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The engine idle speed will return to normal once
the following conditions are met:
•Once engine coolant temperature reaches
about 150°F (65°C).
•The intake temperature reaches a
certain level.
The high idle speed will be temporarily interrupted
and the engine speed will return to normal if
any of the following conditions occur:
•The brake pedal is applied.
•The accelerator pedal is pressed.
•The automatic transmission is shifted out of
PARK (P) or NEUTRAL (N).
•The clutch pedal on the manual transmission
is pressed.
•Vehicle speed is detected.
Once these conditions no longer exist, the engine
idle speed will slowly increase to high idle after
the normal delay, if the conditions for engine
coolant temperature and air intake temperature
are still met.
Engine Checks Before Operating
When you have started your engine, let it run for
20 to 30 seconds before you put a load on the
engine. But do not leave the vehicle while
the engine is running.
Avoid unnecessary idling of diesel engine
equipped vehicles.
If the engine idles too long, the temperature of the
engine coolant will fall below the normal operating
range. Low engine operating temperature
causes several conditions which affect engine
operation and reduce engine life.
The engine should be permitted to go through a
warm-up period. Operate the vehicle at a minimum
of 600 rpm during the warm-up period. During
this period and during operation, the following
observations should be made.
During this warm-up period, check your warning
lights and gages:
•If oil pressure does not begin to rise within
15 seconds of starting, stop the engine
and find the cause. SeeOil Pressure Gage on
page 175for more information.
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Engine Coolant Temperature Gage............ 173
Low Coolant Warning Light....................... 173
Wait to Start Indicator............................... 174
Malfunction Indicator Lamp........................ 174
Oil Pressure Gage..................................... 175
Low Oil Level Light................................... 176
Change Engine Oil Light........................... 176
Engine Overspeed Warning Light.............. 177
Engine Shutdown Warning Light................ 177
Transmission Temperature Gage............... 178
Exhaust Brake Indicator Light.................... 178
Differential Lock Indicator Light.................. 178
Reduced Engine Power Light.................... 179
Highbeam On Light................................... 179
Daytime Running Lamps (DRL)
Indicator Light........................................ 179
Low Washer Fluid Warning Light............... 180
Check Gages Warning Light...................... 180
Fuel Gage................................................. 181Water in Fuel Warning Light...................... 182
Air Filter Restriction Indicator..................... 182
Air Pressure Gage..................................... 183
Hourmeter Gage........................................ 183
Audio System(s)......................................... 184
Setting the Time........................................ 185
AM-FM Radio............................................ 186
Radio with Cassette.................................. 189
Radio with CD........................................... 195
Theft-Deterrent Feature
(Non-RDS Radios)................................. 201
Radio Reception........................................ 201
Care of the Cassette Tape Player............. 202
Care of Your CDs..................................... 203
Care of the CD Player.............................. 204
Fixed Mast Antenna.................................. 204
Chime Level Adjustment............................ 204
Section 3 Instrument Panel
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Oil Pressure Gage
The engine oil pressure gage, on the lower right
portion of your instrument panel cluster, shows
engine oil pressure in psi (pounds per square inch)
or in kPa (kilopascals). Oil pressure may vary
with outside temperature and oil viscosity,
but readings of 30 to 40 psi (205 to 275 kPa) on
gasoline engines at operating temperature
and moderate road speeds are normal. If you
have a diesel engine, the normal operating range
should be between 35 and 70 psi (240 to 480 kPa).A reading in the low pressure zone may be
caused by a dangerously low oil level or other
problem.
If you have a Caterpillar
®diesel engine, also see
your Caterpillar®Operation & Maintenance
Manual.
{CAUTION:
Do not keep driving if the oil pressure is
low. If you do, your engine can become so
hot that it catches re. You or others
could be burned. Check your oil as soon
as possible and have your vehicle
serviced.
Notice:Lack of proper engine oil maintenance
may damage the engine. The repairs would
not be covered by your warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
United StatesCanada
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Low Oil Level Light
Your vehicle may have
a low oil level light.
This light should come on as a check, when you
start your engine. If the light fails to come on, have
it repaired as soon as possible so you will be
aware when the oil level is low.
Vehicles that have Caterpillar
®diesel engines may
not have a low oil level light. In this case, the light
will neither come on as a check when you start your
engine, nor will it come on to indicate a low oil level.
If this light comes on and stays on, it means your
engine is low on oil. You need to check the oil level
right away. SeeEngine Oil (Caterpillar
®DieselEngine) on page 268orEngine Oil (Gasoline
Engine) on page 268orEngine Oil (DURAMAX
®/
Isuzu Diesel Engine) on page 272for further
information.
Notice:Lack of proper engine oil maintenance
may damage the engine. The repairs would
not be covered by your warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
Change Engine Oil Light
The change engine oil
light should come on
briefly as a bulb
check when you start
the engine. If the
light does not come on,
have it serviced.
If the change engine oil light comes on and stays
on after you start the engine, have the oil
changed.
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Transmission Temperature Gage
If you have an automatic
transmission and this
gage, it is located above
the switchbank in the
center of the instrument
panel.
When your ignition is on, the gage shows the
temperature of the transmission oil. A reading in
the warning zone, the red area beginning at 300°F
(150°C), means you must stop driving and
check into the cause. One possible cause is a low
oil level in the transmission.
Notice:If you drive your vehicle with the
transmission temperature gage above normal
operating range, you can damage the
transmission. This could lead to costly repairs
that would not be covered by your warranty.
Do not drive your vehicle while the
transmission temperature gage reading is
above normal. See your dealer for service.
Exhaust Brake Indicator Light
If your vehicle is
equipped with an
exhaust brake, you will
have this light, located
above the climate
controls in the center of
the instrument panel.
The exhaust brake indicator light will come on and
stay on whenever the diesel engine exhaust brake
or exhaust restrictor is active. For more information,
seeDiesel Engine Exhaust Brake on page 112and
Exhaust Restrictor (Engine Warm-Up) on page 108.
Differential Lock Indicator Light
If your vehicle has this
feature, this light is
located in the center of
the instrument panel.
The light is on when the
rear differential lock
system is in use.
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When you tilt the hood far enough, the cables will
support it. When you close the hood, make
sure both latches are secured.
Engine Oil (Caterpillar®Diesel
Engine)
See your Caterpillar®Operation & Maintenance
Manual for information on oil quality and viscosities
as well as the temperature range chart.
Engine Oil (Gasoline Engine)
If the low oil light
appears on the
instrument cluster, it
means you need
to check the engine oil
level right away.
For more information, seeLow Oil Level Light on
page 176.
You should check the engine oil level regularly;
this is an added reminder.
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Checking Engine Oil
It is a good idea to check the 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 is located in the
engine compartment
on the driver’s side
of the vehicle.
1. Turn off the engine and give the oil several
minutes to drain back into the oil pan. If you
do not do this, the oil dipstick might not
show the actual level.
2. 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.
When to Add Engine Oil
If the oil is below the cross-hatched area at the tip
of the dipstick, you will need to add at least one
quart/liter of oil. But you must use the right
kind. This section explains what kind of oil to use.
For engine oil crankcase capacity, seeCapacities
and Speci cations on page 347.
Notice:Do not add too much oil. If the engine
has so much oil that the oil level gets above the
cross-hatched area that shows the proper
operating range, the engine could be damaged.
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The engine oil fill cap is
located near the engine
oil dipstick in the
engine compartment, on
the driver’s side of
the vehicle.
Be sure to add enough oil to put the level
somewhere in the proper operating range in the
cross-hatched area. Push the dipstick all the
way back in when you are through.What Kind of Engine Oil to Use
Look for two things:
•GM6094M
Your vehicle’s engine requires oil meeting
GM Standard GM6094M. You should look for
and use only an oil that meets GM Standard
GM6094M.
270