air condition GMC SIERRA DENALI 2015 Service Manual

Black plate (71,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-71brakes, rollover airbags, traction
control, electronic stability control,
or All-Wheel Drive, the performance
of these systems can also be
affected.
{ WarningIf different sized wheels are used,
there may not be an acceptable
level of performance and safety if
tires not recommended for those
wheels are selected. This
increases the chance of a crash
and serious injury. Only use GM
specific wheel and tire systems
developed for the vehicle, and
have them properly installed by a
GM certified technician.
See Buying New Tires on
page 10-69 and Accessories and
Modifications on page 10-3 .Uniform Tire Quality
Grading Quality grades can be found
where applicable on the tire
sidewall between tread shoulder
and maximum section width. For
example:
Treadwear 200 Traction AA
Temperature A
The following information relates
to the system developed by the
United States National Highway
Traffic Safety Administration
(NHTSA), which grades tires by
treadwear, traction, and
temperature performance. This
applies only to vehicles sold in
the United States. The grades
are molded on the sidewalls of
most passenger car tires. The
Uniform Tire Quality Grading
(UTQG) system does not apply
to deep tread, winter tires,
compact spare tires, tires with nominal rim diameters of
10 to 12 inches (25 to 30 cm),
or to some limited-production
tires.
While the tires available on
General Motors passenger cars
and light trucks may vary with
respect to these grades, they
must also conform to federal
safety requirements and
additional General Motors Tire
Performance Criteria (TPC)
standards.
All Passenger Car Tires Must
Conform to Federal Safety
Requirements In Addition To
These Grades.
Treadwear
The treadwear grade is a
comparative rating based on the
wear rate of the tire when tested
under controlled conditions on a
specified government test
course. For example, a tire

Black plate (73,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-73surface variations such as troughs
or ruts, is normal. If the vehicle is
vibrating when driving on a smooth
road, the tires and wheels may need
to be rebalanced. See your dealer
for proper diagnosis.
Wheel Replacement Replace any wheel that is bent,
cracked, or badly rusted or
corroded. If wheel nuts keep coming
loose, the wheel, wheel bolts and
wheel nuts should be replaced.
If the wheel leaks air, replace it.
Some aluminum wheels can be
repaired. See your dealer if any of
these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have the
same load-carrying capacity,
diameter, width, offset and be
mounted the same way as the one it
replaces. Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor
System (TPMS) sensors with new
GM original equipment parts.
{ WarningUsing the wrong replacement
wheels, wheel bolts, or wheel
nuts can be dangerous. It could
affect the braking and handling of
the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. Always use the correct
wheel, wheel bolts, and wheel
nuts for replacement.
{ Caution
The wrong wheel can also cause
problems with bearing life, brake
cooling, speedometer or
odometer calibration, headlamp
aim, bumper height, vehicle
(Continued) Caution (Continued) ground clearance, and tire or tire
chain clearance to the body and
chassis.
Whenever a wheel, wheel bolt,
or wheel nut is replaced on a dual
wheel setup, check the wheel nut
torque after 160, 1 600 and
10 000 km (100, 1,000 and 6,000 mi)
of driving. For proper torque, see
“ Wheel Nut Torque ” under
Capacities and Specifications on
page 12-2 .
See If a Tire Goes Flat on
page 10-74 for more information.
Used Replacement Wheels
{ Warning
Replacing a wheel with a used
one is dangerous. How it has
been used or how far it has been
(Continued)

Black plate (74,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-74 Vehicle Care Warning (Continued)driven may be unknown. It could
fail suddenly and cause a crash.
When replacing wheels, use a
new GM original equipment
wheel.
Tire Chains
{ WarningDo not use tire chains. There is
not enough clearance. Tire chains
used on a vehicle without the
proper amount of clearance can
cause damage to the brakes,
suspension, or other vehicle
parts. The area damaged by the
tire chains could cause loss of
control and a crash. Use another
type of traction device only if its
manufacturer recommends it for
the vehicle's tire size combination
and road conditions. Follow that
(Continued) Warning (Continued) manufacturer's instructions. To
avoid vehicle damage, drive
slowly and readjust or remove the
traction device if it contacts the
vehicle. Do not spin the wheels.
If traction devices are used, install
them on the rear tires.
If a Tire Goes Flat It is unusual for a tire to blowout
while driving, especially if the tires
are maintained properly. If air goes
out of a tire, it is much more likely to
leak out slowly. But if there ever is a
blowout, here are a few tips about
what to expect and what to do:
If a front tire fails, the flat tire
creates a drag that pulls the vehicle
toward that side. Take your foot off
the accelerator pedal and grip the
steering wheel firmly. Steer to
maintain lane position, and then
gently brake to a stop, well off the
road, if possible. A rear blowout, particularly on a
curve, acts much like a skid and
may require the same correction as
used in a skid. Stop pressing the
accelerator pedal and steer to
straighten the vehicle. It may be
very bumpy and noisy. Gently brake
to a stop, well off the road,
if possible.
{ WarningDriving on a flat tire will cause
permanent damage to the tire.
Re-inflating a tire after it has been
driven on while severely
underinflated or flat may cause a
blowout and a serious crash.
Never attempt to re-inflate a tire
that has been driven on while
severely underinflated or flat.
Have your dealer or an authorized
tire service center repair or
replace the flat tire as soon as
possible.

Black plate (99,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-99emblems, decals and stripes. Follow
instructions under "Washing the
Vehicle" previously in this section.
Lamp covers are made of plastic,
and some have a UV protective
coating. Do not clean or wipe them
while they are dry.
Do not use any of the following on
lamp covers: .
Abrasive or caustic agents. .
Washer fluids and other cleaning
agents in higher concentrations
than suggested by the
manufacturer. .
Solvents, alcohols, fuels,
or other harsh cleaners. .
Ice scrapers or other hard items. .
Aftermarket appearance caps or
covers while the lamps are
illuminated, due to excessive
heat generated. { CautionFailure to clean lamps properly
can cause damage to the lamp
cover that would not be covered
by the vehicle warranty.
{ CautionUsing wax on low gloss black
finish stripes can increase the
gloss level and create a
non-uniform finish. Clean low
gloss stripes with soap and
water only.
Air Intakes
Clear debris from the air intakes,
between the hood and windshield,
when washing the vehicle.
Windshield and Wiper Blades
Clean the outside of the windshield
with glass cleaner. Clean rubber blades using a lint-free
cloth or paper towel soaked with
windshield washer fluid or a mild
detergent. Wash the windshield
thoroughly when cleaning the
blades. Bugs, road grime, sap, and
a buildup of vehicle wash/wax
treatments may cause wiper
streaking.
Replace the wiper blades if they are
worn or damaged. Damage can be
caused by extreme dusty
conditions, sand, salt, heat, sun,
snow, and ice.
Weatherstrips Apply Dielectric silicone grease on
weatherstrips to make them last
longer, seal better, and not stick or
squeak. Lubricate weatherstrips
once a year. Hot, dry climates may
require more frequent application.
Black marks from rubber material on
painted surfaces can be removed by
rubbing with a clean cloth. See
Recommended Fluids and
Lubricants on page 11-12 .

Black plate (100,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-100 Vehicle Care Tires Use a stiff brush with tire cleaner to
clean the tires.
{ CautionUsing petroleum-based tire
dressing products on the vehicle
may damage the paint finish and/
or tires. When applying a tire
dressing, always wipe off any
overspray from all painted
surfaces on the vehicle.
Wheels and Trim — Aluminum
or Chrome Use a soft, clean cloth with mild
soap and water to clean the wheels.
After rinsing thoroughly with clean
water, dry with a soft, clean towel.
A wax may then be applied. { CautionChrome wheels and other chrome
trim may be damaged if the
vehicle is not washed after driving
on roads that have been sprayed
with magnesium, calcium,
or sodium chloride. These
chlorides are used on roads for
conditions such as ice and dust.
Always wash the chrome with
soap and water after exposure.
{ Caution
To avoid surface damage, do not
use strong soaps, chemicals,
abrasive polishes, cleaners,
brushes, or cleaners that contain
acid on aluminum or
chrome-plated wheels. Use only
approved cleaners. Also, never
drive a vehicle with aluminum or
chrome-plated wheels through an
(Continued) Caution (Continued) automatic car wash that uses
silicone carbide tire cleaning
brushes. Damage could occur
and the repairs would not be
covered by the vehicle warranty.
Steering, Suspension, and
Chassis Components Visually inspect steering,
suspension, and chassis
components for damaged, loose,
or missing parts or signs of wear at
least once a year.
Inspect power steering for proper
hook-up, binding, leaks, cracks,
chafing, etc.
Visually check constant velocity joint
boots and axle seals for leaks.
1500 Series vehicles, at least every
other oil change lubricate the outer
tie rod ends.

Black plate (104,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-104 Vehicle Care
{ CautionDo not attach a device with a
suction cup to the display. This
may cause damage and would
not be covered by the warranty.
Instrument Panel, Leather,
Vinyl, Other Plastic Surfaces,
Low Gloss Paint Surfaces and
Natural Open Pore Wood
Surfaces Use a soft microfiber cloth
dampened with water to remove
dust and loose dirt. For a more
thorough cleaning, use a soft
microfiber cloth dampened with a
mild soap solution.
{ Caution
Soaking or saturating leather,
especially perforated leather, as
well as other interior surfaces,
(Continued) Caution (Continued) may cause permanent damage.
Wipe excess moisture from these
surfaces after cleaning and allow
them to dry naturally. Never use
heat, steam, spot lifters, or spot
removers. Do not use cleaners
that contain silicone or wax-based
products. Cleaners containing
these solvents can permanently
change the appearance and feel
of leather or soft trim and are not
recommended.
Do not use cleaners that increase
gloss, especially on the instrument
panel. Reflected glare can decrease
visibility through the windshield
under certain conditions. { CautionUse of air fresheners may cause
permanent damage to plastics
and painted surfaces. If an air
freshener comes in contact with
any plastic or painted surface in
the vehicle, blot immediately and
clean with a soft cloth dampened
with a mild soap solution.
Damage caused by air fresheners
would not be covered by the
vehicle warranty.
Care of Safety Belts Keep belts clean and dry.
{ Warning
Do not bleach or dye safety belts.
It may severely weaken them. In
a crash, they might not be able to
provide adequate protection.
Clean safety belts only with mild
soap and lukewarm water.

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Service and Maintenance 11-1
Service and
Maintenance General Information General Information . . . . . . . . . . 11-1
Maintenance Schedule Maintenance Schedule . . . . . . . 11-3
Special Application Services Special Application
Services . . . . . . . . . . . . . . . . . . . . 11-8
Additional Maintenance
and Care Additional Maintenance
and Care . . . . . . . . . . . . . . . . . . . 11-9
Recommended Fluids,
Lubricants, and Parts Recommended Fluids and
Lubricants . . . . . . . . . . . . . . . . . 11-12
Maintenance Replacement
Parts . . . . . . . . . . . . . . . . . . . . . . 11-14
Maintenance Records
Maintenance Records . . . . . . 11-16 General Information This maintenance section applies to
vehicles with a gasoline engine. For
diesel engine vehicles, see the
maintenance schedule section in
the Duramax diesel supplement.
Your vehicle is an important
investment. This section describes
the required maintenance for the
vehicle. Follow this schedule to help
protect against major repair
expenses resulting from neglect or
inadequate maintenance. It may
also help to maintain the value of
the vehicle if it is sold. It is the
responsibility of the owner to have
all required maintenance performed.
Your dealer has trained technicians
who can perform required
maintenance using genuine
replacement parts. They have
up-to-date tools and equipment for
fast and accurate diagnostics. Many
dealers have extended evening and
Saturday hours, courtesy transportation, and online
scheduling to assist with service
needs.
Your dealer recognizes the
importance of providing
competitively priced maintenance
and repair services. With trained
technicians, the dealer is the place
for routine maintenance such as oil
changes and tire rotations and
additional maintenance items like
tires, brakes, batteries, and wiper
blades.
{ CautionDamage caused by improper
maintenance can lead to costly
repairs and may not be covered
by the vehicle warranty.
Maintenance intervals, checks,
inspections, recommended fluids,
and lubricants are important to
keep the vehicle in good working
condition.

Black plate (3,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Service and Maintenance 11-3
Maintenance
Schedule Owner Checks and Services At Each Fuel Stop .
Check the engine oil level. See
Engine Oil on page 10-8 .
Once a Month .
Check the tire inflation
pressures. See Tire Pressure on
page 10-59 ..
Inspect the tires for wear. See
Tire Inspection on page 10-65 ..
Check the windshield washer
fluid level. See Washer Fluid on
page 10-25 .
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 on
page 10-11 .
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 on page 10-65 . .
Check engine oil level and oil
life percentage. If needed,
change engine oil and filter, and
reset oil life system. See Engine
Oil on page 10-8 and Engine Oil
Life System on page 10-11 . .
Check engine coolant level. See
Engine Coolant on page 10-18 . .
Check windshield washer fluid
level. See Washer Fluid on
page 10-25 .

Black plate (6,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
11-6 Service and Maintenance Footnotes — Maintenance
Schedule Additional Required
Services — Normal
(1) Or every two years, whichever
comes first. 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. (2) Check all fuel and vapor lines
and hoses for proper hook-up,
routing, and condition.
(3) Or every four years, whichever
comes first.
(4) Or every five years, whichever
comes first. See Cooling System on
page 10-17 . (5) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage;
replace, if needed.
(6) Or every three years, whichever
comes first.

Black plate (8,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
11-8 Service and Maintenance Footnotes — Maintenance
Schedule Additional Required
Services — Severe
(1) Or every two years, whichever
comes first. 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.
(2) Check all fuel and vapor lines
and hoses for proper hook-up,
routing, and condition.
(3) Or every four years, whichever
comes first.
(4) Do not directly power wash the
transfer case output seals. High
pressure water can overcome the
seals and contaminate the transfer
case fluid. Contaminated fluid will
decrease the life of the transfer
case and should be replaced. (5) Extreme service. For vehicles
mainly driven off-road in four-wheel
drive or used in farming, mining,
forestry, Department of Natural
Resources (DNR), or snow plowing.
(6) Or every five years, whichever
comes first. See Cooling System on
page 10-17 .
(7) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage;
replace, if needed.
(8) Or every three years, whichever
comes first. Special Application
Services .
Severe Commercial Use
Vehicles Only: Lubricate chassis
components every 5 000 km/
3,000 mi. .
Have underbody flushing service
performed. See "Underbody
Maintenance" in Exterior Care
on page 10-96 .