
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 (33,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-33
Checking Brake Fluid
Check brake fluid by looking at the
brake fluid reservoir. SeeEngine
Compartment Overview on
page 10‑6.
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 the 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 11‑8.
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. Notice:
.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 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.

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 (2,1)GMC Sierra Owner Manual - 2011
11-2 Service and Maintenance
{WARNING
Performing maintenance work can
be dangerous. Some jobs can
cause serious injury. Perform
maintenance work only if you
have the required know-how and
the proper tools and equipment.
If in doubt, see your dealer to
have a qualified technician do
the work. SeeDoing Your Own
Service Work on page 10‑4.
At your dealer, you can be
certain that you will receive the
highest level of service available.
Your dealer has specially trained
service technicians, uses genuine
replacement parts, as well as,
up‐to‐date tools and equipment
to ensure fast and accurate
diagnostics. The proper replacement parts,
fluids, and lubricants to use are
listed in
Recommended Fluids
and Lubricants on page 11‑8 and
Maintenance Replacement Parts on
page 11‑11. We recommend the use
of genuine parts from your dealer.
Rotation of New Tires
To maintain ride, handling, and
performance of the vehicle, it is
important that the first rotation
service for new tires be performed.
Tires should be rotated every
12 000 km/7,500 miles. See Tire
Rotation on page 10‑73.
Scheduled
Maintenance
When the Change Engine Oil
Soon Message Displays
Change engine oil and filter.
See Engine Oil on page 10‑7.
An Emission Control Service.
When the CHANGE ENGINE OIL
SOON message displays in the
Driver Information Center (DIC),
service is required for the vehicle
as soon as possible, within the next
1 000 km/600 miles. If driving under
the best conditions, the engine oil
life system might not indicate the
need for vehicle service for more
than a year. The engine oil and filter
must be changed at least once a
year and the oil life system must
be reset. Your dealer has trained
service technicians who will perform
this work and reset the system.

Black plate (3,1)GMC Sierra Owner Manual - 2011
Service and Maintenance 11-3
If the engine oil life system is reset
accidentally, service the vehicle
within 5 000 km/3,000 miles since
the last service. Reset the oil life
system whenever the oil is changed.
SeeEngine Oil Life System on
page 10‑11.
Every Engine Oil Change
.Change engine oil and
filter. Reset oil life system.
See Engine Oil on page 10‑7
and Engine Oil Life System on
page 10‑11. An Emission Control
Service.
.Engine coolant level check.
See Engine Coolant on
page 10‑22.
.Engine cooling system
inspection. Visual inspection
of hoses, pipes, fittings, and
clamps and replacement,
if needed.
.Windshield washer fluid level
check. See Washer Fluid on
page 10‑29.
.Windshield wiper blade
inspection for wear, cracking,
or contamination and windshield
and wiper blade cleaning,
if contaminated. See Exterior
Care on page 10‑108. Worn
or damaged wiper blade
replacement. See Wiper Blade
Replacement on page 10‑41.
.Tire inflation pressures
check. See Tire Pressure on
page 10‑66.
.Tire wear inspection. See Tire
Inspection on page 10‑73.
.Rotate tires if necessary.
See Tire Rotation on
page 10‑73.
.Fluids visual leak check
(or every 12 months, whichever
occurs first). A leak in any
system must be repaired and
the fluid level checked.
.Engine air cleaner filter
inspection. See Engine Air
Cleaner/Filter on page 10‑19.
.Brake system inspection
(or every 12 months, whichever
occurs first).
.For vehicles with Allison
Transmission®only: At the first
engine oil change only, replace
external transmission filter.
.Steering and suspension
inspection. Visual inspection
for damaged, loose, or missing
parts or signs of wear.

Black plate (5,1)GMC Sierra Owner Manual - 2011
Service and Maintenance 11-5
Additional Required Services
At the First 160 km/100 Miles,
1 600 km/1,000 Miles, and
10 000 km/6,000 Miles
.For vehicles with dual
wheels: Check dual wheel
nut torque. For proper
torque, seeCapacities and
Specifications on page 12‑2.
Every 12 000 km/7,500 Miles
.Rotate tires. Tires should
be rotated every 12 000 km/
7,500 miles. See Tire Rotation
on page 10‑73.
At Each Fuel Stop
.Engine oil level check.
See Engine Oil on page 10‑7.
.Engine coolant level check.
SeeEngine Coolant on
page 10‑22.
.Windshield washer fluid level
check. See Washer Fluid on
page 10‑29. Once a Month
.Tire inflation pressures
check. See
Tire Pressure on
page 10‑66.
.Tire wear inspection. See Tire
Inspection on page 10‑73.
.Sunroof track and seal
inspection, if equipped.
See Sunroof (Extended Cab) on
page 2‑21 orSunroof (Crew
Cab) on page 2‑22.
Once a Year
.See Starter Switch Check on
page 10‑39.
.See Automatic Transmission
Shift Lock Control Function
Check on page 10‑40.
.See Ignition Transmission Lock
Check on page 10‑40.
.See Park Brake and P (Park)
Mechanism Check on
page 10‑40.
.Accelerator pedal check for
damage, high effort, or binding.
Replace if needed.
.Underbody flushing service.
.Hood/Decklid/Liftgate/Liftglass
Support Gas Strut Service:
Visually inspect gas strut,
if equipped, for signs of wear,
cracks, or other damage. Check
the hold open ability of the gas
strut. Contact your dealer if
service is required.

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.

Black plate (7,1)GMC Sierra Owner Manual - 2011
Service and Maintenance 11-7
.Evaporative control system
inspection. Check all fuel and
vapor lines and hoses for proper
hook‐up, routing, and condition.
Check that the purge valve,
if the vehicle has one, works
properly. Replace as needed.
An Emission Control Service.
The U.S. Environmental
Protection Agency or the
California Air Resources Board
has determined that the failure
to perform this maintenance
item will not nullify the emission
warranty or limit recall liability
prior to the completion of
the vehicle's useful life.
We, however, urge that all
recommended maintenance
services be performed at the
indicated intervals and the
maintenance be recorded.First Engine Oil Change After
Every 160 000 km/100,000 Miles
.Automatic transmission fluid
change (normal 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 (normal
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.
.Spark plug replacement and
spark plug wires inspection.
An Emission Control Service.
First Engine Oil Change After
Every 240 000 km/150,000 Miles
.Engine cooling system drain,
flush, and refill (or every five
years, whichever occurs first).
See Engine Coolant on
page 10‑22. An Emission
Control Service.
.Engine drive belts inspection
for fraying, excessive cracks,
or obvious damage (or every
10 years, whichever occurs
first). Replace, if needed.