2011 GMC SIERRA check engine

Black plate (23,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-23
Notice:If extra inhibitors
and/or additives are used in
the vehicle cooling system,
the vehicle could be damaged.
Use only the proper mixture of
the engine coolant listed in this
manual for the cooling system.
See Recommended Fluids and
Lubricants on page 11‑8 for more
information.
Never dispose of engine coolant
by putting it in the trash, pouring
it on the ground, or into sewers,
streams, or bodies of water.
Have the coolant changed by an
authorized service center, familiar
with legal requirements regarding
used coolant disposal. This will help
protect the environment and your
health.Checking Coolant
The coolant surge tank is located
in the engine compartment on the
passenger side of the vehicle.
See Engine Compartment Overview
on page 10‑6 for more information
on location.
The vehicle must be on a level
surface when checking the coolant
level.
Check to see if coolant is visible
in the coolant surge tank. If the
coolant inside the coolant surge
tank is boiling, do not do anything
else until it cools down. If coolant is
visible but the coolant level is not at
or above the FULL COLD mark, add
a 50/50 mixture of clean, drinkable
water and DEX-COOL coolant at the
coolant surge tank, but be sure the
cooling system is cool before this
is done.
The coolant level should be at or
above the FULL COLD mark. If it is
not, there may be a leak in the
cooling system.

Black plate (26,1)GMC Sierra Owner Manual - 2011
10-26 Vehicle Care
If the decision is made not to lift the
hood when this warning appears,
get service help right away.
SeeRoadside Assistance Program
(U.S. and Canada) on page 13‑8
or Roadside Assistance Program
(Mexico) on page 13‑10.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
Then check to see if the engine
cooling fans are running. If the
engine is overheating, both fans
should be running. If they are not,
do not continue to run the engine
and have the vehicle serviced.
Notice: Engine damage from
running your engine without
coolant is not covered by the
vehicle warranty. See Overheated
Engine Protection Operating
Mode for information on driving
to a safe place in an emergency. Notice:
If the engine catches fire
while driving with no coolant, the
vehicle can be badly damaged.
The costly repairs would not
be covered by the vehicle
warranty. See Overheated Engine
Protection Operating Mode on
page 10‑28 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 10‑28 for information on
driving to a safe place in an
emergency.

Black plate (29,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-29
Power Steering Fluid
SeeEngine Compartment Overview
on page 10‑6 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 11‑8. 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 11‑8.
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 (32,1)GMC Sierra Owner Manual - 2011
10-32 Vehicle Care
Brake Fluid
The brake master cylinder reservoir
is filled with DOT 3 brake fluid.
SeeEngine Compartment Overview
on page 10‑6 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.
{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, (Continued)
WARNING (Continued)
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 5‑27.
Refer to the Maintenance Schedule
to determine when to check the
brake fluid. See Scheduled
Maintenance on page 11‑2.

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 (34,1)GMC Sierra Owner Manual - 2011
10-34 Vehicle Care
Battery
If the vehicle is a Hybrid, see
the Hybrid Supplement for more
information.
This vehicle has a maintenance free
battery (or batteries). Refer to the
replacement number on the original
battery label when a new battery is
needed. SeeEngine Compartment
Overview on page 10‑6 for battery
location.
{DANGER
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 10‑98 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 Scheduled Maintenance on
page 11‑2 to determine when to
check the lubricant.
How to Check Lubricant
Electric Shift Transfer Case
A. Fill Plug
B. Drain Plug

Black plate (37,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-37
What to Use
Refer toRecommended Fluids
and Lubricants on page 11‑8 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.
How to Check Lubricant
2500HD with 6.0 L
All Other Series and Engines
To get an accurate reading, the
vehicle should be on a level
surface.
.For all 4.3 L, 4.8 L and 5.3 L
1500 Series applications,
the proper level is 1.0 mm to
19.0 mm (0.04 in to 0.7 in)
below the bottom of the fill
hole, located on the rear axle.
Add only enough fluid to reach
the proper level.

Black plate (39,1)GMC Sierra Owner Manual - 2011
Vehicle Care 10-39
Among those acts presumed to
constitute tampering are the acts
listed below.
Insulation:
Removal of the noise shields or any
underhood insulation.
Engine:
Removal or rendering engine speed
governor, if the vehicle has one,
inoperative so as to allow engine
speed to exceed manufacturer
specifications.
Fan and Drive:
.Removal of fan clutch, if the
vehicle has one, or rendering
clutch inoperative.
.Removal of the fan shroud, if the
vehicle has one.
Air Intake:
.Removal of the air cleaner
silencer.
.Modification of the air cleaner. Exhaust:
.Removal of the muffler and/or
resonator.
.Removal of the exhaust pipes
and exhaust pipe clamps.
Starter Switch Check
{WARNING
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. 2. Firmly apply both the parking
brake and the regular brake.
See Parking Brake on
page 9‑69.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.