
Black plate (13,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-13
Automatic
Transmission Fluid
(4-Speed Transmission)
When to Check and Change
Automatic Transmission Fluid
A good time to check the automatic
transmission fluid level is when the
engine oil is changed.
Change the fluid and filter at
the intervals listed inScheduled
Maintenance on page 11‑2 and be
sure to use the transmission fluid
listed in Recommended Fluids and
Lubricants on page 11‑8.
How to Check Automatic
Transmission Fluid
Because this operation can be a
little difficult, it may be best to have
this done at the dealer service
department.
If not taken to the dealer, be sure to
follow all the instructions here or a
false reading on the dipstick could
result.
Notice: Too much or too
little fluid can damage the
transmission. Too much can
mean that some of the fluid could
come out and fall on hot engine
parts or exhaust system parts,
starting a fire. Too little fluid
could cause the transmission
to overheat. Be sure to get an
accurate reading if checking
the transmission fluid. Wait at least 30 minutes before
checking the transmission fluid
level if you have been driving:.When outside temperatures are
above 32°C (90°F).
.At high speed for quite a while.
.In heavy traffic
—especially in
hot weather.
.While pulling a trailer.
To get the right reading, the fluid
should be at normal operating
temperature, which is 82°C to 93°C
(180°F to 200°F).
Get the vehicle warmed up by
driving about 24 km (15 miles) when
outside temperatures are above
10°C (50°F). If it is colder than 10°C
(50°F), drive the vehicle in 3 (Third)
until the engine temperature gauge
moves and then remains steady for
10 minutes.

Black plate (27,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-27
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; seeTrailer Towing
on page 9‑95. 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).
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.

Black plate (28,1)GMC Sierra Owner Manual - 2011
10-28 Vehicle Care
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 10‑7.
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,
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.

Black plate (51,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-51
FusesUsage
1 Right Trailer
Stop/Turn Lamp
2 Electronic
Suspension
Control, Automatic
Level Control
Exhaust Fuses
Usage
3 Left Trailer
Stop/Turn Lamp
4 Engine Controls
5 Engine Control
Module, Throttle
Control Fuses
Usage
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)
14 Transmission
Control Module
(Battery)
15 Vehicle Back-up
Lamps

Black plate (52,1)GMC Sierra Owner Manual - 2011
10-52 Vehicle Care
FusesUsage
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)
25 Trailer Park Lamps
26 Driver Side Park
Lamps
27 Passenger Side
Park Lamps Fuses
Usage
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
36 Windshield Wiper
37 SEO B2 Upfitter
Usage (Battery)
38 Electric Adjustable
Pedals Fuses
Usage
39 Climate Controls
(Battery)
40 Airbag System
(Ignition)
41 Amplifier
42 Audio System
43 Miscellaneous
(Ignition),
Cruise Control
44 Not Used
45 Airbag System
(Battery)
46 Instrument Panel
Cluster
47 Power Take-Off
48 Auxiliary Climate
Control (Ignition)
49 Center
High-Mounted
Stoplamp (CHMSL)
50 Rear Defogger

Black plate (53,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-53
FusesUsage
51 Heated Mirrors
52 SEO B1 Upfitter
Usage (Battery)
53 Cigarette Lighter,
Auxiliary Power
Outlet
54 SEO Upfitter
Usage
55 Climate Controls
(Ignition)
56 Engine Control
Module, Secondary
Fuel Pump
(Ignition)
J-Case Fuses Usage
57 Cooling Fan 1
58 Not Used
59 Heavy Duty
Antilock Brake
System J-Case
Fuses Usage
60 Cooling Fan 2
61 Antilock Brake
System 1
62 Starter
63 Stud 2
(Trailer Brakes)
64 Left Bussed
Electrical Center 1
65 Not Used
66 Heated Windshield
Washer System
67 Transfer Case
68 Stud 1 (Trailer
Connector
Battery Power)
(Optional - 40A
Fuse Required)
69 Mid-Bussed
Electrical Center 1
70 Climate Control
Blower J-Case
Fuses Usage
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
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

Black plate (103,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-103
Towing
Towing the Vehicle
Notice:To avoid damage,
the disabled vehicle should be
towed with all four wheels off
the ground. Care must be taken
with vehicles that have low
ground clearance and/or special
equipment. Always flatbed on a
car carrier.
Consult your dealer or a
professional towing service if the
disabled vehicle must be towed.
See Roadside Assistance Program
(U.S. and Canada) on page 13‑8
or Roadside Assistance Program
(Mexico) on page 13‑10.
To tow the vehicle behind another
vehicle for recreational purposes,
such as behind a motor home, see
“Recreational Vehicle Towing” in this
section.
Recreational Vehicle
Towing
Recreational vehicle towing means
towing the vehicle behind another
vehicle, such as a motor home.
The two most common types of
recreational vehicle towing are
known as dinghy towing and dolly
towing. Dinghy towing is towing the
vehicle with all four wheels on the
ground. Dolly towing is towing the
vehicle with two wheels on the
ground and two wheels up on a
device known as a dolly.
Here are some important things to
consider before recreational vehicle
towing:
.What is the towing capacity
of the towing vehicle?
Be sure to read the tow
vehicle manufacturer's
recommendations.
.What is the distance that will be
travelled? Some vehicles have
restrictions on how far and how
long they can tow.
.Is the proper towing equipment
going to be used? See your
dealer or trailering professional
for additional advice and
equipment recommendations.
.Is the vehicle ready to be
towed? Just as preparing the
vehicle for a long trip, make sure
the vehicle is prepared to be
towed.

Black plate (6,1)GMC Sierra Owner Manual - 2011
11-6 Service and Maintenance
First Engine Oil Change After
Every 40 000 km/25,000 Miles
.Four‐wheel drive only: Transfer
case fluid change (extreme duty
service) for vehicles mainly
driven off‐road in four‐wheel
drive. Vehicles used for farming,
mining, forestry, Department of
Natural Resources (DNR), and
snow plowing occupations meet
this definition. Check vent hose
at transfer case for kinks and
proper installation. Check to be
sure vent hose is unobstructed,
clear, and free of debris. During
any maintenance, if a power
washer is used to clean mud
and dirt from the underbody,
care should be taken to not
directly spray 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.First Engine Oil Change After
Every 80 000 km/50,000 Miles.Engine air cleaner filter
replacement. See
Engine Air
Cleaner/Filter on page 10‑19.
.Automatic transmission fluid
change (severe service) for
vehicles with Gross Vehicle
Weight Rating (GVWR) over
3 901 kg (8,600 lbs) or mainly
driven in heavy city traffic in hot
weather, in hilly or mountainous
terrain, when frequently towing
a trailer, or used for taxi,
police, or delivery service.
See Automatic Transmission
Fluid (4-Speed Transmission) on
page 10‑13 orAutomatic
Transmission Fluid (6-Speed
Transmission) on page 10‑16.
.Four‐wheel drive only: Transfer
case fluid change (severe
service) for vehicles mainly
driven when frequently towing
a trailer, or used for taxi, police,
or delivery service. Check
vent hose at transfer case for
kinks and proper installation.
Check to be sure vent hose is
unobstructed, clear, and free of
debris. During any maintenance,
if a power washer is used to
clean mud and dirt from the
underbody, care should be taken
to not directly spray 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.