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WARNING!
•The warning words “DO NOT OPEN HOT” on
the cooling system pressure cap are a safety pre-
caution. Never add engine coolant (antifreeze)
when the engine is overheated. Do not loosen or
remove the cap to cool an overheated engine. Heat
causes pressure to build up in the cooling system.
To prevent scalding or injury, do not remove the
pressure cap while the system is hot or under
pressure.
•Do not use a pressure cap other than the one
specified for your vehicle. Personal injury or en-
gine damage may result.
Disposal Of Used Engine Coolant
Used ethylene glycol based engine coolant (antifreeze) is
a regulated substance requiring proper disposal. Check
with your local authorities to determine the disposalrules for your community. To prevent ingestion by ani-
mals or children, do not store ethylene glycol based
engine coolant (antifreeze) in open containers or allow it
to remain in puddles on the ground. If ingested by a child
or pet, seek emergency assistance immediately. Clean up
any ground spills immediately.
Coolant Level
The coolant bottle provides a quick visual method for
determining that the coolant level is adequate. With the
engine cold, the level of the engine coolant (antifreeze) in
the coolant recovery bottle should be between the ranges
indicated on the bottle.
The radiator normally remains completely full, so there is
no need to remove the radiator cap unless checking for
engine coolant (antifreeze) freeze point or replacing en-
gine coolant (antifreeze). Advise your service attendant
6
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of this. As long as the engine operating temperature is
satisfactory, the coolant bottle need only be checked once
a month.
When additional engine coolant (antifreeze) is needed to
maintain the proper level, it should be added to the
coolant bottle. Do not overfill.
Points To Remember
NOTE:When the vehicle is stopped after a few miles (a
few kilometers) of operation, you may observe vapor
coming from the front of the engine compartment. This is
normally a result of moisture from rain, snow, or high
humidity accumulating on the radiator and being vapor-
ized when the thermostat opens, allowing hot engine
coolant (antifreeze) to enter the radiator.
If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
•Do not overfill the coolant recovery bottle.
•Check the engine coolant (antifreeze) freeze point in
the radiator and in the coolant recovery bottle. If
engine coolant (antifreeze) needs to be added, the
contents of the coolant recovery bottle must also be
protected against freezing.
•If frequent engine coolant (antifreeze) additions are
required, or if the level in the coolant recovery bottle
does not drop when the engine cools, the cooling
system should be pressure tested for leaks.
•Maintain engine coolant (antifreeze) concentration at
50% HOAT engine coolant (antifreeze) (minimum)
and distilled water for proper corrosion protection of
your engine, which contains aluminum components.
•Make sure that the radiator and coolant recovery
bottle overflow hoses are not kinked or obstructed.
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•Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean.
•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 cooling performance, poor gas
mileage, and increased emissions.
Charge Air Cooler – Inter-Cooler
The charge air cooler is positioned between 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.6
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The brake master cylinder has a translucent plastic
reservoir. On the outboard side of the reservoir, there is a
“MAX” mark and an “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.
With disc brakes, the fluid level can be expected to fall as
the brake linings wear. However, an unexpected drop in
fluid level may be caused by a leak and a system check
should be conducted.
Refer to “Fluids, Lubricants, and Genuine Parts” in
“Maintaining Your Vehicle” for further information.WARNING!
•Use only manufacturer’s recommended brake
fluid. Refer to “Fluids, Lubricants, and Genuine
Parts” in “Maintaining Your Vehicle” for further
information. Using the wrong type of brake fluid
can severely damage your brake system and/or
impair its performance. The proper type of brake
fluid for your vehicle is also identified on the
original factory installed hydraulic master cylin-
der reservoir.(Continued)
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WARNING! (Continued)
•To avoid contamination from foreign matter or
moisture, use only new brake fluid or fluid that
has been in a tightly closed container. Keep the
master cylinder reservoir cap secured at all times.
Brake fluid in a open container absorbs moisture
from the air resulting in a lower boiling point.
This may cause it to boil unexpectedly during hard
or prolonged braking, resulting in sudden brake
failure. This could result in a accident.
•Overfilling the brake fluid reservoir can result in
spilling brake fluid on hot engine parts, causing
the brake fluid to catch fire. Brake fluid can also
damage painted and vinyl surfaces, care should be
taken to avoid its contact with these surfaces.(Continued)
WARNING! (Continued)
•Do not allow petroleum based fluid to contami-
nate the brake fluid. Brake seal components could
be damaged, causing partial or complete brake
failure. This could result in an accident.
Clutch Hydraulic System
The clutch hydraulic system is a sealed maintenance-free
system. In the event of leakage or other malfunction, the
system must be replaced.
Transfer Case – If Equipped
Drain And Refill
Refer to the “Maintenance Schedule” for the proper
maintenance intervals.
Lubricant Selection
Refer to “Fluids, Lubricants, and Genuine Parts” in
“Maintaining Your Vehicle” for further information.
6
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Fluid Level Check
This fluid level can be checked by removing the filler
plug. The fluid level should be to the bottom edge of the
filler plug hole with the vehicle in a level position.
Manual Transmission – If Equipped
Lubricant Selection
Refer to “Fluids, Lubricants, and Genuine Parts” in
“Maintaining Your Vehicle” for further information.
Fluid Level Check
The fluid level can be checked by removing the filler
plug. If the level of the lubricant is more than 1/2 in
(12 mm) below the bottom of the filler hole while the
vehicle is on level ground, enough lubricant should be
added to bring the level to 1/4 in (6 mm) below the
bottom of the filler hole.
Automatic Transmission – If Equipped
Lubricant Selection
Refer to “Fluids, Lubricants, and Genuine Parts” in
“Maintaining Your Vehicle” for further information.
Fluid Level Check – Ram Truck Only
The fluid level should be checked when the engine is
fully warmed up and the fluid in the transmission is at
normal operating temperature. At normal operating tem-
perature, the fluid cannot be held comfortably between
the fingertips. Operation of the transmission with an
improper fluid level will greatly reduce the life of the
transmission and of the fluid. Check the fluid level
whenever the vehicle is serviced.
To properly check the automatic transmission fluid level,
the following procedure must be used:
1. Operate the engine at idle speed and normal operating
temperature.
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2. The vehicle must be on level ground.
3. Fully apply the parking brake and press the brake
pedal.
4. Place the shift lever momentarily into each gear posi-
tion ending with the shift lever in PARK.
5. Remove the dipstick, wipe it clean and reinsert it until
seated.
6. Remove the dipstick again and note the fluid level on
both sides. The fluid level should be between the “HOT”
(upper) reference holes on the dipstick at normal operat-
ing temperature. Verify that solid coating of oil is seen on
both sides of the dipstick. If the fluid is low, add as
required into the dipstick tube.Do not overfill.After
adding any quantity of oil through the oil fill tube, wait
a minimum of two minutes for the oil to fully drain into
the transmission before rechecking the fluid level. NOTE:
If it is necessary to check the transmission below
the operating temperature, the fluid level should be
between the two “COLD” (lower) holes on the dipstick
with the fluid at approximately 70°F (21°C) (room tem-
perature). If the fluid level is correctly established at
room temperature, it should be between the “HOT”
(upper) reference holes when the transmission reaches
180°F (82°C). Remember it is best to check the level at the
normal operating temperature.
CAUTION!
Be aware that if the fluid temperature is below 50°F
(10°C) it may not register on the dipstick. Do not add
fluid until the temperature is elevated enough to
produce an accurate reading.
7. Check for leaks. Release parking brake.6
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To prevent dirt and water from entering the transmission
after checking or replenishing fluid, make certain that the
dipstick cap is properly reseated. It is normal for the
dipstick cap to spring back slightly from its fully seated
position, as long as its seal remains engaged in the
dipstick tube.
Fluid Level Check – Chassis Cab Only
Check the fluid level while the transmission is at normal
operating temperature. This occurs after at least 15 miles
(25 km) of driving. At normal operating temperature, the
fluid cannot be held comfortably between the fingertips.
To properly check the transmission fluid, the following
procedure must be used.
1. The vehicle must be on level ground.
2. Operate the engine at idle speed for a minimum of
60 seconds and normal operating temperature.3. Fully apply the parking brake and press the brake
pedal.
4. Place the shift lever momentarily into each gear posi-
tion ending with the shift lever in PARK. Make sure the
engine is running at idle speed.
5. Remove the dipstick and determine if the fluid is hot
or cold. Hot fluid is approximately 160°F to 175°F (70°C
to 82°C). This is the normal operating temperature after
the vehicle has been driven at least 15 miles (25 km). The
fluid cannot be comfortably held between the fingertips.
Only use the cold region of the dipstick as a rough
reference when doing initial oil level set after transmis-
sion rebuild or transmission refill.
6. Wipe the dipstick clean and reinsert it until seated.
126 MAINTAINING YOUR VEHICLE