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If the system is ever reset accidentally, you must
change your oil at 3,000 miles (5 000 km)
since your last oil change. Remember to reset the
oil life system whenever the oil is changed.
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.
To reset the change engine oil light, 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.
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Engine Oil Life System
(DURAMAX
®Diesel)
When to Change Engine Oil
If your vehicle has the Engine Oil Life System, it
has a computer system that lets you know when to
change the engine oil and filter. This is based
on injection timing, engine load and engine
temperature, and not on mileage. Based on driving
conditions, the mileage at which an oil change
will be indicated can vary considerably. For the oil
life system to work properly, you must reset the
system every time the oil is changed.
When the system has calculated that oil life has
been diminished, it will indicate that an oil change
is necessary. A change engine oil light will
come on. SeeChange Engine Oil Light on
page 176. Change your oil as soon as possible
within the next 600 miles (1 000 km) or 30 hours of
engine operation, whichever occurs first. It is
possible that, if you are driving under the best
conditions, the oil life system may not indicate that
an oil change is necessary for over a year.However, your engine oil and filter must be
changed at least once a year and at this time the
system must be reset. Your dealer has
GM-trained service people who will perform this
work using genuine GM parts and reset the
system. It is also important to check your oil
regularly and keep it at the proper level.
If the system is ever reset accidentally, you must
change your oil at 15,000 miles (24 000 km),
or 150 hours of engine operation, whichever
occurs first, since your last oil change. Remember
to reset the oil life system whenever the oil is
changed.
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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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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To reset the Engine Oil Life System, do the
following:
1. Turn the ignition key to RUN with the
engine off.
2. Fully apply and hold the brake pedal while
you fully press and release the accelerator
pedal, pausing slightly at each press and each
release, three times within five seconds.
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.
Engine Air Cleaner/Filter
The engine air
cleaner/filter is located
in the center of the
engine compartment.
When to Inspect the Engine Air
Cleaner/Filter
If your vehicle has an
air cleaner/filter change
indicator, inspect the
indicator at every
oil change and replace
the filter when the
indicator tells you to.
For vehicles without a change indicator, inspect
the air cleaner/filter at every oil change and
replace the filter at the first oil change after
25,000 miles (40 000 km).
How to Inspect the Engine Air
Cleaner/Filter
Locate the filter change indicator. When the
change indicator turns black or is in the red/orange
change area, replace the filter and reset the
indicator.
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To inspect the engine air cleaner/filter, remove the
filter from the vehicle and lightly shake the filter
to release loose dust and dirt. If the filter remains
caked with dirt, a new filter is required.
{CAUTION:
Operating the engine with the air cleaner/
lter off can cause you or others to be
burned. The air cleaner not only cleans the
air; it helps to stop ames if the engine
back res. If it is not there and the engine
back res, you could be burned. Do not
drive with it off, and be careful working on
the engine with the air cleaner/ lter off.
Notice:If the air cleaner/ lter is off, a back re
can cause a damaging engine re. And, dirt
can easily get into your engine, which will
damage it. Always have the air cleaner/ lter in
place when you are driving.
Hood Inlet Seal
If your vehicle is being used in heavy snow
conditions or for snow plowing, there is a
possibility of snow and ice build up in the inlet to
the air cleaner, blocking airflow to the engine
and negatively impacting engine performance.
To prevent the blocking of air, remove the
hood inlet seal, by doing the following:
1. Loosen the clamp that holds the seal to the
air cleaner.
2. Slide Seal off.
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3. Store the seal in the inlet, located on the
underside of the hood
4. Store the clamp on the coolant surge tank.
Pull the overflow tube out of the white
plastic retainer, slip the clamp over and
reinstall the hose.
The seal will need to be replaced on to the air
cleaner for normal driving, especially in the
warmer months.
Automatic Transmission Fluid
When to Check
A good time to check your automatic transmission
fluid level is when the engine oil is checked.
See your Allison Automatic Transmission
Operator’s Manual to find out when to change
your transmission fluid and filters.
How to Check and What to Use
The Allison Automatic Transmission Operator’s
Manual that came with the vehicle shows how to
check the automatic transmission fluid and
what fluid to use.
Automatic Transmission External Filter
Your automatic transmission filter requires
periodic replacement.
Consult the Allison Automatic Transmission
Operator’s Manual that came with the vehicle for
proper change intervals.
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Manual Transmission Fluid
When to Check
A good time to have it checked is when the
engine oil is checked. Refer to the Maintenance
Schedule to find out when to check and change
your manual transmission fluid. SeeScheduled
Maintenance on page 363.
How to Check and What to Use
Check the fluid level only when your engine is off,
the vehicle is parked on a level place, and the
transmission is cool enough for you to rest
your fingers on the transmission case.
To check the transmission fluid level, do the
following:
1. Remove the filler plug.
2. Check to be sure that the lubricant level is up
to the bottom of the fill opening. On heavy
duty transmissions, an inch of oil level equals
about one gallon of fluid.3. If the fluid level is good, reinstall the plug and
be sure it is fully seated. If the fluid level is
low, add more fluid as described in the
next steps. Refer to the Maintenance
Schedule to determine what kind of fluid to
use. SeePart C: Recommended Fluids
and Lubricants on page 397.
How to Add Fluid
To add transmission fluid, do the following:
1. Remove the filler plug.
2. Add fluid at the filler plug hole. Add only
enough fluid to bring the fluid level up to
the bottom of the fill opening. Refer to
the Maintenance Schedule to determine the
proper fluid to use. SeePart C:
Recommended Fluids and Lubricants on
page 397.
3. Reinstall the filler plug. Be sure the plug is
fully seated.
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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.
284