Recommended Fluids and
Lubricants . . . . . . . . . . . . . . . . . . . 11-12
Records
Maintenance . . . . . . . . . . . . . . . . .11-16
Recreational Vehicle
Towing . . . . . . . . . . . . . . . . . . . . . . 10-91
Reimbursement Program,
GM Mobility . . . . . . . . . . . . . . . . . . 13-5