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 3-38.
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 3,000 miles (5 000 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.
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.
5-31
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.
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 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.
5-32
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).
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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.
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 ame 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.
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 6-5.
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 6-32.
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 6-32.
3. Reinstall the filler plug. Be sure the plug is
fully seated.
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Rear Axle Shift Motor
When to Check and Change Fluid
If you have an optional air-shift two-speed, controlled
traction, or locking differential type rear axle, a good time
to check the fluid level in the axle shift motor is when
the rear axle lubricant is checked. Use refrigerant
oil (shift motor only).
How to Check Fluid
Remove the plug on the front plate of the axle shift
motor, add enough fluid to raise the level to the bottom
of the filler plug hole, then replace the plug.
What to Use
Refer to your Maintenance Schedule to determine what
kind of lubricant to use. SeePart C: Recommended
Fluids and Lubricants on page 6-32.
Four-Wheel Drive
Transfer Case
When to Check Lubricant
It is not necessary to regularly check transfer case fluid
unless you suspect there is a leak or you hear an
unusual noise. A fluid loss could indicate a problem.
Have it inspected and repaired.
How to Check Lubricant
A. Fill Plug
B. Drain Plug
To get an accurate reading, the vehicle should be on a
level surface.
If the level is below the bottom of the fill plug hole,
located on the transfer case, you’ll need to add some
lubricant. Add enough lubricant to raise the level to
the bottom of the fill plug hole. Use care not to
overtighten the plug.
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Secondary Fuel Filter and Water
Separator/Heater
(Caterpillar
®Diesel)
If you have a Caterpillar®
diesel engine, you may
also have this spin-on filter
and fuel separator/heater.
It will be mounted in
the engine compartment
on the driver’s side of
the vehicle.
It has a metal drain bowl at the bottom. Occasionally,
check the bowl for any water or particles.
To check or drain the bowl, do the following:
•Shut off the engine.
•Push up on the spring loaded drain valve until clear
fuel is flowing from the valve.
The particles or water will drain out first. SeeEngine Oil
(Caterpillar
®Diesel Engine) on page 5-22orEngine
Oil (DURAMAX®Diesel) on page 5-22orEngine
Oil (Gasoline Engine) on page 5-26for proper disposal
procedures.
Automatic Ether Injection System
(Caterpillar
®Diesel)
If you have a Caterpillar®
diesel engine, you may
have this feature. The
ether cylinder is located in
the engine compartment
on the driver’s side of
the vehicle.
To change an empty ether cylinder, follow these steps.
1. Loosen the screw head on the
cylinder-to-bracket clamp.
2. Spread the clamp apart.
3. Clean any dirt from the neck of the cylinder and the
top of the valve before you take out the cylinder.
4. Check the inside of the valve for any foreign matter.
Clean the valve as necessary.
5. Cover the valve to protect it from dirt and take out
the cylinder.
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