2008 GMC ENVOY Coolant system

{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.
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

6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
7. By this time, the coolant level inside the radiator
ller neck may be lower. If the level is lower, add
more of the proper DEX-COOL
®coolant mixture
through the ller neck until the level reaches the
base of the ller neck.
8. Then replace the pressure cap. At any time during
this procedure if coolant begins to ow out of the
ller neck, reinstall the pressure cap. Be sure
the pressure cap is hand-tight and fully seated.
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions the clutch is not engaged. This improves fuel
economy and reduces fan noise. Under heavy vehicle
loading, trailer towing, and/or high outside temperatures,
the fan speed increases when the clutch engages so
you may hear an increase in fan noise. This is normal
and should not be mistaken as the transmission slipping
or making extra shifts. It is merely the cooling system
functioning properly. The fan will slow down when
additional cooling is not required and the clutch
disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
5-35

Windshield Washer Fluid
What to Use
When you need windshield washer uid, be sure to read
the manufacturer’s instructions before use. If you will
be operating your vehicle in an area where the
temperature may fall below freezing, use a uid that
has sufficient protection against freezing.
Adding Washer Fluid
Open the cap with the
washer symbol on it.
Add washer uid until the
tank is full. SeeEngine
Compartment Overview
on page 5-12for reservoir
location.Notice:
When using concentrated washer uid, follow
the manufacturer’s instructions for adding
water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts
of the washer system. Also, water does not
clean as well as washer uid.
Fill the washer uid tank only three-quarters full
when it is very cold. This allows for uid
expansion if freezing occurs, which could
damage the tank if it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage the vehicle’s
windshield washer system and paint.
5-37

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 5-16. Reset oil life
system. SeeEngine Oil Life System on page 5-19.An Emission Control
Service.••
Visually check for any leaks or damage.See footnote (j).••
Inspect engine air cleaner lter. If necessary, replace lter. SeeEngine Air
Cleaner/Filter on page 5-21.See footnote (k).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 5-72and “Tire Wear Inspection” inAt Least Once a Month on
page 6-9.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid as
needed.••
Perform any needed additional services. See “Additional Required Services” in
this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transmission uid level and add uid as needed.See footnote (g).•
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(e)Make sure the safety belt reminder light and safety
belt assemblies are working properly. Look for any
other loose or damaged safety belt system parts. If you
see anything that might keep a safety belt system
from doing its job, have it repaired. Have any torn or
frayed safety belts replaced. Also see Checking
the Restraint Systems on page 1-68.
(f)Lubricate all key lock cylinders, hood latch assembly,
secondary latch, pivots, spring anchor, release pawl,
rear compartment hinges, outer liftgate handle pivot
points, rear door detent link, roller mechanism, liftgate
handle pivot points, latch bolt, fuel door hinge, cargo
door hinge, locks, and folding seat hardware. More
frequent lubrication may be required when exposed to a
corrosive environment. Applying silicone grease on
weatherstrips with a clean cloth will make them
last longer, seal better, and not stick or squeak.
(g)Inspect hoses for cracks, chafing, leaks, kinks, and
proper installation.(h)Change automatic transmission fluid and filter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police, or delivery
service.
(i)Drain, flush, and refill cooling system. This service
can be complex; you should have your dealer/retailer
perform this service. See Engine Coolant on page 5-26
for what to use. Inspect hoses. Clean radiator,
condenser, pressure cap, and filler neck. Pressure test
the cooling system and pressure cap.
(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid if needed.
(k)If you drive regularly under dusty conditions, inspect
the filter at each engine oil change.
(l)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.
6-8

Owner Checks and Services
These owner checks and services should be performed
at the intervals specied to help ensure the safety,
dependability, and emission control performance of your
vehicle. Your dealer/retailer can assist you with these
checks and services.
Be sure any necessary repairs are completed at once.
Whenever any uids or lubricants are added to your
vehicle, make sure they are the proper ones, as shown
inRecommended Fluids and Lubricants on page 6-12.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel fill.
Engine Oil Level Check
Notice:It is important to check the engine oil
regularly and keep it at the proper level. Failure to
keep the engine oil at the proper level can cause
damage to the engine not covered by your warranty.
Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil on page 5-16.
Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL®
coolant mixture if necessary. SeeEngine Coolant
on page 5-26.
Windshield Washer Fluid Level Check
Check the windshield washer uid level in the windshield
washer uid reservoir and add the proper uid if
necessary.
At Least Once a Month
Tire Ination Check
Inspect your vehicle’s tires and make sure they are
inated to the correct pressures. Do not forget to
check the spare tire. SeeInflation - Tire Pressure on
page 5-64. Check to make sure the spare tire is stored
securely. SeeChanging a Flat Tire on page 5-82.
Tire Wear Inspection
Tire rotation may be required for high mileage highway
drivers prior to the Engine Oil Life System service
notication. Check the tires for wear and, if necessary,
rotate the tires. SeeTire Inspection and Rotation on
page 5-72.
6-9

Recommended Fluids and
Lubricants
Fluids and lubricants identied below by name, part
number, or specication can be obtained from your
dealer/retailer.
Usage Fluid/Lubricant
Engine OilEngine oil which meets
GM Standard GM6094M and
displays the American Petroleum
Institute Certied for Gasoline
Engines starburst symbol. To
determine the proper viscosity for
your vehicle’s engine, seeEngine
Oil on page 5-16.
Engine Coolant50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. SeeEngine Coolant on
page 5-26.
Hydraulic Brake
SystemDelco
®Supreme 11 Brake Fluid or
equivalent DOT-3 brake uid.
Windshield
WasherOptikleen
®Washer Solvent.
Usage Fluid/Lubricant
Parking Brake
Cable GuidesChassis Lubricant
(GM Part No. U.S. 12377985, in
Canada 88901242) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Power Steering
SystemGM Power Steering Fluid
(GM Part No. U.S. 89021184, in
Canada 89021186).
Automatic
TransmissionDEXRON
®-VI Automatic
Transmission Fluid.
Key Lock
CylindersMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241, in
Canada 10953474).
Chassis
LubricationChassis Lubricant
(GM Part No. U.S. 12377985, in
Canada 88901242) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
Front and Rear
AxleSAE 75W-90 Synthetic
Axle Lubricant
(GM Part No. U.S. 89021677,
in Canada 89021678) meeting
GM Specication 9986115.
6-12

Check
Engine Light...............................................3-41
Gages Warning Light...................................3-47
Check Gas Cap Light......................................3-49
Checking Things Under the Hood......................5-10
Chemical Paint Spotting.................................5-106
Child Restraints
Child Restraint Systems...............................1-38
Infants and Young Children...........................1-35
Lower Anchors and Tethers for Children..........1-41
Older Children.............................................1-32
Securing a Child Restraint in a
Rear Outside Seat Position........................1-47
Securing a Child Restraint in the
Center Rear Seat Position.........................1-49
Securing a Child Restraint in the
Right Front Seat Position..........................1-50
Where to Put the Restraint...........................1-40
Chime Level Adjustment.................................3-103
Cigarette Lighter.............................................3-20
Cleaning
Aluminum Wheels......................................5-105
Exterior Lamps/Lenses................................5-104
Fabric/Carpet............................................5-101
Finish Care...............................................5-104
Instrument Panel, Vinyl, and Other
Plastic Surfaces.....................................5-102
Interior.....................................................5-100
Leather....................................................5-102
Tires........................................................5-106Cleaning (cont.)
Underbody Maintenance.............................5-106
Washing Your Vehicle.................................5-103
Weatherstrips............................................5-103
Windshield, Backglass, and Wiper Blades......5-105
Climate Control System
Dual..........................................................3-21
Dual Automatic............................................3-23
Outlet Adjustment........................................3-28
Rear..........................................................3-28
Clock, Setting.................................................3-66
Collision Damage Repair..................................7-12
Compass.......................................2-39, 2-41, 2-44
Content Theft-Deterrent....................................2-16
Control of a Vehicle.......................................... 4-3
Convenience Net............................................2-59
Coolant
Engine Temperature Gage............................3-40
Heater, Engine............................................2-24
Cooling System..............................................5-30
Cruise Control................................................3-11
Cruise Control Light........................................3-46
Customer Assistance Information
Courtesy Transportation................................7-11
Customer Assistance for
Text Telephone (TTY) Users........................ 7-6
Customer Assistance Offices........................... 7-6
Customer Satisfaction Procedure..................... 7-2
GM Mobility Reimbursement Program............... 7-7
Reporting Safety Defects to General Motors....7-16
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