2007 CHEVROLET SILVERADO service indicator

If, after several seconds, both status indicator
lights remain on, or if there are no lights at
all, there may be a problem with the lights or the
passenger sensing system. See your
dealer/retailer for service.
{CAUTION:
If the airbag readiness light in the
instrument panel cluster ever comes on
and stays on, it means that something may
be wrong with the airbag system. If this
ever happens, have the vehicle serviced
promptly, because an adult-size person
sitting in the right front passenger’s seat
may not have the protection of the
airbag(s). SeeAirbag Readiness Light on
page 252for more on this, including
important safety information.
Charging System Light
If this light comes on
when the engine is
running, there could be
a problem with the
charging system.
This light will also stay on while the key is in RUN
until the engine is started.
If the light stays on after starting the engine it
could indicate a problem with the generator drive
belt, or some other charging system problem.
Have it checked right away. Driving while this light
is on could drain the battery.
If you must drive a short distance with this light
on, it helps to turn off all of the electrical
accessories, such as the radio and the blower.
256

StabiliTrak®Indicator Light
If equipped, this warning
light should come on
briey when the engine
is started.
If the warning light does not come on then, have it
xed so it will be ready to warn you if there is a
problem. If it stays on, or comes on when you are
driving, there may be a problem with your
StabiliTrak
®system and your vehicle may need
service. When this warning light is on, the system
is off and will not limit wheel spin. Adjust your
driving accordingly.
This light will also ash when the StabiliTrak
®
system is active.
If the StabiliTrak
®system warning light comes on
and stays on for an extended period of time
when the system is turned on, your vehicle needs
service. SeeStabiliTrak
®System on page 384
for more information.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard your
vehicle is working. During a majority of the
operation, the gage will read 210°F (100°C) or
less. If you are pulling a load or going up hills, it is
normal for the temperature to uctuate and go
over the 235°F (113°C) mark. However, if the gage
reaches the 260°F (125°C) mark, it indicates
that the cooling system is working beyond
its capacity.
SeeEngine Overheating on page 517.
United StatesCanada
260

Malfunction Indicator Lamp
Check Engine Light
Your vehicle has a
computer which
monitors operation of
the fuel, ignition,
and emission control
systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended
to assure that emissions are at acceptable
levels for the life of the vehicle, helping to produce
a cleaner environment. The check engine light
comes on to indicate that there is a problem and
service is required. Malfunctions often will be
indicated by the system before any problem is
apparent. This may prevent more serious damage
to your vehicle. This system is also designed to
assist your service technician in correctly
diagnosing any malfunction.Notice:If you keep driving your vehicle with
this light on, after awhile, the emission controls
might not work as well, your vehicle’s fuel
economy might not be as good, and the engine
might not run as smoothly. This could lead
to costly repairs that might not be covered by
your warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system
of your vehicle or the replacement of the
original tires with other than those of the same
Tire Performance Criteria (TPC) can affect
your vehicle’s emission controls and can cause
this light to come on. Modications to these
systems could lead to costly repairs not
covered by your warranty. This could also
result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 488.
262

Gasoline Octane
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.
Gasoline Specications
At a minimum, gasoline should meet ASTM
specication D 4814 in the United States or
CAN/CGSB-3.5 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT). General Motors recommends against the
use of gasolines containing MMT. SeeAdditives
on page 492for additional information.
California Fuel
If your vehicle is certied to meet California
Emissions Standards, it is designed to operate on
fuels that meet California specications. See
the underhood emission control label. If this fuel is
not available in states adopting California
emissions standards, your vehicle will operate
satisfactorily on fuels meeting federal
specications, but emission control system
performance may be affected. The malfunction
indicator lamp may turn on and your vehicle may
fail a smog-check test. SeeMalfunction Indicator
Lamp on page 262. If this occurs, return to
your authorized GM dealer for diagnosis. If it is
determined that the condition is caused by the type
of fuel used, repairs may not be covered by
your warranty.
491

Additives
To provide cleaner air, all gasolines in the United
States are now required to contain additives
that will help prevent engine and fuel system
deposits from forming, allowing your emission
control system to work properly. In most cases,
you should not have to add anything to your fuel.
However, some gasolines contain only the
minimum amount of additive required to meet U.S.
Environmental Protection Agency regulations.
To help keep fuel injectors and intake valves clean,
or if your vehicle experiences problems due to
dirty injectors or valves, look for gasoline that is
advertised as TOP TIER Detergent Gasoline. Also,
your dealer has additives that will help correct
and prevent most deposit-related problems.
Gasolines containing oxygenates, such as
ethers and ethanol, and reformulated gasolines
may be available in your area. General Motors
recommends that you use these gasolines if they
comply with the specications described earlier.
However, E85 (85% ethanol) and other fuels
containing more than 10% ethanol must not be
used in vehicles that were not designed for
those fuels.Notice:Your vehicle was not designed for
fuel that contains methanol. Do not use
fuel containing methanol. It can corrode metal
parts in the fuel system and also damage
plastic and rubber parts. That damage would
not be covered under your warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing
additive called methylcyclopentadienyl manganese
tricarbonyl (MMT); ask the attendant where you
buy gasoline whether the fuel contains MMT.
General Motors recommends against the use of
such gasolines. Fuels containing MMT can reduce
the life of spark plugs and the performance of
the emission control system may be affected. The
malfunction indicator lamp may turn on. If this
occurs, return to your dealer for service.
492

Fuel E85 (85% Ethanol)
The 8th digit of the Vehicle Identication Number
(VIN) shows the code letter or number that
identies your vehicle’s engine. The VIN is at the
top left of the instrument panel. SeeVehicle
Identication Number (VIN) on page 610.
If your vehicle has the 5.3L V8 engine (VIN Code
0) or the 5.3L V8 engine (VIN Code 3), you
can use either regular unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E85);
also seeFuel on page 490. In all other engines,
use only the unleaded gasoline described
underGasoline Octane on page 491.
Only vehicles that have the 5.3L V8 engine (VIN
Code 0) or the 5.3L V8 engine (VIN Code 3)
can use 85% ethanol fuel (E85). We encourage
the use of E85 in vehicles that are designed to use
it. The ethanol in E85 is a “renewable” fuel,
meaning it is made from renewable sources such
as corn and other crops.
Many service stations will not have an 85%
ethanol fuel (E85) pump available. The U. S.
Department of Energy has an alternative fuels
website (www.eere.energy.gov/afdc/infrastructure/
locator.html) that can help you nd E85 fuel.Those stations that do have E85 should have a
label indicating ethanol content. Do not use the fuel
if the ethanol content is greater than 85%.
At a minimum, E85 should meet ASTM
Specication D 5798. By denition, this means that
fuel labeled E85 will have an ethanol content
between 70% and 85%. Filling the fuel tank with
fuel mixtures that do not meet ASTM specications
can affect driveability and could cause the
malfunction indicator lamp to come on.
To ensure quick starts in the wintertime, the E85
fuel must be formulated properly for your climate
according to ASTM specication D 5798. If you
have trouble starting on E85, it could be because
the E85 fuel is not properly formulated for your
climate. If this happens, switching to gasoline or
adding gasoline to the fuel tank can improve
starting. For good starting and heater efficiency
below 32°F (0°C), the fuel mix in the fuel tank
should contain no more than 70% ethanol. It is best
not to alternate repeatedly between gasoline and
E85. If you do switch fuels, it is recommended that
you add as much fuel as possible — do not add
less than three gallons (11 L) when refueling. You
should drive the vehicle immediately after refueling
for at least seven miles (11 km) to allow the vehicle
to adapt to the change in ethanol concentration.
493

Notice:
Using the wrong uid can badly damage
brake system parts. For example, just a
few drops of mineral-based oil, such
as engine oil, in the brake system can
damage brake system parts so badly that
they will have to be replaced. Do not
let someone put in the wrong kind of uid.
If you spill brake uid on your vehicle’s
painted surfaces, the paint nish can
be damaged. Be careful not to spill brake
uid on your vehicle. If you do, wash it
off immediately. SeeWashing Your Vehicle
on page 605.
Brake Wear
Your vehicle has front disc brakes and could have
rear drum brakes or rear disc brakes.
Disc brake pads have built-in wear indicators that
make a high-pitched warning sound when the
brake pads are worn and new pads are needed.
The sound can come and go or be heard all
the time your vehicle is moving, except when you
are pushing on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That
could lead to an accident. When you hear
the brake wear warning sound, have your
vehicle serviced.
Notice:Continuing to drive with worn-out
brake pads could result in costly brake repair.
Some driving conditions or climates can cause
a brake squeal when the brakes are rst applied or
lightly applied. This does not mean something is
wrong with the brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated,
inspect brake pads for wear and evenly tighten
wheel nuts in the proper sequence to torque
specications inCapacities and Specications on
page 620.
531

If you have rear drum brakes, they do not have
wear indicators, but if you ever hear a rear brake
rubbing noise, have the rear brake linings
inspected immediately. Rear brake drums should
be removed and inspected each time the tires
are removed for rotation or changing. Drum brakes
have an inspection hole to inspect lining wear
during scheduled maintenance. When you have
the front brake pads replaced, have the rear
brakes inspected, too.
Brake linings should always be replaced as
complete axle sets.
Brake Pedal Travel
See your dealer/retailer if the brake pedal does
not return to normal height, or if there is a
rapid increase in pedal travel. This could be a sign
that brake service might be required.
Brake Adjustment
Every time you make a brake stop, the brakes
adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its
many parts have to be of top quality and work well
together if the vehicle is to have really good
braking. Your vehicle was designed and tested
with top-quality brake parts. When you replace
parts of the braking system — for example, when
the brake linings wear down and you need
new ones put in — be sure you get new approved
replacement parts. If you do not, the brakes
might not work properly. For example, if someone
puts in brake linings that are wrong for your
vehicle, the balance between the front and rear
brakes can change — for the worse. The braking
performance you have come to expect can
change in many other ways if someone puts in the
wrong replacement brake parts.
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