2010 GMC SIERRA DENALI open hood

Adjustable Throttle and Brake Pedal
On vehicles with this feature, you can change the
position of the throttle and brake pedals.
No adjustment to the pedals can be made when the
vehicle is in R (Reverse) or while using the cruise
control.
The switch used to adjust
the pedals is located on
the instrument panel
below the climate control
system.
Press the arrow at the bottom of the switch to move the
pedals closer to your body. Press the arrow at the top of
the switch to move the pedals away from your body.
Before you start driving, fully press the brake pedal to
confirm the adjustment is right for you. While driving,
make only small adjustments. The vehicle may have a memory function which lets
pedal settings be saved and recalled. See
Memory
Features
on page 2‑6for more information.
Engine Coolant Heater
The engine coolant heater can provide easier starting
and better fuel economy during engine warm-up in cold
weather conditions at or below −18°C (0°F). Vehicles
with an engine heater should be plugged in at least four
hours before starting. An internal thermostat in the
plug-end of the cord may exist which will prevent engine
coolant heater operation at temperatures above
−18°C (0°F).
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The cord is secured to the Engine Compartment Fuse
Block with a clip. Carefully remove the wire tie
which secures the electrical cord. Do not cut the
electrical cord.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
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Outlet Adjustment
Use the air outlets located in the center and on the side
of the instrument panel to direct the airflow. Use the
thumbwheels near the air outlets to open or close off
the airflow.
Operation Tips
.Clear away any ice, snow, or leaves from air inlets
at the base of the windshield that could block the
flow of air into the vehicle.
.Keep the path under the front seats clear of
objects to help circulate the air inside of the vehicle
more effectively.
.Use of non‐GM approved hood deflectors can
adversely affect the performance of the system.
Check with your dealer/retailer before adding
equipment to the outside of the vehicle.
Warning Lights, Gages, and
Indicators
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause an
expensive repair or replacement. Paying attention to the
warning lights and gages could prevent injury.
Warning lights come on when there might be or there is
a problem with one of the vehicle's functions. Some
warning lights come on briefly when the engine is
started to indicate they are working.
Gages can indicate when there might be or there is a
problem with one of the vehicle's functions. Often gages
and warning lights work together to indicate a problem
with the vehicle.
When one of the warning lights comes on and stays on
while driving, or when one of the gages shows there
could be a problem, check the section that explains
what to do. Follow this manual's advice. Waiting to do
repairs can be costly and even dangerous.
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ENGINE POWER IS REDUCED
This message displays and a chime sounds when the
cooling system temperature gets too hot and the engine
further enters the engine coolant protection mode. See
Engine Overheating
on page 6‑34for further
information.
This message also displays when the vehicle's engine
power is reduced. Reduced engine power can affect the
vehicle's ability to accelerate. If this message is on, but
there is no reduction in performance, proceed to your
destination. The performance may be reduced the next
time the vehicle is driven. The vehicle may be driven at
a reduced speed while this message is on, but
acceleration and speed may be reduced. Anytime this
message stays on, the vehicle should be taken to your
dealer/retailer for service as soon as possible.
FUEL LEVEL LOW
This message displays and a chime sounds if the fuel
level is low. Refuel as soon as possible. See Fuel Gage
on page 4‑43andFuelon page 6‑6for more
information.
HOOD OPEN
This message displays and a chime sounds if the hood
is not fully closed. Stop and turn off the vehicle, check
the hood for obstructions, and close the hood again.
Check to see if the message still appears on the DIC.
ICE POSSIBLE DRIVE WITH CARE
This message displays when ice conditions are
possible.
LEFT REAR DOOR OPEN
This message displays and a chime sounds if the driver
side rear door is not fully closed and the vehicle is
shifted out of P (Park). Stop and turn off the vehicle,
check the door for obstructions, and close the door
again. Check to see if the message still appears on
the DIC.
OIL PRESSURE LOW STOP ENGINE
Notice: If you drive your vehicle while the engine oil
pressure is low, severe engine damage may occur.
If a low oil pressure warning appears on the Driver
Information Center (DIC), stop the vehicle as soon
as possible. Do not drive the vehicle until the cause
of the low oil pressure is corrected. See Engine Oil
on page 6‑18for more information.
This message displays if low oil pressure levels occur.
Stop the vehicle as soon as safely possible and do not
operate it until the cause of the low oil pressure has
been corrected. Check the oil as soon as possible and
have your vehicle serviced by your dealer/retailer. See
Engine Oil on page 6‑18.
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Gasoline Octane
Use premium unleaded gasoline with a posted octane
rating of 91 or higher. You can also use regular
unleaded gasoline rated at 87 octane or higher, but the
vehicle's acceleration could be slightly reduced, and a
slight audible knocking noise, commonly referred to as
spark knock, might be heard. If the octane is less than
87, you might notice a heavy knocking noise when you
drive. If this occurs, use a gasoline rated at 87 octane
or higher as soon as possible. Otherwise, you could
damage the engine. If heavy knocking is heard when
using gasoline rated at 87 octane or higher, the engine
needs service.
Gasoline Specifications
At a minimum, gasoline should meet ASTM
specification D 4814 in the United States or
CAN/CGSB‐3.5 or 3.511 in Canada. Some gasolines
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT).
We recommend against the use of gasolines containing
MMT. SeeAdditives
on page 6‑8for additional
information.
California Fuel
If the vehicle is certified to meet California Emissions
Standards, it is designed to operate on fuels that meet
California specifications. See the underhood emission
control label. If this fuel is not available in states
adopting California emissions standards, the vehicle will
operate satisfactorily on fuels meeting federal
specifications, but emission control system performance
might be affected. The malfunction indicator lamp could
turn on and the vehicle might fail a smog‐check test.
See Malfunction Indicator Lamp
on page 4‑38. If this
occurs, return to your authorized dealer/retailer for
diagnosis. If it is determined that the condition is caused
by the type of fuel used, repairs might not be covered
by the vehicle warranty.
6-7

Checking Things Under
the Hood
{WARNING:
An electric fan under the hood can start up and
injure you even when the engine is not running.
Keep hands, clothing, and tools away from any
underhood electric fan.
{WARNING:
Things that burn can get on hot engine parts and
start a fire. These include liquids like fuel, oil,
coolant, brake fluid, windshield washer and other
fluids, and plastic or rubber. You or others could
be burned. Be careful not to drop or spill things
that will burn onto a hot engine.
Hood Release
To open the hood:
1. Pull the handle withthis symbol on it. It is
located inside the
vehicle to the left of the
brake pedal.
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2. Then go to the front of the vehicle and locate thesecondary hood release. This is located under the
hood, near the center of the grille. 3. Push the secondary hood release to the right.
4. Lift the hood.
Before closing the hood, be sure all the filler caps
are on properly. Then bring the hood from full open
to within 6 inches (152 mm) from the closed
position, pause, then push the front center of the
hood with a swift, firm motion to fully close
the hood.
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Engine Compartment Overview
When you open the hood on the 6.2L engine this is what you will see:
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You may decide not to lift the hood when this warning
appears, but instead get service help right away. See
Roadside Assistance Program on page 8‑7.
If you do decide 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 your warranty.
See Overheated Engine Protection Operating Mode
on page 6‑37for 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 6‑37for 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.
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.
See Overheated Engine Protection Operating
Mode
on page 6‑37for information on driving to
a safe place in an emergency.
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