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ENGINE COMPARTMENT — 3.0L DIESEL
1 — Air Cleaner Filter5 — Battery
2 — Engine Oil Dipstick 6 — Power Distribution Center (PDC)
3 — Engine Oil Fill 7 — Washer Fluid Reservoir
4 — Brake Fluid Reservoir 8 — Engine Coolant
124 MAINTAINING YOUR VEHICLE
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•Do not change the thermostat for Summer or Winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory engine coolant (antifreeze)
performance, poor gas mileage, and increased emis-
sions.
Charge Air Cooler — Inter-Cooler
The charge air cooler is positioned in front of the radiator
and the air conditioner condenser. Air enters the engine
through the air cleaner and passes through the turbo-
charger, where it is pressurized. This pressurized air
rapidly reaches high temperature. The air is then directed
through a hose to the charge air cooler and through
another hose to the intake manifold of the engine. This
cooling process enables more efficient burning of fuel
resulting in fewer emissions. To guarantee optimum performance of the system, keep
the surfaces of the charge air cooler, condenser and
radiator clean and free of debris. Periodically check the
hoses leading to and from the charge air cooler for cracks
or loose clamps resulting in loss of pressure and reduced
engine performance.
Brake System
Brake Master Cylinder — Brake Fluid Level Check
The fluid level of the master cylinder should be checked
when performing under the hood service, or immedi-
ately if the “Brake System Warning Light” indicates
system failure.
The brake master cylinder has a translucent plastic
reservoir. On the outboard side of the reservoir, there is a
“MAX” mark and a “MIN” mark. The fluid level must be
kept within these two marks. Do not add fluid above the
full mark because leakage may occur at the cap.
144 MAINTAINING YOUR VEHICLE
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MAINTENANCE SCHEDULE
Your vehicle is equipped with an automatic oil change
indicator system. The oil change indicator system will
remind you that it is time to take your vehicle in for
scheduled maintenance.
Based on engine operation conditions, the oil change
indicator message will illuminate. This means that ser-
vice is required for your vehicle. Operating conditions
such as frequent short-trips, trailer tow, extremely hot or
cold ambient temperatures will influence when the “Oil
Change Required” message is displayed. Severe Operat-
ing Conditions can cause the change oil message to
illuminate as early as 3,500 miles (5,600 km) since last
reset. Have your vehicle serviced as soon as possible,
within the next 500 miles (805 km).
Your authorized dealer will reset the oil change indicator
message after completing the scheduled oil change. If a
scheduled oil change is performed by someone otherthan your authorized dealer, the message can be reset by
referring to the steps described under “Electronic Vehicle
Information Center (EVIC)” or “Driver Information Dis-
play (DID)” in “Understanding Your Instrument Panel”
for further information.
NOTE:
Under no circumstances should oil change inter-
vals exceed 10,000 miles (16,000 km) or twelve months,
whichever comes first.
Once A Month Or Before A Long Trip:
• Check engine oil level
• Check windshield washer fluid level
• Check the tire inflation pressures and look for unusual
wear or damage
• Check the fluid levels of the coolant reservoir, brake
master cylinder and power steering, and fill as needed
• Check function of all interior and exterior lights
152 MAINTENANCE SCHEDULE
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ENGINE COMPARTMENT — 6.7L DIESEL — SIX-SPEED 68RFE (2500/3500 Models)
1 — Battery7 — Washer Fluid Reservoir
2 — Engine Coolant Reservoir 8 — Power Steering Fluid Reservoir
3 — Automatic Transmission Dipstick 9 — Power Distribution Center
4 — Brake Fluid Reservoir 10 — Engine Oil Dipstick
5 — Battery 11 — Engine Oil Fill
6 — Aux Power Distribution Center 12 — Air Cleaner Filter7
MAINTAINING YOUR VEHICLE 333
Page 336 of 406
ENGINE COMPARTMENT — 6.7L DIESEL — SIX-SPEED AS69RC HD (3500/CHASSIS CAB MODELS)
1 — Battery7 — Washer Fluid Reservoir
2 — Engine Coolant Reservoir 8 — Power Steering Fluid Reservoir
3 — Automatic Transmission Dipstick 9 — Power Distribution Center
4 — Brake Fluid Reservoir 10 — Engine Oil Dipstick
5 — Battery 11 — Engine Oil Fill
6 — Aux Power Distribution Center 12 — Air Cleaner Filter
334 MAINTAINING YOUR VEHICLE
Page 362 of 406

•Do not change the thermostat for Summer or Winter
operation. If replacement is ever necessary, install
ONLY the correct type thermostat. Other designs may
result in unsatisfactory engine coolant (antifreeze)
performance, poor gas mileage, and increased emis-
sions.
Charge Air Cooler — Inter-Cooler
The charge air cooler is positioned below the radiator and
the air conditioner condenser. Air enters the engine
through the air cleaner and passes through the turbo-
charger, where it is pressurized. This pressurized air
rapidly reaches high temperature. The air is then directed
through a hose to the charge air cooler and through
another hose to the intake manifold of the engine. The air
entering the engine has been cooled by about 50° to 100°F
(10° to 38°C). This cooling process enables more efficient
burning of fuel resulting in fewer emissions. To guarantee optimum performance of the system, keep
the surfaces of the charge air cooler, condenser and
radiator clean and free of debris. Periodically check the
hoses leading to and from the charge air cooler for cracks
or loose clamps resulting in loss of pressure and reduced
engine performance.
Brake System
Brake Master Cylinder — Brake Fluid Level Check
The fluid level of the master cylinder should be checked
when performing under the hood service, or immedi-
ately if the “Brake System Warning Light” indicates
system failure.
The brake master cylinder has a translucent plastic
reservoir. On the outboard side of the reservoir, there is a
“MAX” mark and a “MIN” mark. The fluid level must be
kept within these two marks. Do not add fluid above the
full mark because leakage may occur at the cap.
360 MAINTAINING YOUR VEHICLE
Page 382 of 406
MAINTENANCE SCHEDULE — DIESEL ENGINE
CAUTION!
Failure to perform the required maintenance items
may result in damage to the vehicle.
At Each Stop For Fuel
Check the engine oil level at least 30 minutes after a fully
warmed engine is shut off. Checking the oil level while
the vehicle is on level ground will improve the accuracy
of the oil level reading. Add oil only when the level is at
or below the ADD or MIN mark.
Once A Month
• Inspect the batteries, and clean and tighten the termi-
nals as required. •
Check the fluid levels of the coolant reservoir, brake
master cylinder, and automatic transmission (if
equipped), and add as needed.
At Each Oil Change
• Change the engine oil filter.
• Inspect the exhaust system.
• Inspect engine air filter.
• Check the coolant level, hoses, and clamps.
• Lubricate outer tie rod ends.
Inspection and service should also be performed anytime
a malfunction is observed or suspected. Retain all re-
ceipts.
380 MAINTENANCE SCHEDULE