2015 GMC SIERRA DENALI gas type

Black plate (22,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
3-22 Seats and Restraints capable. If the airbags are rollover
capable, both roof-rail airbags will
also inflate if the sensing system
predicts that the vehicle is about to
roll over on its side. The roof-rail
airbags are not designed to inflate in
rear impacts.
In any particular crash, no one can
say whether an airbag should have
inflated simply because of the
vehicle damage or repair costs.
What Makes an Airbag
Inflate? In a deployment event, the sensing
system sends an electrical signal
triggering a release of gas from the
inflator. Gas from the inflator fills the
airbag causing the bag to break out
of the cover. The inflator, the airbag,
and related hardware are all part of
the airbag module.
For airbag locations, see Where Are
the Airbags? on page 3-18 .How Does an Airbag
Restrain? In moderate to severe frontal or
near frontal collisions, even belted
occupants can contact the steering
wheel or the instrument panel. In
moderate to severe side collisions,
even belted occupants can contact
the inside of the vehicle.
Airbags supplement the protection
provided by safety belts by
distributing the force of the impact
more evenly over the
occupant's body.
Rollover capable roof-rail airbags
are designed to help contain the
head and chest of occupants in the
outboard seating positions in the
first and second rows. The rollover
capable roof-rail airbags are
designed to help reduce the risk of
full or partial ejection in rollover
events, although no system can
prevent all such ejections. But airbags would not help in many
types of collisions, primarily
because the occupant's motion is
not toward those airbags. See When
Should an Airbag Inflate? on
page 3-20 .
Airbags should never be regarded
as anything more than a supplement
to safety belts.
What Will You See after
an Airbag Inflates? After the frontal airbags and
seat-mounted side impact airbags
inflate, they quickly deflate, so
quickly that some people may not
even realize an airbag inflated.
Roof-rail airbags may still be at least
partially inflated for some time after
they inflate. Some components of
the airbag module may be hot for
several minutes. For location of the
airbags, see Where Are the
Airbags? on page 3-18 .
The parts of the airbag that come
into contact with you may be warm,
but not too hot to touch. There may

Black plate (64,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-64 Driving and Operating
{ CautionDo not use fuel containing
methanol. It can corrode metal
parts in the fuel system and also
damage plastic and rubber parts.
That damage would not be
covered under the vehicle
warranty.
Some gasolines, mainly high octane
racing gasolines, can contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). Do not use
gasolines and/or fuel additives with
MMT as they can reduce spark plug
life and affect emission control
system performance. The
malfunction indicator lamp may turn
on. If this occurs, see your dealer
for service. California Fuel
Requirements If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. See
the underhood emission control
label. If this fuel is not available in
states adopting California Emissions
Standards, the vehicle will operate
satisfactorily on fuels meeting
federal specifications, but emission
control system performance might
be affected. The malfunction
indicator lamp could turn on and the
vehicle may not pass a smog-check
test. See Malfunction Indicator
Lamp on page 5-18 . If this occurs,
return to your authorized dealer for
diagnosis. If it is determined that the
condition is caused by the type of
fuel used, repairs may not be
covered by the vehicle warranty. Fuels in Foreign
Countries If planning to drive in countries
outside the U.S. or Canada, the
proper fuel might be hard to find.
Check regional auto club or fuel
retail brand websites for availability
in the country where driving. Never
use leaded gasoline, fuel containing
methanol, manganese, or any other
fuel not recommended. Costly
repairs caused by use of improper
fuel would not be covered by the
vehicle warranty.
Fuel Additives To keep fuel systems clean, TOP
TIER Detergent Gasoline is
recommended. See Fuel on
page 9-63 .
If TOP TIER Detergent Gasoline is
not available, one bottle of Fuel
System Treatment PLUS added to
the fuel tank at every engine oil
change can help. Fuel System
Treatment PLUS is the only

Black plate (67,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-67Be careful not to spill fuel. Do not
top off or overfill the tank and wait a
few seconds after you have finished
pumping before removing the
nozzle. Clean fuel from painted
surfaces as soon as possible. See
Exterior Care on page 10-96 .
When replacing the fuel cap, turn it
clockwise until it clicks. It will require
more effort to turn the fuel cap on
the last turn as you tighten it. Make
sure the cap is fully installed. The
diagnostic system can determine if
the fuel cap has been left off or
improperly installed. This would
allow fuel to evaporate into the
atmosphere. See Malfunction
Indicator Lamp on page 5-18 .
The TIGHTEN GAS CAP message
displays on the Driver Information
Center (DIC) if the fuel cap is not
properly installed. See Fuel System
Messages on page 5-35 for more
information. { WarningIf a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel by
shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
{ CautionIf a new fuel cap is needed, be
sure to get the right type of cap
from your dealer. The wrong type
of fuel cap may not fit properly,
may cause the malfunction
indicator lamp to light, and could
damage the fuel tank and
emissions system. See
Malfunction Indicator Lamp on
page 5-18 . Filling a Portable Fuel
Container
{ WarningFilling a portable fuel container
while it is in the vehicle can cause
fuel vapors that can ignite either
by static electricity or other
means. You or others could be
badly burned and the vehicle
could be damaged. Always: .
Use approved fuel
containers. .
Remove the container from
the vehicle, trunk, or pickup
bed before filling. .
Place the container on the
ground. .
Place the nozzle inside the fill
opening of the container
before dispensing fuel, and
(Continued)

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 (87,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-87The vehicle may have a different
size spare tire than the road tires
originally installed on the vehicle.
This spare tire was developed for
use on this vehicle, so it is all right
to drive on it. If the vehicle has
four-wheel drive and a different size
spare tire is installed, drive only in
two-wheel drive.
After installing the spare tire on the
vehicle, stop as soon as possible
and check that the spare tire is
correctly inflated.
Have the damaged or flat road tire
repaired or replaced and installed
back onto the vehicle as soon as
possible so the spare tire will be
available in case it is needed again.
Do not mix tires and wheels of
different sizes, because they will not
fit. Keep your spare tire and its
wheel together. If the vehicle has a
spare tire that does not match the
original road tires and wheels in size
and type, do not include the spare in
the tire rotation. Jump Starting For more information about the
vehicle battery, see Battery on
page 10-29 .
If the vehicle's battery (or batteries)
has run down, you may want to use
another vehicle and some jumper
cables to start your vehicle. Be sure
to use the following steps to do it
safely.
{ WarningBatteries can hurt you. They can
be dangerous because: .
They contain acid that can
burn you. .
They contain gas that can
explode or ignite. .
They contain enough
electricity to burn you.
If you do not follow these steps
exactly, some or all of these
things can hurt you. { CautionIgnoring these steps could result
in costly damage to the vehicle
that would not be covered by the
vehicle warranty. Trying to start
the vehicle by pushing or pulling it
will not work, and it could damage
the vehicle.
1. Check the other vehicle. It must
have a 12-volt battery with a
negative ground system.
{ Caution
If the other vehicle does not have
a 12-volt system with a negative
ground, both vehicles can be
damaged. Only use a vehicle that
has a 12-volt system with a
negative ground for jump starting.
2. If you have a vehicle with a
diesel engine with two batteries,
you should know before you