Black plate (11,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-11
suspension, wheels, tires, and
exhaust system for damage and
check the fuel lines and cooling
system for any leakage.
More frequent maintenance service
is required. See theMaintenance
Schedule on page 11-3.
Driving on Wet Roads
Rain and wet roads can reduce
vehicle traction and affect your
ability to stop and accelerate.
Always drive slower in these types
of driving conditions and avoid
driving through large puddles and
deep‐standing or flowing water.
{Warning
Wet brakes can cause crashes.
They might not work as well in a
quick stop and could cause
pulling to one side. You could
lose control of the vehicle.
(Continued)
Warning (Continued)
After driving through a large
puddle of water or a car/vehicle
wash, lightly apply the brake
pedal until the brakes work
normally.
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause the
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be
very cautious about trying to drive
through flowing water.
Hydroplaning
Hydroplaning is dangerous. Water
can build up under the vehicle's
tires so they actually ride on the
water. This can happen if the road is
wet enough and you are going fast
enough. When the vehicle is
hydroplaning, it has little or no
contact with the road. There is no hard and fast rule about
hydroplaning. The best advice is to
slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet
weather driving tips include:
.Allow extra following distance.
.Pass with caution.
.Keep windshield wiping
equipment in good shape.
.Keep the windshield washer fluid
reservoir filled.
.Have good tires with proper
tread depth. See
Tires on
page 10-50.
.Turn off cruise control.
Hill and Mountain Roads
Driving on steep hills or through
mountains is different than driving
on flat or rolling terrain. Tips for
driving in these conditions include:
.Keep the vehicle serviced and in
good shape.
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
{Caution
Do 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 9-67
Be 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. SeeMalfunction
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.{Warning
If 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.
{Caution
If 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
{Warning
Filling 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 (83,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-83
Operating the vehicle in Tow/Haul
when lightly loaded or with no trailer
at all will not cause damage.
However, there is no benefit to the
selection of Tow/Haul when the
vehicle is unloaded. Such a
selection when unloaded may result
in unpleasant engine and
transmission driving characteristics
and reduced fuel economy. Tow/
Haul is recommended only when
pulling a heavy trailer or a large or
heavy load.
Integrated Trailer Brake
Control System
The vehicle may have an Integrated
Trailer Brake Control (ITBC) system
for use with electric trailer brakes or
most electric over hydraulic trailer
brakes.
This symbol is on the Trailer Brake
Control Panel on vehicles with an
ITBC system. The power output to
the trailer brakes is based on the
amount of brake pressure being
applied by the vehicle’s brake
system, and on the type of trailer
brakes detected. This available
power output to the trailer brakes
can be adjusted to a wide range of
trailering situations.
The ITBC system is integrated with
the vehicle’s brake, antilock brake,
and StabiliTrak systems. In trailering
conditions that cause the vehicle’s
antilock brake or StabiliTrak
systems to activate, power sent to
the trailer's brakes will be
automatically adjusted to minimize
trailer wheel lock-up. This does not
imply that the trailer has StabiliTrak.
If the vehicle’s brake, antilock brake,
or StabiliTrak systems are not
functioning properly, the ITBC
system may not be fully functional
or may not function at all. Make sure all of these systems are fully
operational to ensure full
functionality of the ITBC system.
The ITBC system is powered
through the vehicle's electrical
system. Turning the ignition off will
also turn off the ITBC system. The
ITBC system is fully functional only
when the ignition is in ON/RUN.
{Warning
Connecting a trailer that has an
air brake system may result in
reduced or complete loss of trailer
braking. There may be an
increase in stopping distance or
trailer instability which could
result in personal injury or
damage to the vehicle, trailer,
or other property. Use the ITBC
system only with electric or
electric over hydraulic trailer
brakes.
Black plate (6,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
13-6 Customer Information
.Model, year, color, and license
plate number of the vehicle.
.Odometer reading, Vehicle
Identification Number (VIN), and
delivery date of the vehicle.
.Description of the problem.
Coverage
Services are provided up to 5 years/
160 000 km (100,000 mi), whichever
comes first.
In the U.S., anyone driving the
vehicle is covered. In Canada, a
person driving the vehicle without
permission from the owner is not
covered.
Roadside Assistance is not a part of
the New Vehicle Limited Warranty.
General Motors North America and
GMC reserve the right to make any
changes or discontinue the
Roadside Assistance program at
any time without notification.
General Motors North America and
GMC reserve the right to limit
services or payment to an owner ordriver if they decide the claims are
made too often, or the same type of
claim is made many times.
Services Provided
.Emergency Fuel Delivery:
Delivery of enough fuel for the
vehicle to get to the nearest
service station.
.Lock-Out Service:
Service to
unlock the vehicle if you are
locked out. A remote unlock may
be available if you have
OnStar
®. For security reasons,
the driver must present
identification before this service
is given.
.Emergency Tow from a Public
Road or Highway: Tow to the
nearest GMC dealer for warranty
service, or if the vehicle was in a
crash and cannot be driven.
Assistance is not given when the
vehicle is stuck in the sand,
mud, or snow.
.Flat Tire Change: Service to
change a flat tire with the spare
tire. The spare tire, if equipped,
must be in good condition and
properly inflated. It is the owner's
responsibility for the repair or
replacement of the tire if it is not
covered by the warranty.
.Battery Jump Start: Service to
jump start a dead battery.
.Trip Interruption Benefits and
Assistance: If your trip is
interrupted due to a warranty
failure, incidental expenses may
be reimbursed during the
5 years/(160 000 km) 100,000 mi
Powertrain warranty period.
Items considered are hotel,
meals, and rental car.
Services Not Included in
Roadside Assistance
.Impound towing caused by
violation of any laws.
.Legal fines.