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VEHICLE CARE 253
When the system has calculated that
oil life has been diminished, it
indicates that an oil change is
necessary. A CHANGE ENGINE OIL
SOON message comes on. SeeEngine
Oil Messages 0144. Change the oil as
soon as possible within the next
1 000 km (600 mi). It is possible that,
if driving under the best conditions,
the oil life system might indicate that
an oil change is not necessary for up
to a year. The engine oil and filter
must be changed at least once a year
and at this time the system must be
reset. Your dealer has trained service
people who will perform this work and
reset the system. It is also important
to check the oil regularly over the
course of an oil drain interval and
keep it at the proper level.
If the system is ever reset accidentally,
the oil must be changed at 5 000 km
(3,000 mi) since the last oil change.
Remember to reset the oil life system
whenever the oil is changed.How to Reset the Engine Oil Life
System
Reset the system whenever the engine
oil is changed so that the system can
calculate the next engine oil change.
To reset the system:
1. Using the DIC buttons, display REMAINING OIL LIFE on the
DIC. See Driver Information Center
(DIC) 0136 and Engine Oil
Messages 0144.
2. Press and hold SEL to clear the CHANGE ENGINE OIL SOON
message and reset the oil life
at 100%.
Be careful not to reset the oil life
display accidentally at any time
other than after the oil is
changed. It cannot be reset
accurately until the next oil
change.
The oil life system can also be reset as
follows: 1. Turn the ignition on with the engine off. 2. Fully press and release the
accelerator pedal three times
within five seconds.
If the CHANGE ENGINE OIL
SOON message is not on, the
system is reset.
The system is reset when the
CHANGE ENGINE OIL SOON message
is off.
If the CHANGE ENGINE OIL SOON
message comes back on when the
vehicle is started, the engine oil life
system has not been reset. Repeat the
procedure.
Automatic Transmission
Fluid
How to Check Automatic
Transmission Fluid
It is not necessary to check the
transmission fluid level.
A transmission fluid leak is the only
reason for fluid loss. If a leak occurs,
take the vehicle to your dealer and
have it repaired as soon as possible.

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VEHICLE CARE 257
Caution
If improper coolant mixture,
inhibitors, or additives are used in
the vehicle cooling system, the
engine could overheat and be
damaged. Too much water in the
mixture can freeze and crack engine
cooling parts. The repairs would not
be covered by the vehicle warranty.
Use only the proper mixture of
engine coolant for the cooling
system. SeeRecommended Fluids
and Lubricants 0318.
Never dispose of engine coolant by
putting it in the trash, pouring it on
the ground, or into sewers, streams,
or bodies of water. Have the coolant
changed by an authorized service
center, familiar with legal
requirements regarding used coolant
disposal. This will help protect the
environment and your health.
Checking Coolant
The vehicle must be on a level surface
when checking the coolant level.
3.0L V6 Engine Coolant Surge Tank
3.6L V6 Engine Coolant Surge Tank
Check to see if coolant is visible in the
coolant surge tank. If the coolant
inside the coolant surge tank is boiling, do not do anything else until
it cools down. If coolant is visible but
the coolant level mark is not visible,
add a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant at the coolant surge tank to
the top rib on the middle of the tank,
but be sure the cooling system is cool
before this is done. See
Engine
Overheating 0259.
The coolant surge tank is in the
engine compartment on the passenger
side of the vehicle. See Engine
Compartment Overview 0247.
How to Add Coolant to the
Coolant Surge Tank
Caution
This vehicle has a specific coolant
fill procedure. Failure to follow this
procedure could cause the engine to
overheat and be severely damaged.
If no problem is found, check to see if
coolant is visible in the coolant surge
tank. If coolant is visible but the
coolant level is not at the indicated
level mark, add a 50/50 mixture of

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258 VEHICLE CARE
clean, drinkable water and DEX-COOL
coolant at the coolant surge tank, but
be sure the cooling system, including
the coolant surge tank pressure cap, is
cool before you do it.
{Warning
Steam and scalding liquids from a
hot cooling system can blow out
and burn you badly. Never turn the
cap when the cooling system,
including the surge tank pressure
cap, is hot. Wait for the cooling
system and surge tank pressure cap
to cool.
{Warning
Adding only plain water or some
other liquid to the cooling system
can be dangerous. Plain water and
other liquids, can boil before the
proper coolant mixture will. The
coolant warning system is set for
the proper coolant mixture. With(Continued)
Warning (Continued)
plain water or the wrong mixture,
the engine could get too hot but
you would not get the overheat
warning. The engine could catch
fire and you or others could be
burned. Use a 50/50 mixture of
clean, drinkable water and
DEX-COOL coolant.
Caution
In cold weather, water can freeze
and crack the engine, radiator,
heater core, and other parts. Use
the recommended coolant and the
proper coolant mixture.
{Warning
You can be burned if you spill
coolant on hot engine parts.
Coolant contains ethylene glycol(Continued)
Warning (Continued)
and it will burn if the engine parts
are hot enough. Do not spill coolant
on a hot engine.
1. Remove the coolant surge tank pressure cap when the cooling
system, including the coolant
surge tank pressure cap and
upper radiator hose, is no
longer hot.
Turn the pressure cap slowly
counterclockwise about
one-quarter of a turn. If you hear
a hiss, wait for that to stop. This
will allow any pressure still left
to be vented out the
discharge hose.
2. Keep turning the pressure cap slowly and remove it.
3. Fill the coolant surge tank with the proper mixture to the
indicated level mark.
4. With the coolant surge tank pressure cap off, start the engine
and let it run until you can feel

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VEHICLE CARE 271
Number Usage21 A/C clutch
22 –
23 Coolant heater control module
24 Coolant pump
25 Coolant pump relay
26 Hi fuel
27 Steering column lock
28 Rear heated seats
29 Front heated seats
30 –
31 LED LGT battery
32 A/C control module
33 AIR solenoid
34 –
35 Engine control module
36 Engine control module 2
37 Coolant pump/ Ignition coils –odd Number Usage
38 Ignition coils –even/
Non walk 2
39 Non walk
40 Instrument cluster
41 –
42 Fuel pump power module
43 Instrument panel body/Ignition
44 Aeroshutter
45 Washer
46 Front sensor
47 Left cornering LED
48 AIR solenoid relay
49 Air pump relay
50 Engine control module relay
51 Wiper speed relay
52 Wiper control relay
53 Headlamp control relay
54 – Number Usage
55 –
56 Air pump
57 –
58 Instrument panel electronic center
59 –
60 ABS pump
61 Front wiper
62 Headlamp leveling
63 Electric brake booster module
64 –
65 –
66 Transfer case control module
67 Electric brake booster
68 Rear seat entertainment
display
69 RESS coolant pump
70 –
71 ABS valve

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SERVICE AND MAINTENANCE 311
checks and services. The Additional
Required Services - Normal are for
vehicles that:
.Carry passengers and cargo within
recommended limits on the Tire
and Loading Information label. See
Vehicle Load Limits 0191.
. Are driven on reasonable road
surfaces within legal driving limits.
. Use the recommended fuel. See
Fuel 0240.
Refer to the information in the
Maintenance Schedule Additional
Required Services - Normal chart.
The Additional Required Services -
Severe are for vehicles that are:
. Mainly driven in heavy city traffic
in hot weather.
. Mainly driven in hilly or
mountainous terrain.
. Frequently towing a trailer.
. Used for high speed or competitive
driving.
. Used for taxi, police, or delivery
service. Refer to the information in the
Maintenance Schedule Additional
Required Services - Severe chart.
{Warning
Performing maintenance work can
be dangerous and can cause serious
injury. Perform maintenance work
only if the required information,
proper tools, and equipment are
available. If they are not, see your
dealer to have a trained technician
do the work. See
Doing Your Own
Service Work 0245.
Maintenance Schedule
Owner Checks and Services
At Each Fuel Stop
.
Check the engine oil level. See
Engine Oil 0250.
Once a Month
. Check the tire inflation pressures.
See Tire Pressure 0279.
. Inspect the tires for wear. See Tire
Inspection 0284.
. Check the windshield washer fluid
level. See Washer Fluid 0260.
Engine Oil Change
Change the engine oil and filter when
the CHANGE ENGINE OIL SOON
message displays, 12 000 km/7,500 mi,
or at one year, whichever comes first.
If driven under the best conditions,
the engine oil life system may not
indicate the need for vehicle service
for up to a year. The engine oil and
filter must be changed at least once a
year and the oil life system must be
reset. Your trained dealer technician
can perform this work. If the engine

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312 SERVICE AND MAINTENANCE
oil life system is reset accidentally,
service the vehicle within 5 000 km/
3,000 mi since the last service. Reset
the oil life system when the oil is
changed. SeeEngine Oil Life
System 0252.
Tire Rotation and Required
Services Every 12 000 km/
7,500 mi
Rotate the tires, if recommended for
the vehicle, and perform the following
services. See Tire Rotation0284.
. Check engine oil level and oil
life percentage. If needed, change
engine oil and filter, and reset oil
life system. See Engine Oil0250
and Engine Oil Life System 0252.
. Check engine coolant level. See
Engine Coolant 0256.
. Check windshield washer fluid
level. See Washer Fluid 0260.
. Visually inspect windshield wiper
blades for wear, cracking,
or contamination. See Exterior
Care 0301. Replace worn or
damaged wiper blades. See Wiper
Blade Replacement 0265. .
Check tire inflation pressures. See
Tire Pressure 0279.
. Inspect tire wear. See Tire
Inspection 0284.
. Visually check for fluid leaks.
. Inspect engine air cleaner filter.
See Engine Air Cleaner/Filter 0254.
. Inspect brake system. See Exterior
Care 0301.
. Visually inspect steering,
suspension, and chassis
components for damaged, loose,
or missing parts or signs of wear.
See Exterior Care 0301.
. Check restraint system
components. See Safety System
Check 072.
. Visually inspect fuel system for
damage or leaks.
. Visually inspect exhaust system
and nearby heat shields for loose
or damaged parts.
. Lubricate body components. See
Exterior Care 0301.
. Check starter switch. See Starter
Switch Check 0264. .
Check automatic transmission
shift lock control function. See
Automatic Transmission Shift Lock
Control Function Check 0264.
. Check parking brake and
automatic transmission park
mechanism. See Park Brake and
P (Park) Mechanism Check 0265.
. Check accelerator pedal for
damage, high effort, or binding.
Replace if needed.
. Visually inspect gas strut for signs
of wear, cracks, or other damage.
Check the hold open ability of the
strut. See your dealer if service is
required.
. Inspect sunroof track and seal,
if equipped. See Sunroof052.

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SERVICE AND MAINTENANCE 313
Maintenance Schedule
Additional Required Services -
Normal12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi
60 000 km/37,500 mi
72 000 km/45,000 mi
84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi
120 000 km/75,000 mi
132 000 km/82,500 mi
144 000 km/90,000 mi
156 000 km/97,500 mi
168 000 km/105,000 mi
180 000 km/112,500 mi
192 000 km/120,000 mi
204 000 km/127,500 mi
216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 mi
Rotate tires, if recommended for the vehicle, and
perform Required Services. Check engine oil level
and oil life percentage. Change engine oil and filter,
if needed. (1)@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Replace passenger compartment air filter. (2)@ @@@@@
Inspect evaporative control system. (3)@ @@
Replace engine air cleaner filter. (4)@ @ @ @ @ @ @ @ @ @
Replace spark plugs. Inspect spark plug wires. (3.0L
Twin Turbo Engine)@ @
Replace spark plugs. Inspect spark plug wires. (3.6L
Engine)@
Drain and fill engine cooling system. (5)@
Change transfer case fluid. (6)@
Change front and rear axle fluid.@
Visually inspect accessory drive belts. (7)@
Replace brake fluid. (8)

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314 SERVICE AND MAINTENANCE
Footnotes—Maintenance Schedule
Additional Required Services -
Normal
(1) Vehicles with different size front
and rear tires do not have tire
rotation. See Tire Rotation0284.
(2) Or every two years, whichever
comes first. More frequent passenger
compartment air filter replacement
may be needed if driving in areas with
heavy traffic, poor air quality, high
dust levels, or environmental
allergens. Passenger compartment air
filter replacement may also be needed
if there is reduced airf low, window
fogging, or odors. Your GM dealer can
help determine when to replace the
filter. (3)
Visually check all fuel and vapor
lines and hoses for proper attachment,
connection, routing, and condition.
(4) Or every two years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
(5) Or every five years, whichever
comes first. See Cooling System0255.
(6) Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water can
overcome the seals and contaminate
the transfer case fluid. Contaminated
fluid will decrease the life of the
transfer case and/or axles and should
be replaced. (7)
Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(8) Replace brake fluid every five
years. See Brake Fluid 0262.