2004 GMC YUKON XL DENALI overheating

Adding Coolant
If you need more coolant, add the proper DEX-COOLž
coolant mixtureat the surge tank, but only when the
engine is cool.
{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.
Coolant Surge Tank Pressure Cap
The coolant surge tank pressure cap must be fully
installed on the coolant surge tank. SeeEngine
Compartment Overview on page 5-12for more
information on location.
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.
Engine Overheating
You will ®nd a coolant temperature gage on your
vehicle's instrument panel. SeeEngine Coolant
Temperature Gage on page 3-38. In addition, you will
®nd an ENGINE COOLANT HOT, ENGINE
OVERHEATED and a REDUCED ENGINE POWER
message in the DIC on the instrument panel. See
DIC
Warnings and Messages on page 3-57.
Overheated Engine Protection
Operating Mode
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. See
Engine Oil on
page 5-13.
5-25

If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
you badly, even if you just open the hood. Stay
away from the engine if you see or hear steam
coming from it. Just turn it off and get
everyone away from the vehicle until it cools
CAUTION: (Continued)
CAUTION: (Continued)
down. Wait until there is no sign of steam or
coolant before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch ®re.
You or others could be badly burned. Stop
your engine if it overheats, and get out of the
vehicle until the engine is cool.
See ªOverheated Engine Protection Operating
Modeº under
Engine Overheating on page 5-25
for information on driving to a safe place in an
emergency.
Notice:If your engine catches ®re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty. See ªOverheated
Engine Protection Operating Modeº under
Engine
Overheating on page 5-25for information on driving
to a safe place in an emergency.
5-26

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's Owner's Manual.
{CAUTION:
Poorly maintained and improperly used tires
are dangerous.
·Overloading your tires can cause
overheating as a result of too much
friction. You could have an air-out and a
serious accident. See ªLoading Your
Vehicleº in the Index.
·Underin¯ated tires pose the same danger
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 tires are cold.
CAUTION: (Continued)
CAUTION: (Continued)
·
Overin¯ated tires are more likely to be
cut, punctured or broken by a sudden
impact Ð such as when you hit a pothole.
Keep tires at the recommended pressure.
·Worn, old tires can cause accidents.
If your tread is badly worn, or if your tires
have been damaged, replace them.
Tire Sidewall Labeling
Useful information about a tire is molded into the
sidewall. The following illustrations are examples of a
typical P-Metric and a LT-Metric tire sidewall.
5-54

Door (cont.)
Programmable Automatic Door Locks.............2-10
Rear Door Security Locks.............................2-12
Driver
Position, Safety Belt.....................................1-30
DRIVER DOOR AJAR.....................................3-58
Driver Information Center (DIC).........................3-46
DIC Operation and Displays..........................3-46
DIC Warnings and Messages........................3-57
Driving
At Night.....................................................4-28
City...........................................................4-32
Defensive..................................................... 4-2
Drunken....................................................... 4-2
Freeway.....................................................4-33
Hill and Mountain Roads..............................4-35
In Rain and on Wet Roads...........................4-29
Winter........................................................4-37
Driving Across an Incline..................................4-24
Driving Downhill..............................................4-23
Driving in Mud, Sand, Snow or Ice....................4-26
Driving in Water..............................................4-27
Driving On Grades..........................................4-60
Driving on Off-Road Hills.................................4-20
Driving on Snow or Ice....................................4-38
Driving Through Deep Standing Water...............4-31
Driving Through Flowing Water.........................4-31
Driving Uphill..................................................4-21
Driving with a Trailer.......................................4-58
Dual Automatic Climate Control System.............3-20DVD
Cleaning the Video Screen...........................3-99
Distortion....................................................3-97
Rear Seat Entertainment System...................3-80
DVD Player....................................................3-80
E
Easy Exit Seat...............................................2-50
Electrical System
Add-On Equipment.....................................5-103
Fuses and Circuit Breakers.........................5-103
Power Windows and Other Power Options....5-103
Windshield Wiper Fuses.............................5-103
Emissions Inspection and Maintenance
Programs...................................................3-42
Engine
Air Cleaner/Filter.........................................5-18
Battery.......................................................5-39
Check and Service Engine Soon Light............3-40
Coolant......................................................5-23
Coolant Heater............................................2-21
Coolant Temperature Gage...........................3-38
Engine Compartment Overview......................5-12
Exhaust.....................................................2-30
Fan Noise..................................................5-33
Oil .............................................................5-13
Overheating................................................5-25
Starting......................................................2-19
5