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To reset the Engine Oil Life System, do the
following:
1. Turn the ignition key to RUN with the
engine off.
2. Fully press and release the accelerator pedal
slowly three times within 10 seconds.
If the change engine oil light flashes for
five seconds, the system is resetting.
3. Turn the key to OFF.
If the change engine oil light comes back on when
you start your vehicle, the Engine Oil Life
System has not reset. Repeat the procedure.
What to Do with Used Oil
Used engine oil contains certain elements that may
be unhealthy for your skin and could even cause
cancer. Do not let used oil stay on your skin for very
long. Clean your skin and nails with soap and
water, or a good hand cleaner. Wash or properly
dispose of clothing or rags containing used engine
oil. See the manufacturer’s warnings about the use
and disposal of oil products.Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil
from the filter before disposal. Never dispose of oil
by putting it in the trash, pouring it on the
ground, into sewers, or into streams or bodies of
water. Instead, recycle it by taking it to a place
that collects used oil. If you have a problem
properly disposing of your used oil, ask your
dealer, a service station, or a local recycling
center for help.
Engine Oil Life System
(Caterpillar
®Diesel Engine)
How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to
change your engine oil and filter based on vehicle
use. Anytime your oil is changed, reset the
system so it can calculate when the next oil
change is required. If a situation occurs where you
change your oil prior to a change engine oil light
being turned on, reset the system.
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Engine Coolant (Gas and
DURAMAX
®/Isuzu Engines)
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your vehicle for five years or
150,000 miles (240 000 km), whichever occurs
first, 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 288.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.
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What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not be
covered by your warranty. Too much water
in the mixture can freeze and crack the engine,
radiator, heater core, and other parts.
If you have to add coolant more than four times a
year, have your dealer check your cooling system.
Notice:If you use extra inhibitors and/or
additives in your vehicle’s cooling system, you
could damage your vehicle. Use only the
proper mixture of the engine coolant listed in
this manual for the cooling system. See
Part C: Recommended Fluids and Lubricants
on page 397for more information.
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If the low coolant
warning light comes on
in the instrument
panel cluster and stays
on, it means you are
low on engine coolant.
SeeLow Coolant Warning Light on page 173for
further information.
Adding Coolant
If you need more coolant, add the proper
DEX-COOL®coolant mixture at the surge tank,
but only when the engine is cool.
{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. Do not spill
coolant on a hot engine.
When replacing the pressure cap, make sure it is
hand-tight and fully seated.
Engine Coolant
(Caterpillar
®Diesel Engines)
If your vehicle has a Caterpillar®diesel engine,
see the Caterpillar®Diesel Engine Operation
& Maintenance Manual provided with your vehicle
to find out what to add, as well as when and
how to service your cooling system.
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Coolant Surge Tank Pressure Cap
The coolant surge tank pressure cap is located in
the engine compartment, on the driver’s side of
the vehicle.
Notice:Your vehicle’s surge tank pressure cap
is designed for use with medium-duty cooling
systems only. If the surge tank pressure cap is
not tightly installed, coolant loss and possible
engine damage may occur. Be sure the cap is
properly and tightly secured.
Engine Overheating
You will find an engine coolant temperature gage,
as well as a low coolant warning light, on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 173andLow Coolant
Warning Light on page 173for more information.
Your vehicle also has a check gages warning light
on the instrument panel. SeeCheck Gages
Warning Light on page 180for 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.
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If No Steam Is Coming From
Your Engine
An overheat warning, along with a low coolant light,
can indicate a serious problem. SeeLow Coolant
Warning Light on page 173for more information.
If you get an engine overheat warning with no low
coolant light, but see or hear no steam, the
problem may not be too serious. Sometimes the
engine can get a little too hot when you:
•Climb a long hill on a hot day.
•Stop after high-speed driving.
•Idle for long periods in traffic.
If you get the overheat warning with no sign of
steam, try this for a minute or so:
1. In heavy traffic, let the engine idle in
NEUTRAL while stopped. If it is safe to do so,
pull off the road, shift to PARK (P) or
NEUTRAL and let the engine idle.
2. Turn on your heater to full hot at the highest
fan speed and open the windows as
necessary.
3. If climbing a hill, downshift to raise engine and
fan speeds.If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not come
back on, you can drive normally.
If the warning continues and you have not
stopped, pull over, stop, and park your vehicle
right away.
If there is still no sign of steam, you can push
down the accelerator until the engine speed is
about twice as fast as normal idle speed for at least
three minutes while you are parked. If you still have
the warning, turn off the engine and get everyone
out of the vehicle until it cools down.
You may decide not to lift the hood but to get
service help right away.
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If no coolant is visible in the surge tank, add
coolant as follows:
{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 coolant surge tank pressure
cap — even a little — they can come out at
high speed. Never turn the cap when the
cooling system, including the coolant
surge tank pressure cap, is hot. Wait for
the cooling system and coolant surge
tank pressure cap to cool if you ever have
to turn the pressure cap.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice: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.
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Power Steering Fluid
SeeScheduled Maintenance on page 363to
determine when to check your power steering fluid.
How To Check Power Steering Fluid
Check your power steering fluid only when the
engine is warm. If the engine is not warm, you
probably will not get an accurate reading.
If the fluid level is between the MIN (Minimum) and
MAX (Maximum) marks, you have enough. If you
need fluid, add only enough of the proper fluid to
bring it in between the MIN and MAX marks.
If your power steering fluid level is low, this can
cause the brake or service brakes soon warning
lights to come on. In addition, the steering
effort and emergency brake distance could
increase.If either light remains on after you have added
power steering fluid to the proper level, then shut
off the engine for 10 seconds. This should
reset the brake warning lights. If one or both lights
stay on, see “Hydraulic Brake System Warning
Lights” underBrake System Warning Light
on page 169for more information.
What to Use
To determine what kind of fluid to use, see
Part C: Recommended Fluids and Lubricants on
page 397.
Notice:When adding power steering uid or
making a complete uid change, always
use the proper uid. Failure to use the proper
uid can cause leaks and damage hoses
and seals.
295