2007 CHEVROLET SILVERADO coolant

ENGINE OVERHEATED IDLE ENGINE
Notice:If you drive your vehicle while the
engine is overheating, severe engine damage
may occur. If an overheat warning appears
on the instrument panel cluster and/or
DIC, stop the vehicle as soon as possible. See
Engine Overheating on page 517for more
information.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle
to idle until it cools down. SeeEngine Coolant
Temperature Gage on page 260.
SeeOverheated Engine Protection Operating
Mode (V8 Engines Only) on page 520for
information on driving to a safe place in an
emergency.
ENGINE OVERHEATED STOP ENGINE
Notice:If you drive your vehicle while the
engine is overheating, severe engine damage
may occur. If an overheat warning appears
on the instrument panel cluster and/or
DIC, stop the vehicle as soon as possible. See
Engine Overheating on page 517for more
information.This message displays and a chime sounds if the
engine cooling system reaches unsafe
temperatures for operation. Stop and turn off the
vehicle as soon as it is safe to do so to avoid
severe damage. This message clears when the
engine has cooled to a safe operating temperature.
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. SeeEngine Overheating on
page 517for 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 for service as soon as possible.
284

Turn Signals When Towing a Trailer
The arrows on your instrument panel will
ash whenever you signal a turn or lane change.
Properly hooked up, the trailer lamps will also
ash, telling other drivers you’re about to
turn, change lanes or stop.
When towing a trailer, the arrows on your
instrument panel will ash for turns even if the
bulbs on the trailer are burned out. Thus, you may
think drivers behind you are seeing your signal
when they are not. It’s important to check
occasionally to be sure the trailer bulbs are still
working.
Driving On Grades
Reduce speed and shift to a lower gearbefore
you start down a long or steep downgrade. If you
don’t shift down, you might have to use your
brakes so much that they would get hot and no
longer work well.
You can tow in DRIVE (D). You may want to shift
the transmission to lower gear selection if the
transmission shifts too often (e.g., under heavy
loads and/or hilly conditions).You may also want to activate the tow/haul mode
if the transmission shifts too often. SeeTow/Haul
Mode Light on page 268.
When towing at high elevation on steep uphill
grades, consider the following: Engine coolant at
higher elevations will boil at a lower temperature
than at or near sea level. If you turn your
engine off immediately after towing at high
elevation on steep uphill grades, your vehicle may
show signs similar to engine overheating. To
avoid this, let the engine run while parked,
preferably on level ground, with the transmission
in PARK (P) at least ve minutes before turning the
engine off. If you do get the overheat warning,
seeEngine Overheating on page 517.
477

Service........................................................ 488
Accessories and Modications................... 488
California Proposition 65 Warning.............. 489
Doing Your Own Service Work.................. 489
Adding Equipment to the Outside of
Your Vehicle.......................................... 490
Fuel............................................................. 490
Gasoline Octane........................................ 491
Gasoline Specications.............................. 491
California Fuel........................................... 491
Additives................................................... 492
Fuel E85 (85% Ethanol)............................ 493
Fuels in Foreign Countries........................ 494
Filling the Tank......................................... 494
Filling a Portable Fuel Container............... 497
Checking Things Under the Hood.............. 498
Hood Release........................................... 498
Engine Compartment Overview.................. 500
Engine Oil (Gasoline Engine).................... 502
Engine Oil Life System.............................. 505Engine Air Cleaner/Filter
(Gasoline Engines)................................. 507
Automatic Transmission Fluid.................... 510
Engine Coolant.......................................... 514
Coolant Surge Tank Pressure Cap............ 517
Engine Overheating................................... 517
Overheated Engine Protection
Operating Mode (V8 Engines Only)........ 520
Cooling System......................................... 521
Engine Fan Noise..................................... 526
Power Steering Fluid................................. 526
Windshield Washer Fluid........................... 527
Brakes...................................................... 529
Battery...................................................... 533
Jump Starting............................................ 534
Rear Axle.................................................... 540
Four-Wheel Drive........................................ 541
Front Axle................................................... 543
Section 5 Service and Appearance Care
485

Checking Things Under
the Hood
{CAUTION:
An electric engine cooling fan can start
even when the engine is not running.
To avoid injury, always keep hands,
clothing, and tools away from any engine
cooling fan.
{CAUTION:
Things that burn can get on hot engine
parts and start a re. These include
liquids like fuel, oil, coolant, brake uid,
windshield washer and other uids, 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 do the following:
1. Pull the handle with
this symbol on it. It
is located inside
the vehicle to the left
of the brake
pedal.
498

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter (Gasoline Engines) on page 507.
B. Air Filter Restriction Indicator (If Equipped).
SeeEngine Air Cleaner/Filter (Gasoline
Engines) on page 507.
C. Coolant Surge Tank and Pressure Cap. See
Cooling System on page 521andCoolant
Surge Tank Pressure Cap on page 517.
D. Positive (+) Terminal. SeeJump Starting on
page 534.
E. Battery. SeeBattery on page 533.
F. Engine Oil Fill Cap. See “When to Add Engine
Oil” underEngine Oil (Gasoline Engine) on
page 502.
G. Automatic Transmission Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 510.H. Remote Negative (−) Terminal (Out of View).
SeeJump Starting on page 534.
I. Engine Oil Dipstick (Out of View). See
“Checking Engine Oil” underEngine Oil
(Gasoline Engine) on page 502.
J. Engine Cooling Fan. SeeCooling System on
page 521.
K. Power Steering Fluid Reservoir. SeePower
Steering Fluid on page 526.
L. Brake Master Cylinder Reservoir. See “Brake
Fluid” underBrakes on page 529.
M. Underhood Fuse Block. SeeUnderhood Fuse
Block on page 615.
N. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield
Washer Fluid on page 527.
501

Consistency of Readings
Always check the uid level at least twice using
the procedures described. Consistency (repeatable
readings) is important to maintaining proper uid
level. If uid is added, it may take 15 minutes
or longer to obtain an accurate reading because of
residual uid draining down the dipstick tube. If
inconsistent readings persist, check the
transmission breather to be sure it is clean and
not clogged. If readings are still inconsistent,
contact your dealer.
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 517.
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.
514

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 639for more information.
515

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 500for 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 281.
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 521for 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.
516