2007 CHEVROLET TAHOE cooling

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. SeeEngine
Overheating on page 473for 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 473for 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.
FUEL LEVEL LOW
This message displays and a chime sounds if the
fuel level is low. Refuel as soon as possible.
SeeFuel Gage on page 259andFuel on page 446
for more information.
HOOD OPEN
This message displays and a chime sounds if the
hood is not fully closed. Stop and turn off the
vehicle, check the hood for obstructions, and close
the hood again. Check to see if the message
still appears on the DIC.
273

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 you drive
through it. If it is deep enough to cover your wheel
hubs, axles, or exhaust pipe, do not try it — you
probably will not get through. Also, water that deep
can damage your axle and other vehicle parts.If the water is not too deep, drive slowly through it.
At faster speeds, water splashes on your ignition
system and your vehicle can stall. Stalling can also
occur if you get your tailpipe under water. And,
as long as your tailpipe is under water, you
will never be able to start your engine. When you
go through water, remember that when your
brakes get wet, it may take you longer to stop.
SeeDriving in Rain and on Wet Roads on page 390
for more information on driving through water.
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. Also, check
the fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service
due to off-road use. Refer to the Maintenance
Schedule for additional information.
388

Hill and Mountain Roads
Driving on steep hills or mountains is different
from driving in at or rolling terrain.If you drive regularly in steep country, or if you are
planning to visit there, here are some tips that
can make your trips safer and more enjoyable. See
Off-Road Driving on page 372for information
about driving off-road.
Keep your vehicle in good shape. Check all
uid levels and also the brakes, tires,
cooling system, and transmission. These parts
can work hard on mountain roads.
{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.
398

Driving with a Trailer
{CAUTION:
If you have a rear-most window open and
you pull a trailer with your vehicle, carbon
monoxide (CO) could come into your
vehicle. You cannot see or smell CO. It
can cause unconsciousness or death. See
Engine Exhaust on page 160. To maximize
your safety when towing a trailer:
Have your exhaust system inspected
for leaks, and make necessary repairs
before starting on your trip.
CAUTION: (Continued)
CAUTION: (Continued)

Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or
another opening, drive with your front,
main heating or cooling system on
and with the fan on any speed. This
will bring fresh, outside air into your
vehicle. Do not use the climate control
setting for maximum air because it
only recirculates the air inside your
vehicle. SeeClimate Control System
on page 227.
Towing a trailer requires a certain amount of
experience. Before setting out for the open road,
you’ll want to get to know your rig. Acquaint
yourself 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 a good deal longer and not nearly as
responsive as your vehicle is by itself.
433

CAUTION: (Continued)
If the transfer case on four-wheel-drive
vehicles is in NEUTRAL, your vehicle will
be free to roll, even if your shift lever is in
PARK (P). So, be sure the transfer case is
in a drive gear — not in NEUTRAL.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal
down while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the
chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when
you’re pulling a trailer. See the Maintenance
Schedule for more on this. Things that are
especially important in trailer operation are
automatic transmission uid (don’t overll), engine
oil, axle lubricant, belts, cooling system and
brake system. Each of these is covered in this
manual, and the Index will help you nd them
quickly. If you’re trailering, it’s a good idea
to review these sections before you start your trip.
Check periodically to see that all hitch nuts and
bolts are tight.
437

Service........................................................ 444
Accessories and Modications................... 444
California Proposition 65 Warning.............. 445
Doing Your Own Service Work.................. 445
Adding Equipment to the Outside of
Your Vehicle.......................................... 446
Fuel............................................................. 446
Gasoline Octane........................................ 447
Gasoline Specications.............................. 447
California Fuel........................................... 447
Additives................................................... 448
Fuel E85 (85% Ethanol)............................ 449
Fuels in Foreign Countries........................ 450
Filling the Tank......................................... 451
Filling a Portable Fuel Container............... 455
Checking Things Under the Hood.............. 456
Hood Release........................................... 457
Engine Compartment Overview.................. 458
Engine Oil................................................. 459
Engine Oil Life System.............................. 462
Engine Air Cleaner/Filter............................ 464
Automatic Transmission Fluid.................... 466
Engine Coolant.......................................... 470Coolant Surge Tank Pressure Cap............ 473
Engine Overheating................................... 473
Overheated Engine Protection
Operating Mode..................................... 476
Cooling System......................................... 477
Engine Fan Noise..................................... 483
Power Steering Fluid ................................. 484
Windshield Washer Fluid........................... 485
Brakes...................................................... 486
Battery...................................................... 490
Jump Starting............................................ 491
Rear Axle.................................................... 496
Four-Wheel Drive........................................ 497
Front Axle................................................... 498
Headlamp Aiming........................................ 499
Bulb Replacement....................................... 502
Halogen Bulbs........................................... 502
Taillamps, Turn Signal, Stoplamps and
Back-up Lamps...................................... 502
License Plate Lamp................................... 504
Replacement Bulbs................................... 504
Section 5 Service and Appearance Care
441

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 464.
B. Air Filter Restriction Indicator (If Equipped).
SeeEngine Air Cleaner/Filter on page 464.
C. Coolant Surge Tank and Pressure Cap.
SeeCooling System on page 477andCoolant
Surge Tank Pressure Cap on page 473.
D. Remote Positive (+) Terminal. SeeJump
Starting on page 491.
E. Battery. SeeBattery on page 490.
F. Engine Oil Fill Cap. See “When to Add Engine
Oil” underEngine Oil on page 459.
G. Automatic Transmission Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 466.
H. Remote Negative (−) Terminal (Out of View).
SeeJump Starting on page 491.
I. Engine Oil Dipstick (Out of View). See
“Checking Engine Oil” underEngine Oil on
page 459.
J. Engine Cooling Fan. SeeCooling System on
page 477.
K. Power Steering Fluid Reservoir. SeePower
Steering Fluid on page 484.L. Brake Master Cylinder Reservoir. See “Brake
Fluid” underBrakes on page 486.
M. Underhood Fuse Block. SeeUnderhood Fuse
Block on page 567.
N. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield
Washer Fluid on page 485.
Engine Oil
If the CHECK OIL LEVEL message in the Driver
Information Center (DIC) comes on, check the
engine oil level right away. For more information,
see CHECK OIL LEVEL underDIC Warnings and
Messages on page 270. You should check the
engine oil level regularly; this is an added reminder.
Checking Engine Oil
It is a good idea to check the engine oil every time
you get fuel. In order to get an accurate reading,
the oil must be warm and the vehicle must be
on level ground.
459

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 473.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.
470