2003 GMC ENVOY radiator cap

Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of Your
Vehicle......................................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Speci®cations....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
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...................................................5-15
Engine Air Cleaner/Filter................................5-20
Automatic Transmission Fluid.........................5-21
Engine Coolant.............................................5-24
Radiator Pressure Cap..................................5-26
Engine Overheating.......................................5-27
Cooling System............................................5-29
Engine Fan Noise.........................................5-35
Power Steering Fluid.....................................5-36
Windshield Washer Fluid................................5-37Brakes........................................................5-38
Battery........................................................5-41
Jump Starting...............................................5-42
Rear Axle.......................................................5-48
Four-Wheel Drive............................................5-48
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps..................................................5-50
Front Turn Signal and Sidemarker Lamps........5-51
Taillamps and Turn Signal Lamps...................5-51
Replacement Bulbs.......................................5-52
Windshield Wiper Blade Replacement..............5-52
Tires..............................................................5-54
In¯ation -- Tire Pressure................................5-55
Tire Inspection and Rotation...........................5-55
When It Is Time for New Tires.......................5-57
Buying New Tires.........................................5-58
Uniform Tire Quality Grading..........................5-59
Wheel Alignment and Tire Balance..................5-60
Wheel Replacement......................................5-60
Tire Chains..................................................5-62
Accessory In¯ator.........................................5-62
If a Tire Goes Flat........................................5-64
Changing a Flat Tire.....................................5-64
Section 5 Service and Appearance Care
5-1

A. Coolant Recovery Tank. SeeEngine Coolant on
page 5-24.
B. Engine Air Cleaner/Filter. See
Engine Air
Cleaner/Filter on page 5-20.
C. Windshield Washer Fluid Reservoir. See
Windshield
Washer Fluid on page 5-37.
D. Power Steering Fluid Reservoir. See
Power Steering
Fluid on page 5-36.
E. Automatic Transmission Dipstick. See
Automatic
Transmission Fluid on page 5-21.
F. Engine Oil Dipstick. See
Engine Oil on page 5-15.G. Radiator Pressure Cap. See
Radiator Pressure Cap
on page 5-26.
H. Engine Oil Fill Cap. See
Engine Oil on page 5-15.
I. Remote Negative (-) Terminal Marked GND.
See
Jump Starting on page 5-42.
J. Brake Master Cylinder. See
Brakes on page 5-38.
K. Battery. See
Battery on page 5-41.
L. Engine Compartment Fuse Block. See ªEngine
Compartment Fuse Blockº under
Fuses and Circuit
Breakers on page 5-90.
5-13

A. Coolant Recovery Tank. SeeEngine Coolant on
page 5-24.
B. Engine Air Cleaner/Filter. See
Engine Air
Cleaner/Filter on page 5-20.
C. Windshield Washer Fluid Reservoir. See
Windshield
Washer Fluid on page 5-37.
D. Engine Oil Dipstick. See
Engine Oil on page 5-15.
E. Automatic Transmission Dipstick. See
Automatic
Transmission Fluid on page 5-21.
F. Engine Oil Fill Cap. See
Engine Oil on page 5-15.
G. Radiator Pressure Cap. See
Radiator Pressure Cap
on page 5-26.
H. Remote Negative (-) Terminal Marked GND. See
Jump Starting on page 5-42.
I. Power Steering Fluid Reservoir. See
Power Steering
Fluid on page 5-36.
J. Brake Master Cylinder. See
Brakes on page 5-38.
K. Engine Compartment Fuse Block. See ªEngine
Compartment Fuse blockº under
Fuses and Circuit
Breakers on page 5-90.
L. Battery. See
Battery on page 5-41.
Engine Oil
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It's a good idea to check your 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.
The engine oil dipstick
handle is a yellow ring
located in the engine
compartment toward the
passenger's side of
the vehicle. See
Engine
Compartment Overview on
page 5-12
for more
information on location.
Turn off the engine and give the oil several minutes to
drain back into the oil pan. If you don't, the oil
dipstick might not show the actual level.
Pull out the dipstick and clean it with a paper towel or
cloth, then push it back in all the way. Remove it again,
keeping the tip down, and check the level.
5-15

Adding Coolant
If you need more coolant, add the proper DEX-COOLž
coolant mixtureat the coolant recovery tank.
{CAUTION:
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will
almost never have to add coolant at the
radiator. Never turn the radiator pressure
cap Ð even a little Ð when the engine and
radiator are hot.
Add coolant mixture at the recovery tank, but be careful
not to spill it.
{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. Don't spill coolant on a hot engine.
Occasionally check the coolant level in the radiator. For
information on how to add coolant to the radiator,
see
Cooling System on page 5-29.
Radiator Pressure Cap
Notice:Your pressure cap is a pressure-type cap
and must be tightly installed to prevent coolant loss
and possible engine damage from overheating.
See ªCapacities and Speci®cationsº for more
information.
See
Engine Compartment Overview on page 5-12for
information on location.
5-26

Cooling System
When you decide it's safe to lift the hood, here's what
you'll see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Engine Fan
If the coolant inside the coolant recovery tank is boiling,
don't do anything else until it cools down. The vehicle
should be parked on a level surface. L6 Engine
V8 Engine
5-29

The coolant level should
be at least up to the FULL
COLD mark. If it isn't,
you may have a leak at the
pressure cap or in the
radiator hoses, heater
hoses, radiator, water
pump or somewhere else
in the cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Don't touch them. If you
do, you can be burned.
Don't run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine ®re, and you could be
burned. Get any leak ®xed before you drive the
vehicle.If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal
down. If it doesn't, your vehicle needs service. Turn off
the engine.
Notice:Engine damage from running your engine
without coolant isn't covered by your warranty.
Notice:When adding coolant, it is important that
you use only DEX-COOLž(silicate-free) coolant.
If coolant other than DEX-COOLžis added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the engine
coolant will require change sooner Ð at 30,000 miles
(50 000 km) or 24 months, whichever occurs ®rst.
Damage caused by the use of coolant other
than DEX-COOL
žis not covered by your new vehicle
warranty.
5-30

When the coolant in the coolant recovery tank is at the
FULL COLD mark, start your vehicle.
If the overheat warning continues, there's one more
thing you can try. You can add the proper coolant
mixture directly to the radiator, but be sure the cooling
system is cool before you do it.
{CAUTION:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They
are under pressure, and if you turn the radiator
pressure cap -- even a little -- they can come
out at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap, is hot. Wait for the cooling system and
radiator pressure cap to cool if you ever have
to turn the pressure cap.
5-32

How to Add Coolant to the Radiator
1. You can remove the radiator pressure cap when
the cooling system, including the radiator pressure
cap and upper radiator hose, is no longer hot.
Turn the pressure cap slowly counterclockwise
about one full turn.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.2. Then keep turning the pressure cap. Remove the
pressure cap.
5-33