
Black plate (29,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-29Caution (Continued) be replaced. Do not let
someone put in the wrong
kind of fluid. .
If brake fluid is spilled on the
vehicle's painted surfaces,
the paint finish can be
damaged. Be careful not to
spill brake fluid on the
vehicle. If you do, wash it off
immediately.
Battery Refer to the replacement number
shown on the original battery label
when a new battery is needed. See
Engine Compartment Overview on
page 10-5 for battery location. { WarningBattery posts, terminals, and
related accessories contain lead
and lead compounds, chemicals
known to the State of California to
cause cancer and reproductive
harm. Wash hands after handling.
Vehicle Storage
{ WarningBatteries have acid that can burn
you and gas that can explode.
You can be badly hurt if you are
not careful. See Jump Starting on
page 10-87 for tips on working
around a battery without
getting hurt.
Infrequent Usage: Remove the
black, negative ( − ) cable from the
battery to keep the battery from
running down. Extended Storage: Remove the
black, negative ( − ) cable from the
battery or use a battery trickle
charger.
Four-Wheel Drive Transfer Case When to Check Lubricant
Refer to Maintenance Schedule on
page 11-3 to determine when to
check the lubricant.
1. Fill Plug
2. Drain Plug

Black plate (33,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-33purpose of noise control, prior to
its sale or delivery to the ultimate
purchaser or while it is in use; or
2. The use of the vehicle after such
device or element of design has
been removed or rendered
inoperative by any person.
Among those acts presumed to
constitute tampering are the acts
listed below.
Insulation:
Removal of the noise shields or any
underhood insulation.
Engine:
Removal or rendering engine speed
governor, if the vehicle has one,
inoperative so as to allow engine
speed to exceed manufacturer
specifications. Fan and Drive: .
Removal of fan clutch, if the
vehicle has one, or rendering
clutch inoperative. .
Removal of the fan shroud, if the
vehicle has one.
Air Intake: .
Removal of the air cleaner
silencer. .
Modification of the air cleaner.
Exhaust: .
Removal of the muffler and/or
resonator. .
Removal of the exhaust pipes
and exhaust pipe clamps. Starter Switch Check
{ WarningWhen you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be
sure there is enough room
around the vehicle.
2. Apply both the parking brake
and the regular brake.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each
gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.

Black plate (34,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-34 Vehicle Care
Automatic Transmission
Shift Lock Control
Function Check
{ WarningWhen you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be
sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Apply the parking brake. Be
ready to apply the regular brake
immediately if the vehicle begins
to move.
3. With the engine off, turn the
ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Ignition Transmission
Lock Check While parked and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position. .
The ignition should turn to
LOCK/OFF only when the shift
lever is in P (Park). .
The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required. Park Brake and P (Park)
Mechanism Check
{ WarningWhen you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake. .
To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.

Black plate (36,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-36 Vehicle Care
Headlamp Aiming Headlamp aim has been preset and
should need no further adjustment.
If the vehicle is damaged in a crash,
the headlamp aim may be affected.
If adjustment to the headlamps is
necessary, see your dealer.
Bulb Replacement For the proper type of replacement
bulbs, see Replacement Bulbs on
page 10-40 .
For any bulb ‐ changing procedure
not listed in this section, contact
your dealer.
Halogen Bulbs
{ WarningHalogen bulbs have pressurized
gas inside and can burst if you
drop or scratch the bulb. You or
others could be injured. Be sure
to read and follow the instructions
on the bulb package.
LED Lighting This vehicle has several LED lamps.
For replacement of any LED lighting
assembly, contact your dealer. Headlamps, Front Turn
Signal, Sidemarker, and
Parking Lamps
Driver Side
1. Front Turn Signal/
Sidemarker/Parking Lamp
2. High/Low-Beam Headlamp
See your dealer for passenger side
replacement.
Headlamp
1. Open the hood.

Black plate (50,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-50 Vehicle Care
Wheels and Tires Tires Every new GM vehicle has
high-quality tires made by a
leading tire manufacturer. See
the warranty manual for
information regarding the tire
warranty and where to get
service. For additional
information refer to the tire
manufacturer.
{ Warning.
Poorly maintained and
improperly used tires are
dangerous. .
Overloading the tires can
cause overheating as a
result of too much flexing.
There could be a blowout
(Continued) Warning (Continued)
and a serious crash. See
Vehicle Load Limits on
page 9-15 . .
Underinflated tires pose
the same danger as
overloaded tires. The
resulting crash could
cause serious injury.
Check all tires frequently
to maintain the
recommended pressure.
Tire pressure should be
checked when the tires
are cold. .
Overinflated tires are more
likely to be cut, punctured,
or broken by a sudden
impact — such as when
hitting a pothole. Keep
tires at the recommended
pressure.
(Continued) Warning (Continued) .
Worn or old tires can
cause a crash. If the tread
is badly worn,
replace them. .
Replace any tires that
have been damaged by
impacts with potholes,
curbs, etc. .
Improperly repaired tires
can cause a crash. Only
the dealer or an
authorized tire service
center should repair,
replace, dismount, and
mount the tires. .
Do not spin the tires in
excess of 56 km/h
(35 mph) on slippery
surfaces such as snow,
mud, ice, etc. Excessive
spinning may cause the
tires to explode.

Black plate (60,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-60 Vehicle Care Do not forget the spare tire,
if the vehicle has one. See
Full-Size Spare Tire on
page 10-86 for additional
information.
How to Check
Use a good quality pocket-type
gauge to check tire pressure.
Proper tire inflation cannot be
determined by looking at the tire.
Check the tire inflation pressure
when the tires are cold, meaning
the vehicle has not been driven
for at least three hours or no
more than 1.6 km (1 mi).
Remove the valve cap from the
tire valve stem. Press the tire
gauge firmly onto the valve to
get a pressure measurement.
If the cold tire inflation pressure
matches the recommended
pressure on the Tire and
Loading Information label, no
further adjustment is necessary.
If the inflation pressure is low, add air until the recommended
pressure is reached. If the
inflation pressure is high, press
on the metal stem in the center
of the tire valve to release air.
Re-check the tire pressure with
the tire gauge.
Return the valve caps on the
valve stems to prevent leaks
and keep out dirt and moisture.
Tire Pressure for
High-Speed Operation
{ Warning
Driving at high speeds, 160 km/h
(100 mph) or higher, puts an
additional strain on tires.
Sustained high-speed driving
causes excessive heat buildup
and can cause sudden tire failure.
You could have a crash and you
or others could be killed. Some
(Continued) Warning (Continued) high-speed rated tires require
inflation pressure adjustment for
high-speed operation. When
speed limits and road conditions
are such that a vehicle can be
driven at high speeds, make sure
the tires are rated for high-speed
operation, in excellent condition,
and set to the correct cold tire
inflation pressure for the
vehicle load.
Vehicles with P275/55R20 or P285/
50R20 size tires require inflation
pressure adjustment when driving
the vehicle at speeds of 160 km/h
(100 mph) or higher. Set the cold tire
inflation pressure to 20 kPa (3 psi)
above the recommended cold tire
pressure shown on the Tire and
Loading Information label.

Black plate (62,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-62 Vehicle Care ensure that the replacement or
alternate tires and wheels allow the
TPMS to continue to function
properly.
See Tire Pressure Monitor
Operation on page 10-62 .
See Radio Frequency Statement on
page 13-12 .
Tire Pressure Monitor
Operation This vehicle may have a Tire
Pressure Monitor System (TPMS).
The TPMS is designed to warn the
driver when a low tire pressure
condition exists. TPMS sensors are
mounted onto each tire and wheel
assembly, excluding the spare tire
and wheel assembly. The TPMS
sensors monitor the air pressure in
the tires and transmit the tire
pressure readings to a receiver
located in the vehicle. When a low tire pressure condition
is detected, the TPMS illuminates
the low tire pressure warning light
located on the instrument cluster.
If the warning light comes on, stop
as soon as possible and inflate the
tires to the recommended pressure
shown on the Tire and Loading
Information label. See Vehicle Load
Limits on page 9-15 . A message to check the pressure in
a specific tire displays in the Driver
Information Center (DIC). The low
tire pressure warning light and the
DIC warning message come on at
each ignition cycle until the tires are
inflated to the correct inflation
pressure. Using the DIC, tire
pressure levels can be viewed. For
additional information and details
about the DIC operation and
displays, see Driver Information
Center (DIC) on page 5-27 and Tire
Messages on page 5-38 .
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as the vehicle is driven. This
could be an early indicator that the
air pressure is getting low and
needs to be inflated to the proper
pressure.

Black plate (63,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-63A Tire and Loading Information label
shows the size of the original
equipment tires and the correct
inflation pressure for the tires when
they are cold. See Vehicle Load
Limits on page 9-15 , for an example
of the Tire and Loading Information
label and its location. Also see Tire
Pressure on page 10-59 .
The TPMS can warn about a low
tire pressure condition but it does
not replace normal tire
maintenance. See Tire Inspection
on page 10-65 , Tire Rotation on
page 10-65 , and Tires on
page 10-50 .
{ Caution
Tire sealant materials are not all
the same. A non-approved tire
sealant could damage the TPMS
sensors. TPMS sensor damage
caused by using an incorrect tire
sealant is not covered by the
vehicle warranty. Always use only
(Continued) Caution (Continued) the GM approved tire sealant
available through your dealer or
included in the vehicle.
TPMS Malfunction Light and
Message The TPMS will not function properly
if one or more of the TPMS sensors
are missing or inoperable. When the
system detects a malfunction, the
low tire pressure warning light
flashes for about one minute and
then stays on for the remainder of
the ignition cycle. A DIC warning
message also displays. The
malfunction light and DIC warning
message come on at each ignition
cycle until the problem is corrected.
Some of the conditions that can
cause these to come on are: .
One of the road tires has been
replaced with the spare tire. The
spare tire does not have a
TPMS sensor. The malfunction light and the DIC message
should go off after the road tire
is replaced and the sensor
matching process is performed
successfully. See “ TPMS Sensor
Matching Process ” later in this
section. .
The TPMS sensor matching
process was not done or not
completed successfully after
rotating the tires. The
malfunction light and the DIC
message should go off after
successfully completing the
sensor matching process. See
“ TPMS Sensor Matching
Process ” later in this section. .
One or more TPMS sensors are
missing or damaged. The
malfunction light and the DIC
message should go off when the
TPMS sensors are installed and
the sensor matching process is
performed successfully. See
your dealer for service.