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Engine Oil (Isuzu Diesel Engine)
Checking Engine Oil
It is a good idea to check the engine oil level every time
you get fuel.
The engine oil dipstick is
located in the engine
compartment on the driver
side of the vehicle.In order to get an accurate reading, the engine should
be at normal operating temperature, so that the oil
is warm, and the vehicle must be on level ground.
1. If the engine is at normal operating temperature and
the oil is warm, turn off the engine and allow at
least five minutes for the oil to drain back into the
oil pan. If you do not do this, the oil dipstick
might not show the actual level.
If the engine has not been run long enough to bring
it up to normal operating temperature and the oil
is cool, turn off the engine and allow 30 minutes for
the oil 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 a cloth, then push it back in all the way.
3. Remove the dipstick again, keeping the tip down,
and check the oil level.
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When to Add Engine Oil
Notice:Do not add too much oil. Keep the oil level
between the ADD (C) and FULL (B) marks on the
dipstick. Under normal engine operation, the engine
oil level can increase above the FULL (B) mark as
a result of DPF regeneration. A small increase in the
oil level is normal. If the engine has so much oil
that the oil level reaches the wider portion (A) on the
dipstick, the engine oil must be changed as soon
as possible or the engine could be damaged.
If the oil is below the ADD
mark (C) on the dipstick,
add at least one quart/liter
of the recommended oil.This section explains what kind of oil to use. For engine
oil crankcase capacity, seeCapacities and
Specifications on page 5-102.
Add oil at the engine oil fill
cap in the engine
compartment. Install and
fully tighten the fill cap
when you are through.
Add enough oil to put the level somewhere in the proper
operating range. Push the dipstick all the way back in
when you are through.
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What Kind of Engine Oil to Use
Look for three things:
•CJ-4
Oils designated as API CJ-4 are required for the
vehicle. The CJ-4 designation can appear either alone
or in combination with other American Petroleum
Institute (API) designations, such as API CJ-4/SL.
These letters show API levels of quality.
•SAE 10W-40 or SAE 15W-40
SAE 10W-40 or SAE 15W-40 is best for the
vehicle. When it is very cold, below 0°F (−18°C), use
SAE 5W-40 to improve cold starting. These numbers
on the oil container show its viscosity, or thickness.
Do not use other viscosity oils such as SAE 10W-30
or SAE 20W-50.
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Engine Oil (Gasoline Engine)
If the low oil light appears
on the instrument cluster,
check the engine oil
level right away.
For more information, seeLow Oil Level Light on
page 3-39. You should check the engine oil level
regularly; this is an added reminder.
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.
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When to Add Engine Oil
If the oil is below the cross-hatched area at the tip of the
dipstick, add at least one quart/liter of the recommended
oil. This section explains what kind of oil to use. For
engine oil crankcase capacity, seeCapacities and
Specifications on page 5-102.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.
The engine oil fill cap is
located near the engine
oil dipstick in the engine
compartment, on the driver
side of the vehicle.
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.
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Engine Oil Additives / Engine Oil
Flushes
Do not add anything to the oil. The recommended oils
with the API service symbol are all that is needed
for good performance and engine protection.
Engine oil system flushes are not recommended and
could cause engine damage not covered by the vehicle
warranty.
Engine Oil Life System (Gasoline
Engine)
When to Change Engine Oil
This vehicle has a computer system that indicates when
to change the engine oil and filter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change is indicated can vary considerably.
For the oil life system to work properly, the system
must be reset every time the oil is changed.
When the system has calculated that oil life has been
diminished, it indicates that an oil change is necessary.
A change engine oil light comes on. SeeChangeEngine Oil Light on page 3-39. Change the oil as soon
as possible within the next 600 miles (1 000 km). It
is possible that, if driving under the best conditions, the
oil life system might not indicate that an oil change
is necessary for over a year. However, the engine oil
and filter must be changed at least once a year and at
this time the system must be reset. Your dealer/retailer
has trained service people who will perform this
work using genuine parts and reset the system. It is
also important to check the oil regularly and keep it at
the proper level.
If the system is ever reset accidentally, the oil must be
changed at 3,000 miles (5 000 km) 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
The Engine Oil Life System calculates when to change
the engine oil and filter based on vehicle use. Whenever
the oil is changed, reset the system so it can calculate
when the next oil change is required. If a situation occurs
where the oil is changed prior to a change engine oil light
being turned on, reset the system.
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To reset the change engine oil light:
1. Turn the ignition key to ON/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 the
vehicle is started, the engine oil life system has not
reset. Repeat the procedure.
What to Do with Used Oil
Used engine oil contains certain elements that can 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. Recycle it by taking it to a
place that collects used oil.
Engine Oil Life System
(DURAMAX/Isuzu Diesel Engines)
When to Change Engine Oil
If the vehicle has the Engine Oil Life System, it has a
computer system that indicates 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 is indicated can vary considerably.
For the oil life system to work properly, the system
must be reset every time the oil is changed.
When the system has calculated that oil life has been
diminished, it indicates that an oil change is necessary.
A change engine oil light comes on. SeeChange Engine
Oil Light on page 3-39. Change the 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 driving under the best conditions, the oil life system
might not indicate that an oil change is necessary for over
a year. However, the engine oil and filter must be
changed at least once a year and at this time the system
must be reset. Your dealer/retailer has trained service
people who will perform this work using genuine parts
and reset the system. It is also important to check the oil
regularly and keep it at the proper level.
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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.
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 6-31.
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