fluid GMC SIERRA 2015 Owner's Guide

Black plate (27,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-27
proper sequence to torque
specifications inCapacities and
Specifications on page 12-2.
Brake linings should always be
replaced as complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal
does not return to normal height,
or if there is a rapid increase in
pedal travel. This could be a sign
that brake service might be
required.
Brake Adjustment
Every time the brakes are applied,
with or without the vehicle moving,
the brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is
complex. Its many parts have to be
of top quality and work well together
if the vehicle is to have really good
braking. The vehicle was designed
and tested with top-quality brake
parts. When parts of the braking
system are replaced, be sure to get new, approved replacement parts.
If this is not done, the brakes might
not work properly. For example,
installing disc brake pads that are
wrong for the vehicle, can change
the balance between the front and
rear brakes
—for the worse. The
braking performance expected can
change in many other ways if the
wrong replacement brake parts are
installed.
Brake Fluid
The brake master cylinder reservoir
is filled with DOT 3 brake fluid. See
Engine Compartment Overview on
page 10-5 for the location of the
reservoir. There are only two reasons why the
brake fluid level in the reservoir
might go down:
.The brake fluid level goes down
because of normal brake lining
wear. When new linings are
installed, the fluid level goes
back up.
.A fluid leak in the brake
hydraulic system can also cause
a low fluid level. Have the brake
hydraulic system fixed, since a
leak means that sooner or later
the brakes will not work well.
Do not top off the brake fluid.
Adding fluid does not correct a leak.
If fluid is added when the linings are
worn, there will be too much fluid
when new brake linings are
installed. Add or remove brake fluid,
as necessary, only when work is
done on the brake hydraulic system.

Black plate (28,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-28 Vehicle Care
{Warning
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You
or others could be burned, and
the vehicle could be damaged.
Add brake fluid only when work is
done on the brake hydraulic
system. See“Checking Brake
Fluid” in this section.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning
Light on page 5-21.
Refer to the Maintenance Schedule
to determine when to check the
brake fluid. See Maintenance
Schedule on page 11-3.
Checking Brake Fluid
Check brake fluid by looking at the
brake fluid reservoir. See Engine
Compartment Overview on
page 10-5.
The fluid level should be above
MIN. If it is not, have the brake
hydraulic system checked to see if
there is a leak.
After work is done on the brake
hydraulic system, make sure the
level is above MIN but not over the
MAX mark.
What to Add
Use only new DOT 3 brake fluid
from a sealed container. See
Recommended Fluids and
Lubricants on page 11-12. Always clean the brake fluid
reservoir cap and the area around
the cap before removing it. This
helps keep dirt from entering the
reservoir.
{Warning
With the wrong kind of fluid in the
brake hydraulic system, the
brakes might not work well. This
could cause a crash. Always use
the proper brake fluid.
{Caution
.Using the wrong fluid can
badly damage brake
hydraulic system parts. For
example, just a few drops of
mineral-based oil, such as
engine oil, in the brake
hydraulic system can damage
brake hydraulic system parts
so badly that they will have to
(Continued)

Black plate (29,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-29
Caution (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 10-5for battery location.
{Warning
Battery 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
{Warning
Batteries 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 (30,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-30 Vehicle Care
To get an accurate reading, the
vehicle should be on a level
surface.
If the level is below the bottom of
the fill plug (1) hole, located on the
transfer case, some lubricant will
need to be added. Add enough
lubricant to raise the level to the
bottom of the fill plug (1) hole. Use
care not to overtighten the plug.
When to Change Lubricant
Refer toMaintenance Schedule on
page 11-3 to determine how often to
change the lubricant.
What to Use
Refer to Recommended Fluids and
Lubricants on page 11-12 to
determine what kind of lubricant
to use.Front Axle
When to Check and Change
Lubricant
It is not necessary to regularly
check front axle fluid unless a leak
is suspected, or an unusual noise is
heard. A fluid loss could indicate a
problem. Have it inspected and
repaired.
How to Check Lubricant
To get an accurate reading, the
vehicle should be on a level
surface.
1500 Series
1. Fill Plug
2. Drain Plug

Black plate (31,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-31
All Except 1500 Series
1. Fill Plug
2. Drain Plug
.When the differential is cold, add
enough lubricant to raise the
level from 0 mm (0 in) to 3.2 mm
(1/8 in) below the fill
plug (1) hole.
.When the differential is at
operating temperature (warm),
add enough lubricant to raise the
level to the bottom of the fill
plug (1) hole.What to Use
Refer to
Recommended Fluids and
Lubricants on page 11-12 to
determine what kind of lubricant
to use.
Rear Axle
When to Check Lubricant
It is not necessary to regularly
check rear axle fluid unless a leak is
suspected or an unusual noise is
heard. A fluid loss could indicate a
problem. Have it inspected and
repaired.
All axle assemblies are filled by
volume of fluid during production.
They are not filled to reach a certain
level. When checking the fluid level
on any axle, variations in the
readings can be caused by factory
fill differences between the minimum
and the maximum fluid volume. Also, if a vehicle has just been
driven before checking the fluid
level, it may appear lower than
normal because fluid has traveled
out along the axle tubes and has
not drained back to the sump area.
Therefore, a reading taken
five minutes after the vehicle has
been driven will appear to have a
lower fluid level than a vehicle that
has been stationary for an hour or
two. Remember that the rear axle
assembly must be supported to get
a true reading.

Black plate (32,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-32 Vehicle Care
How to Check Lubricant
2500HD with 6.0L
All Other Series and EnginesTo get an accurate reading, the
vehicle should be on a level
surface.
.For 6.2L 1500 Series
applications, the proper level is
from 15 mm to 40 mm (0.6 in to
1.6 in) below the bottom of the
fill plug hole, located on the rear
axle. Add only enough fluid to
reach the proper level.
.For all 6.0L 2500HD Series
applications, the proper level is
from 0 mm to 13 mm (0 to 0.5 in)
below the bottom of the fill plug
hole, located on the rear axle.
Add only enough fluid to reach
the proper level.
.For all 6.6L Duramax Diesel
2500HD Series applications and
all 3500 Series applications, the
proper level is from 17 mm to
21 mm (0.6 in to 0.8 in) below
the bottom of the fill plug hole,
located on the rear axle. Add
only enough fluid to reach the
proper level.
What to Use
Refer to
Recommended Fluids and
Lubricants on page 11-12 to
determine what kind of lubricant
to use.
Noise Control System
The following information relates to
compliance with federal noise
emission standards for vehicles with
a Gross Vehicle Weight Rating
(GVWR) of more than 4 536 kg
(10,000 lb). The noise control
system warranty is given in your
warranty manual.
These standards apply only to
vehicles sold in the United States.
Federal law prohibits the following
acts or the causing thereof:
1. The removal or rendering
inoperative by any person, other
than for purposes of
maintenance, repair or
replacement, of any device or
element of design incorporated
into any new vehicle for the

Black plate (89,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-89
{Warning
Using an open flame near a
battery can cause battery gas to
explode. People have been hurt
doing this, and some have been
blinded. Use a flashlight if you
need more light.
Be sure the battery has enough
water. You do not need to add
water to the battery installed in
your new vehicle. But if a battery
has filler caps, be sure the right
amount of fluid is there. If it is low,
add water to take care of that
first. If you do not, explosive gas
could be present.
Battery fluid contains acid that
can burn you. Do not get it on
you. If you accidentally get it in
your eyes or on your skin, flush
the place with water and get
medical help immediately.
{Warning
Fans or other moving engine
parts can injure you badly. Keep
your hands away from moving
parts once the engine is running.
6. Check that the jumper cables do not have loose or missing
insulation. If they do, you could
get a shock. The vehicles could
be damaged too.
Before you connect the cables,
here are some basic things you
should know. Positive (+) will go
to positive (+) or to a remote
positive (+) terminal if the
vehicle has one. Negative (−)
will go to a heavy, unpainted
metal engine part or to a remote
negative (−) terminal if the
vehicle has one.
Do not connect positive (+) to
negative (−) or you will get a
short that would damage the
battery and maybe other parts too. And do not connect the
negative (−) cable to the
negative (−) terminal on the
dead battery because this can
cause sparks.
5.3L Shown, 6.0L, 6.2L, and 6.6L
Similar
7. Connect the red positive (+) cable to the positive (+) terminal
of the vehicle with the dead
battery.
8. Do not let the other end touch metal. Connect it to the
positive (+) terminal of the good

Black plate (96,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
10-96 Vehicle Care
2. Set the parking brake. SeeParking Brake on page 9-47.
3. Put the transmission in P (Park).
4. Secure the vehicle to the dolly following the manufacturer's
instructions.
5. Use a clamping device designed for towing to ensure that the
front wheels are locked into the
straight position.
6. Turn the ignition to LOCK/OFF.
Four-Wheel-Drive Vehicles
{Warning
Shifting a four-wheel-drive
vehicle's transfer case into
N (Neutral) can cause the vehicle
to roll even if the transmission is
in P (Park). You or others could
be injured. Set the parking brake
before shifting the transfer case
to N (Neutral). To dolly tow a four-wheel-drive
vehicle from the rear:
1. Drive the rear wheels onto the
dolly.
2. Set the parking brake. See Parking Brake on page 9-47.
3. Put the transmission in P (Park).
4. Secure the vehicle to the dolly following the manufacturer's
instructions.
5. Use a clamping device designed for towing to ensure that the
front wheels are locked into the
straight position.
6. Shift the transfer case to N (Neutral). See “Shifting into
Neutral” underFour-Wheel Drive
on page 9-40 for the proper
procedure.
7. Turn the ignition to LOCK/OFF.
Appearance Care
Exterior Care
Locks
Locks are lubricated at the factory.
Use a de-icing agent only when
absolutely necessary, and have the
locks greased after using. See
Recommended Fluids and
Lubricants on page 11-12.
Washing the Vehicle
To preserve the vehicle's finish,
wash it often and out of direct
sunlight.
{Caution
Do not use petroleum-based,
acidic, or abrasive cleaning
agents as they can damage the
vehicle's paint, metal, or plastic
parts. If damage occurs, it would
not be covered by the vehicle
warranty. Approved cleaning (Continued)

Black plate (99,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Vehicle Care 10-99
emblems, 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.
{Caution
Failure to clean lamps properly
can cause damage to the lamp
cover that would not be covered
by the vehicle warranty.
{Caution
Using 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 (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 ApplicationServices . . . . . . . . . . . . . . . . . . . . 11-8
Additional Maintenance
and Care
Additional Maintenanceand Care . . . . . . . . . . . . . . . . . . . 11-9
Recommended Fluids,
Lubricants, and Parts
Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . 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.
{Caution
Damage 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.