2013 GMC SIERRA air condition

Black plate (15,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Vehicle Care 10-15
4. Check both sides of the dipstickand read the lower level. Repeat
the check procedure to verify the
reading.
5. Safe operating level is within the
HOT cross hatch band on the
dipstick. If the fluid level is not
within the HOT band, and the
transmission temperature is
between 71°C and 93°C (160°F
and 200°F), add or drain fluid as
necessary to bring the level into
the HOT band. If the fluid level is
low, add only enough fluid to
bring the level into the HOT
band. It does not take much
fluid, generally less than 0.5 L
(1 pint). Do not overfill. 6. If the fluid level is in the
acceptable range, push the
dipstick back in all the way, then
flip the handle down to lock the
dipstick in place.
Consistency of Readings
Always check the fluid level at least
twice using the procedure described
previously. Consistency (repeatable
readings) is important to maintaining
proper fluid level. If readings are still
inconsistent, contact the dealer.
Engine Air Cleaner/Filter
If the vehicle has a diesel engine,
see “Pickup Models” under“Engine
Air Cleaner/Filter” in the Duramax
®
Diesel Supplement for the correct
inspection and replacement
procedures.
SeeEngine Compartment Overview
on page 10‑5 for the location of the
engine air cleaner/filter.
When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/filter at the
scheduled maintenance intervals
and replace it at the first oil change
after each 80 000 km (50,000 mi)
interval. See Maintenance Schedule
on page 11‑3 for more information.
If driving on dusty/dirty conditions,
inspect the filter at each engine oil
change.
How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/filter,
remove the engine air cleaner/filter
from the vehicle by following
Steps 1 through 6. When the engine
air cleaner/filter is removed, lightly
shake it to release loose dust and
dirt. If the engine air cleaner/filter
remains covered with dirt, a new
filter is required. Never use
compressed air to clean the filter.

Black plate (21,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Vehicle Care 10-21
Notice:Running the engine
without coolant may cause
damage or a fire. Vehicle damage
would not be covered by the
warranty. See Overheated Engine
Protection Operating Mode on
page 10‑22 for information on
driving to a safe place in an
emergency.
If Steam is Coming from the
Engine Compartment
{WARNING
Steam from an overheated engine
can burn you badly, even if you
just open the hood. Stay away
from the engine if you see or hear
steam coming from it. Turn it off
and get everyone away from the
vehicle until it cools down. Wait
until there is no sign of steam or
coolant before you open
the hood.
(Continued)
WARNING (Continued)
If you keep driving when the
vehicles engine is overheated,
the liquids in it can catch fire. You
or others could be badly burned.
Stop the engine if it overheats,
and get out of the vehicle until the
engine is cool.
SeeOverheated Engine
Protection Operating Mode on
page 10‑22 for information on
driving to a safe place in an
emergency.
If No Steam is Coming from
the Engine Compartment
The ENGINE OVERHEATED STOP
ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message, along with a low coolant
condition, can indicate a serious
problem. If there is an engine overheat
warning, but no steam is seen or
heard, the problem may not be too
serious. Sometimes the engine can
get a little too hot when the vehicle:
.Climbs a long hill on a hot day
.Stops after high-speed driving
.Idles for long periods in traffic
.Tows a trailer; see
Trailer Towing
on page 9‑73.
If the ENGINE OVERHEATED
STOP ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message appears with no sign of
steam, try this for a minute or so:
1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest
fan speed. Open the windows as
necessary.
3. If stopped in a traffic jam, apply the brake, shift to N (Neutral);
otherwise, shift to the highest
gear while driving —D (Drive) or
3 (Third).

Black plate (22,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
10-22 Vehicle Care
If the temperature overheat gauge is
no longer in the overheat zone or an
overheat warning no longer
displays, the vehicle can be driven.
Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
vehicle distance from the vehicle in
front. If the warning does not come
back on, continue to drive normally.
If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is no sign of steam, idle the
engine for five minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down. Also, see“Overheated
Engine Protection Operating Mode”
later in this section.
Overheated Engine
Protection
Operating Mode
If an overheated engine condition
exists and the ENGINE POWER IS
REDUCED message displays, an overheat protection mode which
alternates firing groups of cylinders
helps to prevent engine damage. In
this mode, a loss in power and
engine performance will be noticed.
This operating mode allows the
vehicle to be driven to a safe place
in an emergency. Driving
extended km (mi) and/or towing a
trailer in the overheat protection
mode should be avoided.
Notice:
After driving in the
overheated engine protection
operating mode, to avoid engine
damage, allow the engine to cool
before attempting any repair. The
engine oil will be severely
degraded. Repair the cause of
coolant loss, change the oil and
reset the oil life system. See
Engine Oil on page 10‑6.
Engine Fan
If the vehicle has a clutched engine
cooling fan, when the clutch is
engaged, the fan spins faster to
provide more air to cool the engine. In most everyday driving conditions,
the fan is spinning slower and the
clutch is not fully engaged. This
improves fuel economy and reduces
fan noise. Under heavy vehicle
loading, trailer towing, and/or high
outside temperatures, the fan speed
increases as the clutch more fully
engages, so an increase in fan
noise may be heard. This is normal
and should not be mistaken as the
transmission slipping or making
extra shifts. It is merely the cooling
system functioning properly. The fan
will slow down when additional
cooling is not required and the
clutch disengages.
This fan noise may also be heard
when starting the engine. It will go
away as the fan clutch partially
disengages.
If the vehicle has electric cooling
fans, the fans may be heard
spinning at low speed during most
everyday driving. The fans may turn
off if no cooling is required. Under
heavy vehicle loading, trailer towing,
high outside temperatures,

Black plate (23,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Vehicle Care 10-23
or operation of the air conditioning
system, the fans may change to
high speed and an increase in fan
noise may be heard. This is normal
and indicates that the cooling
system is functioning properly. The
fans will change to low speed when
additional cooling is no longer
required.
Power Steering Fluid
SeeEngine Compartment Overview
on page 10‑5 for reservoir location.
When to Check Power Steering
Fluid
It is not necessary to regularly
check power steering fluid unless
there is a leak suspected in the
system or an unusual noise is heard. A fluid loss in this system
could indicate a problem. Have the
system inspected and repaired.
How to Check Power Steering
Fluid
To check the power steering fluid:
1. Turn the key off and let the
engine compartment cool down.
2. Wipe the cap and the top of the reservoir clean.
3. Unscrew the cap and wipe the dipstick with a clean rag.
4. Replace the cap and completely tighten it.
5. Remove the cap again and look at the fluid level on the dipstick.
The level should be at the FULL
COLD mark. If necessary, add only
enough fluid to bring the level up to
the mark.
What to Use
To determine what kind of fluid to
use, see Recommended Fluids and
Lubricants on page 11‑12. Always
use the proper fluid.
Notice: Use of the incorrect fluid
may damage the vehicle and the
damages may not be covered by
the vehicle's warranty. Always
use the correct fluid listed in
Recommended Fluids and
Lubricants on page 11‑12.
Washer Fluid
What to Use
When windshield washer fluid needs
to be added, be sure to read the
manufacturer's instructions before
use. Use a fluid that has sufficient
protection against freezing in an
area where the temperature may fall
below freezing.

Black plate (41,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Vehicle Care 10-41
FusesUsage
4 Engine Controls
5 Engine Control Module, Throttle
Control
6 Trailer Brake Controller
7 Front Washer
8 Oxygen Sensor
9 Antilock Brakes System 2
10 Trailer Back-up Lamps
11 Driver Side Low-Beam
Headlamp
12 Engine Control Module (Battery)
13 Fuel Injectors, Ignition Coils
(Right Side) Fuses
Usage
14 Transmission Control Module
(Battery)
15 Vehicle Back-up Lamps
16 Passenger Side Low-Beam
Headlamp
17 Air Conditioning Compressor
18 Oxygen Sensors
19 Transmission Controls (Ignition)
20 Fuel Pump
21 Fuel System Control Module
22 Not Used
23 Not Used
24 Fuel Injectors, Ignition Coils
(Left Side) Fuses
Usage
25 Trailer Park Lamps
26 Driver Side Park Lamps
27 Passenger Side Park Lamps
28 Fog Lamps
29 Horn
30 Passenger Side High-Beam
Headlamp
31 Daytime Running Lamps (DRL)
32 Driver Side High-Beam
Headlamp
33 Daytime Running Lamps 2
34 Sunroof
35 Key Ignition System, Theft
Deterrent System

Black plate (43,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Vehicle Care 10-43
J-CaseFuses Usage
68 Stud 1 (Trailer Connector Battery
Power) (Optional -
40A Fuse
Required)
69 Mid-Bussed Electrical Center 1
70 Climate Control Blower
71 Not Used
72 Left Bussed Electrical Center 2
Relays Usage
FAN HI Cooling Fan High Speed
FAN LO Cooling Fan Low Speed
FAN CNTRL Cooling Fan Control Relays Usage
HDLP
LO/HID Low-Beam
Headlamp
FOG LAMP Front Fog Lamps
A/C
CMPRSR Air Conditioning
Compressor
STRTR Starter
PWR/TRN Powertrain
FUEL PMP Fuel Pump
PRK LAMP Parking Lamps
REAR
DEFOG Rear Defogger
RUN/CRNK Switched PowerInstrument Panel Fuse
Block
The instrument panel fuse block
access door is located on the driver
side edge of the instrument panel.
Pull off the cover to access the fuse
block.

Black plate (47,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
Vehicle Care 10-47
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.See
Tire Pressure for
High-Speed Operation on
page 10‑56 for inflation pressure
adjustment for high speed
driving.
20‐Inch Tires
If the vehicle has 20‐inch P275/
55R20 size tires, they are
classified as touring tires and
are designed for on road use.
The low‐profile, wide tread
design is not recommended for
“off‐road” driving or commercial
uses such as snow plowing. See
Off-Road Driving on page 9‑5
and Adding a Snow Plow or
Similar Equipment on
page 9‑101 for additional
information.
Notice: Low‐profile tires are
more susceptible to damage
from road hazards or curb
impact than standard profile
tires. Tire and/or wheel
assembly damage can occur when coming into contact
with road hazards like,
potholes, or sharp edged
objects, or when sliding into a
curb. The warranty does not
cover this type of damage.
Keep tires set to the correct
inflation pressure and, when
possible, avoid contact with
curbs, potholes, and other
road hazards.
All-Season Tires
This vehicle may come with
all-season tires. These tires are
designed to provide good overall
performance on most road surfaces
and weather conditions. Original
equipment tires designed to GM's
specific tire performance criteria
have a TPC specification code
molded onto the sidewall. Original
equipment all-season tires can be
identified by the last two characters
of this TPC code, which will
be
“MS.”

Black plate (52,1)GMC Sierra Owner Manual - 2013 - crc - 8/14/12
10-52 Vehicle Care
Light Truck (LT‐Metric) Tire
(A) Light Truck (LT‐Metric)
Tire
:The United States version
of a metric tire sizing system.
The letters LT as the first two
characters in the tire size mean
a light truck tire engineered to
standards set by the U.S. Tire
and Rim Association.
(B) Tire Width
:The three‐digit
number indicates the tire section
width in millimeters from
sidewall to sidewall.
(C) Aspect Ratio
:A two‐digit
number that indicates the tire
height‐to‐width measurements.
For example, if the tire size
aspect ratio is 75, as shown in
item C of the light truck (LT‐Metric) tire illustration, it
would mean that the tire's
sidewall is 75 percent as high as
it is wide.
(D) Construction Code
:A
letter code is used to indicate
the type of ply construction in
the tire. The letter R means
radial ply construction; the
letter D means diagonal or bias
ply construction; and the letter B
means belted‐bias ply
construction.
(E) Rim Diameter
:Diameter of
the wheel in inches.
(F) Load Range
:Load Range.
(G) Service Description
:The
service description indicates the
load index and speed rating of a
tire. If two numbers are given as
in the example, 120/116, then
this represents the load index for
single versus dual wheel usage (single/dual). The speed rating is
the maximum speed a tire is
certified to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch of
the tire. Air pressure is
expressed in kPa (kilopascal)
or psi (pounds per square inch).
Accessory Weight
:The
combined weight of optional
accessories. Some examples of
optional accessories are
automatic transmission, power
steering, power brakes, power
windows, power seats, and air
conditioning.
Aspect Ratio
:The relationship
of a tire's height to its width.