2005 GMC ENVOY DENALI heating

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 can not see or smell CO. It can cause
unconsciousness or death. SeeEngine
Exhaust on page 2-34. To maximize your safety
when towing a trailer:
Have your exhaust system inspected for
leaks and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
CAUTION: (Continued)
CAUTION: (Continued)

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.
SeeDual Climate Control System on
page 3-21orDual Automatic Climate
Control System on page 3-23.
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.
4-63

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 gearbeforeyou 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 THIRD (3) or a lower gear, under heavy
loads or hilly conditions.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If you turn your
engine off immediately after towing at high altitude 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
automatic transmission in PARK (P) for a few minutes
before turning the engine off. If you do get the overheat
warning, seeEngine Overheating on page 5-28.
4-65

Service............................................................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside
of Your Vehicle...........................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.......................5-9
Checking Things Under the Hood....................5-10
Hood Release..............................................5-10
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-16
Engine Oil Life System..................................5-19
Engine Air Cleaner/Filter................................5-20
Automatic Transmission Fluid.........................5-22
Engine Coolant.............................................5-25
Radiator Pressure Cap..................................5-28
Engine Overheating.......................................5-28
Cooling System............................................5-30Engine Fan Noise.........................................5-35
Power Steering Fluid.....................................5-36
Windshield Washer Fluid................................5-36
Brakes........................................................5-37
Battery........................................................5-41
Jump Starting...............................................5-42
Rear Axle.......................................................5-47
Four-Wheel Drive............................................5-48
Front Axle......................................................5-48
Bulb Replacement..........................................5-49
Halogen Bulbs..............................................5-49
Headlamps, Front Turn Signal, Sidemarker,
and Parking Lamps....................................5-50
Taillamps, Turn Signal, and Stoplamps............5-50
Back-Up Lamps............................................5-51
Replacement Bulbs.......................................5-51
Windshield Wiper Blade Replacement..............5-52
Tires..............................................................5-54
Tire Sidewall Labelling...................................5-55
Tire Terminology and Denitions.....................5-58
Ination - Tire Pressure.................................5-61
Tire Inspection and Rotation...........................5-62
When It Is Time for New Tires.......................5-64
Section 5 Service and Appearance Care
5-1

How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmission uid to use. SeeRecommended
Fluids and Lubricants on page 6-12.
Add uid only after checking the transmission uid while
it is hot. A cold check is used only as a reference.
If the uid level is low, add only enough of the proper
uid to bring the level up to the HOT area for a hot
check. It does not take much uid, generally less than
one pint (0.5 L).Do not overll.
Notice:Use of automatic transmission uid labeled
other than DEXRON
®-III, Approved for the
H-Specication, may damage your vehicle, and the
damages may not be covered by your warranty.
Always use automatic transmission uid labeled
DEXRON
®-III, Approved for the H-Specication.
After adding uid, recheck the uid level as
described under “How to Check,” earlier in
this section.
When the correct uid level is obtained, push the
dipstick back in all the way; then ip the handle
down to lock the dipstick in place.
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 5-28.
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 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.
5-25

Radiator 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.
SeeEngine Compartment Overview on page 5-12for
information on location.
Engine Overheating
You will nd a coolant temperature gage on your
vehicle’s instrument panel. If your vehicle has a Driver
Information Center (DIC), the display will show an
Engine Coolant Hot or Engine Overheated message.
SeeDIC Warnings and Messages on page 3-55
for more information.
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
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.
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.
5-28

Backglass Wiper Blade Replacement
SeeWindshield Wiper Blade Replacement on page 5-52
for instructions on how to change the backglass wiper
blade. The backglass wiper blade will not lock in a
vertical position like the windshield wiper blade, so care
should be used when pulling it away from the vehicle.
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. SeeLoading Your
Vehicle on page 4-44.
Underinated 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. SeeInflation - Tire
Pressure on page 5-61.
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 your tread is badly worn, or if your tires
have been damaged, replace them.
5-54

Accessory Inator
Your vehicle may be equipped with an accessory
inator system. You can inate things like basketballs
and bicycle tires. You can also use it to bring your
tire pressure up to the proper pressure. It is not
designed to inate large objects which will require more
than ve minutes to inate, such as an air mattress.
The accessory inator is
located in the rear
compartment on the
driver’s side of the vehicle
behind an access cover,
near the liftgate opening.
To remove the cover, push in on the tab to access
the inator.
You may have an air inator kit that is located in the
glove compartment. It includes a 22 ft (6.7 m) hose with
three nozzle adapters.To use the accessory inator, do the following:
1. Attach the appropriate nozzle adapter to the end of
the hose if required.
2. Attach that end of the hose to the object you wish
to inate.
3. Attach the other end of the hose to the outlet.
4. Press and release the switch to turn the air inator
on. The indicator light will remain on when the
inator is running.
The system has an internal clock to prevent
overheating. The system will allow about ve minutes
of running time, then the compressor will stop. The
indicator light will then begin to ash. When the
indicator is off, the inator can be started again by
pressing the switch. If the compressor is still hot, it
may only run for a short time before shutting
off again.
5. Press and release the switch to turn the inator off.
Place the inator kit tools in the pouch and store it in
its proper location. Remove the inator hose from
the outlet during loading and unloading. Load leveling
will not function with the inator hose attached to
the inator outlet. See “Electronically Controlled Air
Suspension System” underLoading Your Vehicle
on page 4-44
5-69

E
Electrical System
Add-On Equipment......................................5-96
Engine Compartment Fuse Block...................5-97
Fuses and Circuit Breakers...........................5-97
Headlamps.................................................5-96
Power Windows and Other Power Options......5-96
Rear Underseat Fuse Block.........................5-106
Windshield Wiper Fuses...............................5-96
Engine
Air Cleaner/Filter.........................................5-20
Battery.......................................................5-41
Change Engine Oil Light...............................3-46
Check and Service Engine Soon Light............3-42
Coolant......................................................5-25
Coolant Heater............................................2-21
Coolant Temperature Gage...........................3-41
Engine Compartment Overview......................5-12
Exhaust.....................................................2-34
Fan Noise..................................................5-35
Oil .............................................................5-16
Overheating................................................5-28
Reduced Power Light...................................3-47
Starting......................................................2-20
Entry Lighting.................................................3-19
Event Data Recorders (EDR)............................7-10
Exit Lighting...................................................3-19
Extender, Safety Belt.......................................1-26
F
Filter
Engine Air Cleaner......................................5-20
Finish Damage...............................................5-93
Fixed Mast Antenna.......................................3-139
Flash-to-Pass................................................... 3-8
Flat Tire........................................................5-70
Flat Tire, Changing.........................................5-71
Flat Tire, Storing.............................................5-82
Fluid
Automatic Transmission................................5-22
Power Steering...........................................5-36
Windshield Washer......................................5-36
Fog Lamps....................................................3-17
Four-Wheel Drive....................................2-26, 5-48
Front Axle......................................................5-48
Fuel............................................................... 5-5
Additives...................................................... 5-6
California Fuel.............................................. 5-5
Check Gas Cap Light...................................3-51
Filling a Portable Fuel Container..................... 5-9
Filling Your Tank........................................... 5-7
Fuels in Foreign Countries.............................. 5-6
Gage.........................................................3-50
Gasoline Octane........................................... 5-5
Gasoline Specications.................................. 5-5
Low Warning Light.......................................3-51
5