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If the system is ever reset accidentally, the oil must be
changed at 15,000 miles (24 000 km), or 150 hours
of engine operation, whichever occurs first, 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 oil is changed prior to a change engine oil light
being turned on, reset the system.
To reset the Engine Oil Life System:
1. Turn the ignition key to ON/RUN with the
engine off.
2. Fully press and release the accelerator pedal slowly
three times within five seconds.
If the change engine oil light is turned off, 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.
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Engine Oil Life System (Caterpillar
Diesel Engine)
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.
To reset the Engine Oil Life System:
1. Turn the ignition key to ON/RUN with the
engine off.
2. Fully apply and hold the brake pedal while fully
pressing and releasing 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 the
vehicle is started, the Engine Oil Life System has
not reset. Repeat the procedure.
Engine Air Cleaner/Filter
Duramax Diesel 6.6L
EngineV8 Gas, Caterpillar and
Isuzu 6H Diesel
Engines
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When to Inspect the Engine Air
Cleaner/Filters
For vehicle with this feature, the engine air filter life
gage will be located in the engine compartment either
on or near the air cleaner or above the switchbank in the
center of the instrument panel. It monitors the engine
air filter and indicates when the filter should be replaced.
If driving in dusty/dirty conditions, inspect the filter
each oil change.
As the filter gets dirty, the yellow indicator begins to
rise. When it reaches the red/orange change area,
replace the filter. Reset the indicator after each filter
replacement, refer toAir Filter Restriction Indicator
on page 3-46.
How to Inspect the Engine Air
Cleaner/Filter (Duramax Diesel
6.6L Engine)
{CAUTION:
Operating the engine with the air cleaner/filter off
can cause you or others to be burned. The air
cleaner not only cleans the air; it helps to stop
flames if the engine backfires. If it is not there and
the engine backfires, you could be burned. Do not
drive with it off, and be careful working on the
engine with the air cleaner/filter off.
Notice:If the air cleaner/filter is off, a backfire can
cause a damaging engine fire. And, dirt can easily get
into the engine, which will damage it. Always have
the air cleaner/filter in place when you are driving.
The engine air cleaner/filter is located in the center of
the engine compartment.
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.
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How to Inspect the Engine Air Cleaner/
Filters (Gas V8 8.1L, Caterpillar 7.2L and
Isuzu 7.8L Diesel Engines)
{CAUTION:
Operating the engine with the air cleaner/filter off
can cause you or others to be burned. The air
cleaner not only cleans the air; it helps to stop
flames if the engine backfires. If it is not there and
the engine backfires, you could be burned. Do not
drive with it off, and be careful working on the
engine with the air cleaner/filter off.
Notice:If the air cleaner/filter is off, a backfire can
cause a damaging engine fire. And, dirt can easily get
into the engine, which will damage it. Always have
the air cleaner/filter in place when you are driving.
The engine air cleaner/filter is located in the center of
the engine compartment.To inspect the engine air cleaner/filter:
1. Disconnect the air
compressor hose by
pinching the connector
ring to release the
connector lock.
2. Unclip the four clips that hold the upper housing to
the lower housing and remove the upper housing.
3. 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.
4. Reinstall the upper housing and make sure that the
air compressor hose is reconnected by pushing the
connector back onto the port. Listen for the
connector to click to be sure that the air compressor
hose is securely locked and connected. Isuzu 7.8L Diesel Only
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4. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the
engine cooling fan.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge tank
until the level reaches slightly above the FULL
COLD mark.
5. Then replace the pressure cap. Be sure the
pressure cap 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.
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.
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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 3-34andLow Coolant Warning Light on
page 3-35for more information.
Your vehicle also has a check gages warning light on
the instrument panel. SeeCheck Gages Warning
Light on page 3-43for 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.
CAUTION: (Continued)
CAUTION: (Continued)
If you keep driving when your engine is overheated,
the liquids in it can catch fire. 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 the engine catches fire because of being
driven with no coolant, your vehicle can be badly
damaged. The costly repairs would not be covered
by the vehicle warranty.
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 3-35for 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.
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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 3-31for more information.
What to Use
To determine what kind of fluid to use, seePart C:
Recommended Fluids and Lubricants on page 6-31.
Notice:When adding power steering fluid or
making a complete fluid change, always use the
proper fluid. Failure to use the proper fluid can
cause leaks and damage hoses and seals.
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to read
the manufacturer’s instructions before use. If you will
be operating your vehicle in an area where the
temperature may fall below freezing, use a fluid that has
sufficient protection against freezing.
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Four-Wheel Disc Brakes
(Hydraulic Only)
The vehicle has four-wheel disc brakes.
Some driving conditions or climates can cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
the brakes.
Brake linings should always be replaced as complete
axle sets.
Four-Wheel and Six-Wheel Drum
Brakes (Air Only)
The brake drums should be removed and inspected
each time the tires are removed for rotation or changing.
When the front brakes are replaced, have the rear
brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
Brake Pedal Travel
See your dealer/retailer if the brake pedal does not
return to normal height, or if there is a rapid increase in
pedal travel. This could be a sign that brake service
might be required.
Brake Adjustment
Every brake stop, the brakes adjust for wear.
Brake Adjustment on Air Braked Vehicles
The vehicle has automatic slack adjusters. Every
brake stop, the brakes automatically adjust for wear.
Slack adjusters should never be manually adjusted
to correct excessive brake chamber pushrod stroke.
Excessive brake chamber pushrod stroke means
that the brake system needs to be serviced by a
qualified service technician.
Notice:Do not manually adjust automatic slack
adjusters. Manual adjustment of the automatic slack
adjusters can result in a degradation of the slack
adjuster performance over time. If the brake
chamber pushrod stroke is out of adjustment, the
brake system needs to be serviced by a qualified
service technician.
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