warning GMC SIERRA 2007 Workshop Manual

Notice:Use only engine oil identied as
meeting GM Standard GM6094M and showing
the American Petroleum Institute Certied
For Gasoline Engines starburst symbol. Failure
to use the recommended oil can result in
engine damage not covered by your warranty.
GM Goodwrench
®oil meets all the requirements
for your vehicle.
If you are in an area of extreme cold, where the
temperature falls below−20°F (−29°C), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both provide
easier cold starting and better protection for
the engine at extremely low temperatures.
Engine Oil Additives
Do not add anything to the oil. The recommended
oils with the starburst symbol that meet GM
Standard GM6094M are all you need for good
performance and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you
know when to change the engine oil and lter.
This is based on engine revolutions and engine
temperature, and not on mileage. Based on driving
conditions, the mileage at which an oil change
will be indicated can vary considerably. For the oil
life system to work properly, you must reset the
system every time the oil is changed.
When the system has calculated that oil life has
been diminished, it will indicate that an oil change
is necessary. A CHANGE ENGINE OIL SOON
message will come on. SeeDIC Warnings
and Messages on page 279. Change your oil
as soon as possible within the next 600 miles
(1 000 km). It is possible that, if you are driving
under the best conditions, the oil life system may
not indicate that an oil change is necessary for
over a year. However, your engine oil and
lter must be changed at least once a year and
at this time the system must be reset.
503

What to Do with Used Oil
Used engine oil contains certain elements that may
be unhealthy for your skin and could even cause
cancer. Do not let used oil stay on your skin for very
long. Clean your skin and nails with soap and
water, or a good hand cleaner. Wash or properly
dispose of clothing or rags containing used engine
oil. See the manufacturer’s warnings about the use
and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from
the lter before disposal. Never dispose of oil by
putting it in the trash, pouring it on the ground, into
sewers, or into streams or bodies of water. Instead,
recycle it by taking it to a place that collects used
oil. If you have a problem properly disposing of
used oil, ask your dealer, a service station, or a
local recycling center for help.
Engine Air Cleaner/Filter (Gasoline
Engines)
If your vehicle has a diesel engine, see “Pickup
Models” under “Engine Air Cleaner/Filter” in
the DURAMAX
®Diesel Supplement for the correct
inspection and replacement procedures.
SeeEngine
Compartment Overview
on page 498for the
location of the engine
air cleaner/lter and
the air lter restriction
indicator, if the
vehicle has one.
505

Engine Coolant
If your vehicle has the DURAMAX®Diesel engine,
see the DURAMAX®Diesel manual for more
information.
The cooling system in your vehicle is lled with
DEX-COOL
®engine coolant. This coolant is
designed to remain in your vehicle for ve years or
150,000 miles (240 000 km), whichever occurs
rst, if you add only DEX-COOL
®extended
life coolant.
The following explains your cooling system and
how to add coolant when it is low. If you have
a problem with engine overheating, seeEngine
Overheating on page 516.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down
to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant may require changing sooner, at
the rst maintenance service after each
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would not
be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
513

What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not be
covered by your warranty. Too much water
in the mixture can freeze and crack the engine,
radiator, heater core, and other parts.
If you have to add coolant more than four times a
year, have your dealer check your cooling
system.
Notice:If you use extra inhibitors and/or
additives in your vehicle’s cooling system, you
could damage your vehicle. Use only the
proper mixture of the engine coolant listed in
this manual for the cooling system. See
Recommended Fluids and Lubricants on
page 635for more information.
514

Checking Coolant
The coolant surge tank is located in the engine
compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview on
page 498for more information on location.
{CAUTION:
Turning the surge tank pressure cap when
the engine and radiator are hot can allow
steam and scalding liquids to blow out
and burn you badly. Never turn the surge
tank pressure cap — even a little — when
the engine and radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the
FULL COLD mark on the coolant surge tank.
If your vehicle has a low coolant sensor and the
LOW COOLANT LEVEL message comes on
and stays on, it means you are low on engine
coolant. See “LOW COOLANT LEVEL” underDIC
Warnings and Messages on page 279.
Adding Coolant
If you need more coolant, add the proper
DEX-COOL®coolant mixture at the surge tank,
but only when the engine is cool. SeeCooling
System on page 520for more information.
{CAUTION:
You can be burned if you spill coolant on
hot engine parts. Coolant contains
ethylene glycol, and it will burn if the
engine parts are hot enough. Do not spill
coolant on a hot engine.
When replacing the pressure cap, make sure it is
hand-tight and fully seated.
515

Coolant Surge Tank Pressure Cap
Notice:If the pressure cap is not tightly
installed, coolant loss and possible engine
damage may occur. Be sure the cap is properly
and tightly secured.
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank. SeeEngine
Compartment Overview on page 498for more
information on location.
Engine Overheating
If your vehicle has the DURAMAX®Diesel engine,
see the DURAMAX®Diesel manual for more
information.
You will nd a coolant temperature gage on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 258.
In addition, you will nd ENGINE OVERHEATED
STOP ENGINE, ENGINE OVERHEATED IDLE
ENGINE, and ENGINE POWER IS REDUCED
messages in the Driver Information Center (DIC)
on the instrument panel. SeeDIC Warnings
and Messages on page 279.
516

If No Steam Is Coming From Your
Engine
The ENGINE OVERHEATED STOP ENGINE or
the ENGINE OVERHEATED IDLE ENGINE
message, along with a low coolant condition, can
indicate a serious problem.
If you get an engine overheat warning, but see or
hear no steam, the problem may not be too
serious. Sometimes the engine can get a little too
hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. SeeTowing a Trailer on
page 445.If you get the ENGINE OVERHEATED STOP
ENGINE or the ENGINE OVERHEATED IDLE
ENGINE message with no sign of steam, try this
for a minute or so:
1. If you have an air conditioner and it is on,
turn it off.
2. Turn on your heater to full hot at the
highest fan speed and open the windows
as necessary.
3. If you are stopped in a traffic jam, apply
the brake, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving — DRIVE (D) or THIRD (3).
If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not come
back on, you can drive normally.
518

If the warning continues, pull over, stop, and park
your vehicle immediately.
If there is still no sign of steam and your vehicle
has an engine-driven cooling fan, push down
the accelerator until the engine speed is about
twice as fast as normal idle speed for at least
ve minutes while you are parked.
If there is still no sign of steam and your vehicle
has an electric cooling fan, idle the engine for
ve minutes while you are parked.
If you still have the warning, turn off the engine
and get everyone out of the vehicle until it
cools down. Also, see “Overheated Engine
Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get
service help right away.Overheated Engine Protection
Operating Mode (V8 Engines Only)
If an overheated engine condition exists and
the REDUCED ENGINE POWER message
is displayed, an overheat protection mode which
alternates ring groups of cylinders helps
prevent engine damage. In this mode, you will
notice a loss in power and engine performance.
This operating mode allows your vehicle to
be driven to a safe place in an emergency. Driving
extended miles (km) 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. SeeEngine Oil (Gasoline Engine) on
page 500.
519

{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and a proper coolant.
Notice:In cold weather, water can freeze and
crack the engine, radiator, heater core and
other parts. Use the recommended coolant and
the proper coolant mixture.
{CAUTION:
You can be burned if you spill coolant on
hot engine parts. Coolant contains
ethylene glycol and it will burn if the
engine parts are hot enough. Do not spill
coolant on a hot engine.
1. Remove the coolant
surge tank pressure
cap when the
cooling system,
including the coolant
surge tank
pressure cap and
upper radiator hose,
is no longer hot.
Turn the pressure cap slowly counterclockwise
about one full turn. If you hear a hiss, wait
for that to stop. A hiss means there is
still some pressure left.
523

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 616.
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.
530