2007 GMC SIERRA CLASSIC overheating

How to Check and Add Fluid
The proper uid should be added if the level does
not reach the bottom of the diaphragm when it
is in place in the reservoir. See the instructions on
the reservoir cap.
Engine Coolant
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 505.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.
502

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 508.
{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.
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 480for more
information on location.
Engine Overheating
You will nd a coolant temperature gage on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 256.
In addition, you will nd an ENGINE
OVERHEATED and a REDUCED ENGINE
POWER message in the Driver Information
Center (DIC) on the instrument panel. SeeDIC
Warnings and Messages on page 270.
505

A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan
{CAUTION:
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.
If the coolant inside the coolant surge tank is
boiling, do not do anything else until it cools down.
The vehicle should be parked on a level surface.
Check the coolant level after the system cools
down. Some amount of coolant may be lost due to
overheating.
All Other Engines
509

Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and where
to obtain service, see your GM Warranty booklet
for details. For additional information refer to
the tire manufacturer’s booklet included with your
vehicle.
{CAUTION:
Poorly maintained and improperly used
tires are dangerous.
Overloading your vehicle’s tires can
cause overheating as a result of too
much friction. You could have an
air-out and a serious accident. See
Loading Your Vehicle on page 409.
CAUTION: (Continued)
CAUTION: (Continued)

Underinated tires pose the
samedanger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
Tire pressure should be checked when
your vehicle’s tires are cold. See
Inflation - Tire Pressure on page 551.
Overinated tires are more likely
to be cut, punctured, or broken by a
sudden impact — such as when
you hit a pothole. Keep tires at the
recommended pressure.
Worn, old tires can cause accidents.
If the tire’s tread is badly worn, or
if your vehicle’s tires have been
damaged, replace them.
543

Engine (cont.)
Check and Service Engine Soon Light..... 258
Coolant.................................................... 502
Coolant Heater......................................... 139
Coolant Temperature Gage...................... 256
Drive Belt Routing.................................... 633
Engine Compartment Overview................ 480
Exhaust................................................... 174
Fan Noise................................................ 514
Oil ........................................................... 486
Oil Life System........................................ 489
Overheated Protection Operating Mode.... 508
Overheating............................................. 505
Starting.................................................... 137
Entry Lighting.............................................. 227
Event Data Recorders (EDR)...................... 650
Exit Lighting................................................ 227
Extender, Safety Belt..................................... 43
F
Filter
Engine Air Cleaner................................... 491
Finish Damage............................................ 596
Fixed Mast Antenna.................................... 353
Flashers, Hazard Warning........................... 212Flash-to-Pass.............................................. 216
Flat Tire...................................................... 563
Flat Tire, Changing...................................... 564
Flat Tire, Storing......................................... 584
Fluid
Automatic Transmission...................494, 497
Manual Transmission................................ 500
Power Steering........................................ 515
Windshield Washer.................................. 516
Fog Lamps.................................................. 225
Four-Wheel Drive...............................153, 528
Four-Wheel-Drive Light................................ 263
Front Axle................................................... 529
Front Reading Lamps.................................. 227
Front Storage Area...................................... 202
Fuel............................................................ 470
Additives.................................................. 472
California Fuel.......................................... 471
E85 (85% Ethanol)................................... 473
Filling a Portable Fuel Container.............. 477
Filling Your Tank...................................... 474
Fuels in Foreign Countries....................... 474
Gage....................................................... 264
Gasoline Octane...................................... 470
Gasoline Specications............................ 471
Low Warning Light................................... 265
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