check engine GMC SIERRA 2009 Owner's Guide

Braking in Emergencies
ABS allows the driver to steer and brake at the same
time. In many emergencies, steering can help more than
even the very best braking.
Brake Assist (Except With 4.3L V6 Engine)
If this vehicle has StabiliTrak®, it also has a Brake
Assist feature designed to assist the driver in stopping
or decreasing vehicle speed in emergency driving
conditions. This feature uses the stability system
hydraulic brake control module to supplement the
power brake system under conditions where the driver
has quickly and forcefully applied the brake pedal in
an attempt to quickly stop or slow down the vehicle.
The stability system hydraulic brake control module
increases brake pressure at each corner of the vehicle
until the ABS activates. Minor brake pedal pulsations
or pedal movement during this time is normal and
the driver should continue to apply the brake pedal as
the driving situation dictates The Brake Assist feature
will automatically disengage when the brake pedal
is released or brake pedal pressure is quickly
decreased.
StabiliTrak®System
The vehicle may have a vehicle stability enhancement
system called StabiliTrak. It is an advanced computer
controlled system that assists the driver with directional
control of the vehicle in difficult driving conditions.
StabiliTrak activates when the computer senses a
discrepancy between the intended path and the direction
the vehicle is actually traveling. StabiliTrak selectively
applies braking pressure at any one of the vehicle’s
brakes to assist the driver with keeping the vehicle
on the intended path.
When the vehicle is started and begins to move, the
system performs several diagnostic checks to insure
there are no problems. The system may be heard or felt
while it is working. This is normal and does not mean
there is a problem with the vehicle. The system should
initialize before the vehicle reaches 20 mph (32 km/h).
In some cases, it may take approximately two miles of
driving before the system initializes.
If cruise control is being used when StabiliTrak
activates, the cruise control automatically disengages.
The cruise control can be re-engaged when road
conditions allow. SeeCruise Control on page 3-13
for more information.
4-6

Before You Go Off-Roading
Have all necessary maintenance and service
work done.
Make sure there is enough fuel, that uid levels are
where they should be, and that the spare tire is fully
inated.
Be sure to read all the information about
four-wheel-drive vehicles in this manual.
Make sure all underbody shields, if the vehicle has
them, are properly attached.
Know the local laws that apply to off-roading where
you will be driving or check with law enforcement
people in the area.
Be sure to get the necessary permission if you will
be on private land.
If you think you will need some more ground clearance
at the front of your vehicle, you can remove the front
fascia lower air dam. The air dam is held in place by
two bolts and 10 snaps accessible from underneath the
front fascia.To remove the air dam:
1. Remove the two outboard air dam bolts.
2. With a at-blade tool, disengage the snaps.
3. After the bolts are removed and the snaps are
disengaged, push forward on the air dam until it
is free.
Notice:Operating your vehicle for extended
periods without the front fascia lower air dam
installed can cause improper air ow to the engine.
Always be sure to replace the front fascia air
dam when you are nished off-road driving.
After off-roading, be sure to reinstall the air dam:
1. Line up the snaps and push the air dam rearward
to engage the snaps.
2. Install the two outboard bolts.
4-13

Driving in Water
{CAUTION:
Driving through rushing water can be dangerous.
Deep water can sweep your vehicle downstream
and you and your passengers could drown. If it
is only shallow water, it can still wash away the
ground from under your tires, and you could lose
traction and roll the vehicle over. Do not drive
through rushing water.
Heavy rain can mean ash ooding, and ood waters
demand extreme caution.
Find out how deep the water is before driving through it.
Do not try it if it is deep enough to cover the wheel hubs,
axles, or exhaust pipe — you probably will not get
through. Deep water can damage the axle and other
vehicle parts.If the water is not too deep, drive slowly through it.
At faster speeds, water splashes on the ignition system
and the vehicle can stall. Stalling can also occur if you get
the tailpipe under water. If the tailpipe is under water, you
will never be able to start the engine. When going through
water, remember that when the brakes get wet, it might
take longer to stop. SeeDriving in Rain and on Wet
Roads on page 4-25.
After Off-Road Driving
Remove any brush or debris that has collected
on the underbody, chassis, or under the hood.
These accumulations can be a re hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the body structure,
steering, suspension, wheels, tires, and exhaust system
for damage and check the fuel lines and cooling system
for any leakage.
The vehicle requires more frequent service due to
off-road use. Refer to the Maintenance Schedule for
additional information.
4-24

Hydroplaning
Hydroplaning is dangerous. Water can build up under
your vehicle’s tires so they actually ride on the water. This
can happen if the road is wet enough and you are going
fast enough. When your vehicle is hydroplaning, it has
little or no contact with the road.
There is no hard and fast rule about hydroplaning.
The best advice is to slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather driving tips
include:
Allow extra following distance.
Pass with caution.
Keep windshield wiping equipment in good shape.
Keep the windshield washer uid reservoir lled.
Have good tires with proper tread depth. SeeTires
on page 5-65.
Turn off cruise control.
Before Leaving on a Long Trip
To prepare your vehicle for a long trip, consider having
it serviced by your dealer/retailer before departing.
Things to check on your own include:
Windshield Washer Fluid:Reservoir full? Windows
clean — inside and outside?
Wiper Blades:In good shape?
Fuel, Engine Oil, Other Fluids:All levels checked?
Lamps:Do they all work and are lenses clean?
Tires:Are treads good? Are tires inated to
recommended pressure?
Weather and Maps:Safe to travel?
Have up-to-date maps?
Highway Hypnosis
Always be alert and pay attention to your surroundings
while driving. If you become tired or sleepy, nd a
safe place to park your vehicle and rest.
Other driving tips include:
Keep the vehicle well ventilated.
Keep interior temperature cool.
Keep your eyes moving — scan the road ahead
and to the sides.
Check the rearview mirror and vehicle instruments
often.
4-26

Hill and Mountain Roads
Driving on steep hills or through mountains is different
than driving on at or rolling terrain. Tips for driving
in these conditions include:
Keep the vehicle serviced and in good shape.
Check all uid levels and brakes, tires, cooling
system, and transmission.
Going down steep or long hills, shift to a lower gear.
{CAUTION:
If you do not shift down, the brakes could get so
hot that they would not work well. You would then
have poor braking or even none going down a hill.
You could crash. Shift down to let the engine
assist the brakes on a steep downhill slope.
{CAUTION:
Coasting downhill in N (Neutral) or with the ignition
off is dangerous. The brakes will have to do all the
work of slowing down and they could get so hot
that they would not work well. You would then
have poor braking or even none going down a hill.
You could crash. Always have the engine running
and the vehicle in gear when going downhill.
Stay in your own lane. Do not swing wide or cut
across the center of the road. Drive at speeds
that let you stay in your own lane.
Top of hills: Be alert — something could be in your
lane (stalled car, accident).
Pay attention to special road signs (falling rocks
area, winding roads, long grades, passing or
no-passing zones) and take appropriate action.
SeeOff-Road Driving on page 4-12for information
about driving off-road.
4-27

{CAUTION:
Snow can trap engine exhaust under the vehicle.
This may cause exhaust gases to get inside.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
If the vehicle is stuck in the snow:
Clear away snow from around the base of
your vehicle, especially any that is blocking
the exhaust pipe.
Check again from time to time to be sure
snow does not collect there.
Open a window about two inches (5 cm) on
the side of the vehicle that is away from the
wind to bring in fresh air.
Fully open the air outlets on or under the
instrument panel.
Adjust the Climate Control system to a setting
that circulates the air inside the vehicle and
set the fan speed to the highest setting.
See Climate Control System in the Index.
CAUTION: (Continued)
CAUTION: (Continued)
For more information about carbon monoxide, see
Engine Exhaust on page 2-55.
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill you.
You cannot see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking the exhaust.
Run the engine for short periods only as needed to
keep warm, but be careful.
To save fuel, run the engine for only short periods as
needed to warm the vehicle and then shut the engine
off and close the window most of the way to save heat.
Repeat this until help arrives but only when you feel really
uncomfortable from the cold. Moving about to keep warm
also helps.
If it takes some time for help to arrive, now and then
when you run the engine, push the accelerator pedal
slightly so the engine runs faster than the idle speed.
This keeps the battery charged to restart the vehicle and
to signal for help with the headlamps. Do this as little as
possible to save fuel.
4-29

Driving with a Trailer
{CAUTION:
When towing a trailer, exhaust gases may collect
at the rear of the vehicle and enter if the liftgate,
trunk/hatch, or rear-most window is open.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
To maximize safety when towing a trailer:
Have the exhaust system inspected for
leaks and make necessary repairs before
starting a trip.
Never drive with the liftgate, trunk/hatch,
or rear-most window open.
Fully open the air outlets on or under the
instrument panel.
Adjust the Climate Control system to a setting
that brings in only outside air and set the fan
speed to the highest setting. See Climate
Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 2-55.Towing a trailer requires a certain amount of
experience. Get to know the rig before setting out for the
open road. Get acquainted with the feel of handling and
braking with the added weight of the trailer. And always
keep in mind that the vehicle you are driving is now
longer and not as responsive as the vehicle is by itself.
Before starting, check all trailer hitch parts and
attachments, safety chains, electrical connectors, lamps,
tires and mirror adjustments. If the trailer has electric
brakes, start the vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure the
brakes are working. This checks the electrical connection
at the same time.
During the trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
While towing a trailer or when exposed to long periods
of sunshine, the oor of the truck bed may become
very warm. Avoid putting items in the truck bed
that might be affected by high ambient temperatures.
4-77

Maintenance When Trailer Towing
The vehicle needs service more often when pulling a
trailer. See this manual’s Maintenance Schedule or Index
for more information. Things that are especially important
in trailer operation are automatic transmission uid,
engine oil, axle lubricant, belts, cooling system and brake
system. It is a good idea to inspect these before and
during the trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
The vehicle is equipped with one of the following
wiring harnesses for towing a trailer or hauling a
slide-in camper.
Basic Trailer Wiring
All regular, extended cab and crew cab pickups have a
seven-wire trailer towing harness.
For vehicles not equipped with heavy duty trailering,
the harness is secured to the vehicle’s frame behind the
spare tire mount. The harness requires the installation
of a trailer connector, which is available through
your dealer/retailer.
If towing a light-duty trailer with a standard four-way
round pin connector, an adapter is available from your
dealer/retailer.
4-81

Service............................................................5-4
Accessories and Modications..........................5-4
California Proposition 65 Warning.....................5-5
California Perchlorate Materials
Requirements.............................................5-5
Doing Your Own Service Work.........................5-5
Adding Equipment to the Outside of
the Vehicle.................................................5-6
Fuel................................................................5-6
Gasoline Octane............................................5-6
Gasoline Specications....................................5-7
California Fuel...............................................5-7
Additives.......................................................5-7
Fuel E85 (85% Ethanol)..................................5-8
Fuels in Foreign Countries...............................5-9
Filling the Tank............................................5-10
Filling a Portable Fuel Container.....................5-12
Checking Things Under the Hood....................5-12
Hood Release..............................................5-13
Engine Compartment Overview.......................5-14
Engine Oil...................................................5-15
Engine Oil Life System..................................5-18
Engine Air Cleaner/Filter................................5-19Automatic Transmission Fluid (4-Speed
Transmission)...........................................5-21
Automatic Transmission Fluid (6-Speed
Transmission)...........................................5-24
Cooling System............................................5-28
Engine Coolant.............................................5-29
Engine Overheating.......................................5-34
Overheated Engine Protection
Operating Mode........................................5-37
Engine Fan Noise.........................................5-37
Power Steering Fluid.....................................5-38
Windshield Washer Fluid................................5-39
Brakes........................................................5-40
Battery........................................................5-43
Jump Starting...............................................5-44
Rear Axle.......................................................5-49
Four-Wheel Drive............................................5-51
Front Axle......................................................5-53
Noise Control System.....................................5-54
Tampering with Noise Control System
Prohibited.................................................5-54
Headlamp Aiming...........................................5-55
Section 5 Service and Appearance Care
5-1

This vehicle has an airbag system. Before attempting to
do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-88.
Keep a record with all parts receipts and list the mileage
and the date of any service work performed. See
Maintenance Record on page 6-19.
Adding Equipment to the Outside of
the Vehicle
Things added to the outside of the vehicle can affect
the airow around it. This can cause wind noise and can
affect fuel economy and windshield washer performance.
Check with your dealer/retailer before adding equipment
to the outside of the vehicle.
Fuel
For diesel engine vehicles, see “Diesel Fuel
Requirements and Fuel System” in the DURAMAX®
Diesel manual.
For vehicles with gasoline engines, please read this.
Gasoline
Use of the recommended fuel is an important part of the
proper maintenance of this vehicle. To help keep the
engine clean and maintain optimum vehicle performance,
we recommend the use of gasoline advertised as TOP
TIER Detergent Gasoline.The 8th digit of the Vehicle Identication Number (VIN)
shows the code letter or number that identies the
vehicle’s engine. The VIN is at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-121.
If the vehicle has the 5.3L V8 engine (VIN Code 0), the
5.3L V8 engine (VIN Code 3), or the 6.2L V8 engine
(VIN Code 2), you can use either unleaded gasoline
or ethanol fuel containing up to 85% ethanol (E85).
SeeFuel E85 (85% Ethanol) on page 5-8. In all other
gasoline engines, use only unleaded gasoline.
SeeGasoline Octane on page 5-6.
Gasoline Octane
For all vehicles except those with the 6.2L V8 engine
(VIN Code 2), use regular unleaded gasoline with
a posted octane rating of 87 or higher. If the octane
rating is less than 87, you might notice an audible
knocking noise when you drive, commonly referred to
as spark knock. If this occurs, use a gasoline rated at
87 octane or higher as soon as possible. If you are using
gasoline rated at 87 octane or higher and you hear
heavy knocking, the engine needs service.
If the vehicle has the 6.2L V8 engine (VIN Code 2), 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 you might
5-6