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Driving
ConditionLoadTurbocharger
TemperatureIdle Time
(min.) Before
Engine
Shutdown
Stop and Go Empty Cool Less than
One
Stop and Go Medium One
Highway
SpeedsMedium Warm Two
City Traffic Maximum
GCWRThree
Highway
SpeedsMaximum
GCWRFour
Uphill Grade Maximum
GCWRHot Five
Engine Speed Control
CAUTION!
Prevent overspeeding the engine going down hill.
When descending steep grades, use a combination of
gears and service brakes to control vehicle/engine
speed. Overspeed can cause severe engine damage.
Operating Precautions
Avoid Overheating The Engine
The temperature of the coolant (a mixture of 50%
ethylene-glycol and 50% water) must not exceed the
normal range of the temperature gauge (240°F/116°C)
with a 16 psi (110 kPa) radiator cap.
Usually the coolant temperature indicated during opera-
tion will be to the left of center in the normal range of the
gauge.
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Avoid Low Coolant Temperature Operation
Continual operation at low coolant temperature below
the normal range on the gauge (140°F/60°C) can be
harmful to the engine. Low coolant temperature can
cause incomplete combustion which allows carbon and
varnish to form on piston rings and injector nozzles.
Also, the unburned fuel can enter the crankcase, diluting
the lubricating oil and causing rapid wear to the engine.
Cooling System Tips — Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
•City Driving —
when stopped, put transmission in neutral and increase
engine idle speed.
•Highway Driving —
reduce your speed.
•Up Steep Hills —
select a lower transmission gear, but try and keep the
torque converter locked.
•Air Conditioning —
turn it off temporarily.
Do Not Operate The Engine With Low Oil
Pressure
When the engine is at normal operating temperature, the
minimum oil pressures required are:
Idle 700 to 800 RPM............ 10psi(69kPa)
Full speed and load............ 30psi(207 kPa)
CAUTION!
If oil pressure falls to less than normal readings, shut
the engine off immediately. Failure to do so could
result in immediate and severe engine damage.
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Do Not Operate The Engine With Failed Parts
Practically all failures give some warning before the parts
fail. Be on the alert for changes in performance, sounds,
and visual evidence that the engine requires service.
Some important clues are:
•engine misfiring or vibrating severely
•sudden loss of power
•unusual engine noises
•fuel, oil or coolant leaks
•sudden change, outside the normal operating range, in
the engine operating temperature
•excessive smoke
•oil pressure drop
TRANSMISSION SHIFTING
Automatic Transmission with Overdrive— If
Equipped
The gear shift selector display, located in the instrument
panel cluster, indicates the transmission gear range (the
selector is illuminated for night driving). The selector
lever is mounted on the right side of the steering column.
You must depress the brake pedal, to pull the selector
lever out of park (P) position (Brake Interlock System). To
drive, move the selector lever from Park or Neutral to the
desired drive position. Pull the selector lever toward you
when shifting into Reverse, Second, First or Park, or
when shifting out of Park.
Gear Ranges
DO NOT race the engine when shifting from Park or
Neutral position into another gear range.
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Never operate the engine with oil level below the “ADD”
mark or above the upper “SAFE” mark.
Change Engine Oil
CAUTION!
Overfilling or underfilling the crankcase will cause
oil aeration or loss of oil pressure. This could dam-
age your engine.
Road conditions as well as your kind of driving affect the
interval at which your oil should be changed. Check the
following to determine if any apply to you:
•Frequent short trips where the engine does not achieve
full operating temperature (operating temperature de-
fined as 190° F (66° C) coolant temperature).
•Extensive engine idling (over 10 minutes per hour of
operation) at ambient temperatures less than 32° F (0°
C).
•Driving in dusty conditions.
•Frequent trailer towing.
•Taxi, police, or delivery service (commercial service).
•Off-road or desert operation.
•Extensive operation at high engine speeds (greater
than 2900 rpm) and loads (greater than 70% throttle).
IfANYof these apply to you, then change your engine oil
at every interval shown in scheduleBof theMainte-
nance Schedulessection of this manual.
If none of these apply to you, then change your engine oil
at every interval shown on scheduleAof theMainte-
nance Schedulessection of this manual.
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Engine Oil Filter
Refer to Recommended Fluids, Lubricants and Genuine
Parts for the correct part number. The engine oil filter
should be changed ateveryengine oil change.
Engine Oil And Filter — Change
WARNING!
Hot oil can cause personal injury.
Operate the engine until the coolant temperature reaches
140°F (60°C). Shut the engine off. Remove the oil drain
plug.
Use a container that can hold at least 12 quarts (11.3
Liters) to hold the used oil.Always check the condition of the used oil. This can give
you an indication of some engine problems that might
exist.
•Thin, black oil indicates fuel dilution.
•Milky discoloration indicates coolant dilution.
Clean the area around the oil filter base. Remove the filter
from the underside of the vehicle using a cap style oil
filter wrench.
Clean the gasket surface of the filter mount. The filter
gasket can stick on the filter mount. Make sure it is
removed.
Change the engine oil filter with every engine oil change.
Only a high quality MOPAR filter should be used to
assure most efficient service.
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of the exhaust system abnormally contacts the under-
body hardware, the isolator and/or hanger should be
replaced.
Cooling System
Cooling System Maintenance
At the intervals shown in the Maintenance Schedules
Section of the manual, the system should be drained,
flushed and filled.
Inspection
Check engine coolant (antifreeze) protection every 12
months (before the onset of freezing weather, where
applicable). If coolant is dirty or rusty in appearance, the
system should be drained, flushed and refilled with fresh
coolant as specified.
Inspect the entire cooling system for leaks. Check the face
of the radiator for any accumulation of bugs, leaves, or
other foreign matter. If dirty, clean the radiator core witha garden hose. With the engine OFF, gently spray water
from the back of the radiator core. Check coolant bottle
tube for condition and tightness of connections at coolant
bottle and radiator.
Extremely cold ambient temperature may require the
addition of a “winter front” for effective operation of the
cab heating/cooling system. Make certain that a percent-
age of the radiator is exposed for adequate air flow
through the charge air cooler and automatic transmission
oil cooler. The percentage of opening must be increased
with the increasing ambient air temperature and/or
engine load. If the cooling fan can be heard cycling
frequently, increase the size of the opening in the winter
front.
Coolant bottle level check
The coolant reserve system provides a quick visual
method of determining that the coolant level is adequate.
With the engine idling, and warmed to the normal
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operating temperature, the level of the coolant on the
coolant bottle should be between the fluid level marks.
Check the coolant level whenever the hood is raised.
The radiator normally remains completely full, so there is
no longer a need to remove the coolant pressure cap
except for checking coolant freeze point or replacement
with new antifreeze coolant.
WARNING!
Never add coolant to the radiator when the engine is
overheated. Do not loosen or remove pressure cap to
cool overheated engine! The coolant is under pres-
sure and severe scalding could result.
Drain, Flush And Refill
At intervals shown on the Maintenance Schedules, the
system should be drained, flushed and refilled. Refer to
your dealer or consult a service manual for proper
procedures.
Adding Coolant
When adding coolant, or refilling the system, a minimum
solution of 50% recommended HOAT ethylene glycol
engine coolant (antifreeze) and distilled water should be
used. Use higher concentrations (not to exceed 70%) if
temperatures below34°F (37°C) are anticipated.
Use only high purity water such as distilled or deionized
water when mixing the water/engine coolant solution.
The use of lower quality water will reduce the amount of
corrosion protection in the engine cooling system.
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NOTE:It is the owner’s responsibility to maintain the
proper level of protection against freezing according to
the temperatures occurring in the area where the vehicle
is operated.
NOTE:Mixing coolant types will decrease the life of the
engine coolant and will require more frequent coolant
changes.
When additional coolant is needed to maintain the
proper level, add the recommended concentration of
antifreeze and water to the overflow bottle. Do not
overfill.
NOTE:Failure to follow the antifreeze concentration
and replacement recommendations, or failure to use
antifreeze formulated to prevent corrosion of all cooling
system metals, may result in radiator plugging, overheat-
ing, or cooling system leaks such as in core hole plugs.WARNING!
Never add coolant to the radiator when the engine is
overheated. Do not loosen or remove pressure cap to
cool an overheated engine. The coolant is under
pressure and severe scalding could result.
Recommended Engine Coolant
Refer to Recommended Fluids, Lubricants and Genuine
Parts for the correct Fluid type.
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