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If temperatures are below 32°F (0°C), operate the engine
at moderate speeds for 5 minutes before full loads are
applied.
Engine Idling — In Cold Weather
Avoid prolonged idling in ambient temperatures below
0°F. Long periods of idling may be harmful to your
engine because combustion chamber temperatures can
drop so low that the fuel may not burn completely.
Incomplete combustion allows carbon and varnish to
form on piston rings and injector nozzles. Also, the
unburned fuel can enter the crankcase, diluting the oil
and causing rapid wear to the engine.
NOTE:An optional driver-controlled high idle speed is
available on automatic transmission equipped vehicles
with speed control. This feature allows the driver to
select an elevated idle speed between 1100 and 1500
rpms. Your dealer can enable this feature.NOTE:
•If ambient temperatures are low and the coolant
temperature is below 200°F (93°C), the engine idle
speed will slowly increase to 1000 RPM after 2 minutes
of idle, if the following conditions are met:
•foot is off brake pedal and throttle pedal
•automatic transmission is in Park (P)
•vehicle speed is zero
•Applying the throttle will cancel fast idle
•If the engine is equipped with an aftermarket exhaust
brake (manual transmissions only), operating the ex-
haust brake at idle will greatly improve warm up rate
and will help keep the engine close to operating
temperature during extended idle.
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Stopping The Engine
Idle the engine a few minutes before routine shutdown.
After full load operation, idle the engine 3 to 5 minutes
before shutting it down. This idle period will allow the
lubricating oil and coolant to carry excess heat away from
the combustion chamber, bearings, internal components,
and turbocharger. This is especially important for turbo-
charged, charge air cooled engines, like your Turbo Ram.
Driving
ConditionLoadTurbo-
charger
TemperatureIdle Time
(min.) Be-
fore Engine
Shutdown
Stop and
GoEmpty Cool Less than
One
Stop and
GoMedium One
Highway
SpeedsMedium Warm Two
City Traffic Maximum
GCWRThree
Highway
SpeedsMaximum
GCWRFour
Uphill
GradeMaximum
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.
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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.
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.
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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.
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
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Checking the vehicle while it’s on level ground will also
improve the accuracy of the oil level readings. Add oil
only when the level on the dipstick is below the “ADD”
mark. The total capacity from the low mark to the high
mark is 2 quarts (1.9 liters).
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).
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•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.
NOTE:Most vehicles are operated under the conditions
listed for ScheduleB.
Engine Oil Selection
1. Engine Oil Quality
Use only oils conforming to API Ser-
vice CI-4. A sulfated ash limit is speci-
fied for lubrication oil used in Cum-
mins engines. Oils with a high ash
content may produce deposits on
valves that can progress to guttering
and valve burning. A maximum sul-
fated ash content of 1.85 mass % is recommended for all
oil used in the engine.
2. Engine Oil Viscosity (SAE Grade)
The proper SAE viscosity of engine oil for the expected
ambient temperature range should be selected, as indi-
cated in the following chart:
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NOTE:The same oil change interval is to be followed
for synthetic oil as for petroleum based oil. Also, syn-
thetic oil must meet the same performance specifications
as petroleum oil.Engine Oil Filter
Refer to 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.
382 MAINTAINING YOUR VEHICLE
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amount of a high quality lubricant such as MoparLock
Cylinder Lubricant directly into the lock cylinder.
Windshield Wiper Blades
The rubber edges of the wiper blades and the windshield
should be cleaned periodically with a sponge or soft cloth
and a mild nonabrasive cleaner. This will remove accu-
mulations of salt or road film.
Operation of the wipers on dry glass for long periods
may cause deterioration of the wiper blades. Always use
washer fluid when using the wipers to remove salt or dirt
from a dry windshield.
Avoid using the wiper blades to remove frost or ice from
the windshield. Keep the blade rubber out of contact with
petroleum products such as engine oil, gasoline, etc.
Windshield Washers
The fluid reservoir is located under the hood and should
be checked for fluid level at regular intervals. Fill the
reservoir with windshield washer solvent only (not ra-
diator antifreeze).
When refilling the washer fluid reservoir, take some
washer fluid and apply it to a cloth or towel and wipe
clean the wiper blades, this will help blade performance.
To prevent freeze-up of your windshield washer system
in cold weather, select a solution or mixture that meets or
exceeds the temperature range of your climate. This
rating information can be found on most washer fluid
containers.
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