engine DODGE RAM 3500 DIESEL 2008 3.G Workshop Manual

²Climatized Ultra Low Sulfur Diesel Fuel is a blend of
Number 2 Ultra Low Sulfur and Number 1 Ultra Low
Sulfur Diesel Fuels which reduces the temperature at
which wax crystals form in fuel.
NOTE:The engine requires the use ofªUltra Low
Sulfur Diesel Fuelº. Use of incorrect fuel could result in
engine and exhaust system damage. Refer to Fuel Re-
quirements in this section for further details on fuel
recommendations.
Engine Block Heater
The engine block heater warms engine coolant and
permits quicker starts in cold weather. Connect the heater
cord to a ground±fault interrupter protected 110±115 volt
AC electrical outlet with a grounded, three-wire exten-
sion cord.
The engine block heater cord is routed under the hood to
the right side and can be located just behind the grille
near the headlamp.NOTE:The engine block heater cord is a factory in-
stalled option. If your vehicle is not equipped, heater
cords are available from your authorized Mopartdealer.
The block heater must be plugged in at least one hour to
have an adequate warming effect on the coolant.
WARNING!
Remember to disconnect the cord before driving.
Damage to the 110±115 volt electrical cord could
cause electrocution.
NOTE:The block heater will require 110 Volts AC and
6.5 Amps to activate the heater element.
276 STARTING AND OPERATING

Block Heater Usage
A.Temperatures below 0ÉF (-18ÉC)
²Block Heater Required for 15W-40
²Block Heater Recommended for 5W-40
B.Temperatures below - 20ÉF (-29ÉC)
²Block Heater Required for 5W-40
Winter Front Usage
If a winter front or cold weather cover is to be used, a
percentage of the total grille opening area must be left
uncovered to provide sufficient air flow to the charge air
cooler and automatic transmission oil cooler. The per-
centage 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. A suitable cold
weather cover is available from your Mopartdealer.
Battery Blanket Usage
A battery loses 60% of its cranking power as the battery
temperature decreases to 0ÉF (-18É). For the same de-
crease in temperature, the engine requires twice as much
power to crank at the same RPM. The use of 120 VAC
powered battery blankets will greatly increase starting
capability at low temperatures. Suitable battery blankets
are available from your authorized Mopartdealer.
Arctic Operation
Where there are no provisions to keep the engine warm
when it is operating in ambient temperatures consistently
below (-10ÉF/-23ÉC), use 5W-40syntheticengine oil and
fuel that meets the requirements in Section 7, ªMainte-
nance Procedures,º Engine Oil Selection.
Engine Warm-Up
Avoid full throttle operation when the engine is cold.
When starting a cold engine, bring the engine up to
operating speed slowly to allow the oil pressure to
stabilize as the engine warms up.
STARTING AND OPERATING 277
5

NOTE:High-speed, no-load running of a cold engine
can result in excessive white smoke and poor engine
performance. No-load engine speeds should be kept
under 1,200 rpm during the warm-up period, especially
in cold ambient temperature conditions.
If temperatures are below 32ÉF (0ÉC), operate the engine
at moderate speeds for 5 minutes before full loads are
applied.
Engine Idling
Avoid prolonged idling, 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.
CAUTION!
Extended periods of idle time may not allow the
vehicle's exhaust aftertreatment system to properly
regenerate. This can lead to the illumination of the
Malfunction Indicator Light (MIL) or an Electronic
Vehicle Information Center (EVIC) warning message.
Operating the engine for extended periods with the
MIL illuminated or an EVIC warning message dis-
played can cause extensive engine and exhaust sys-
tem damage.
NOTE:Your vehicle is equipped with a turbo speed
limiter, this feature limits the engine speed to 1200 rpm
when engine coolant temperatures are below 70ÉF (21ÉC).
This feature is designed to protect the turbo charger from
damage and will only operate in PARK or NEUTRAL.
278 STARTING AND OPERATING

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.
The optional driver-controlled high idle speed will help
increase cylinder temperatures and provide additional
cab heat, however, may still cause the exhaust aftertreat-
ment system to not properly regenerate. Extended peri-
ods of idle time should be avoided.
NOTE:
²If ambient temperatures are low and the coolant
temperature is below 200ÉF (93ÉC), the engine idle
speed will slowly increase to 1000 RPM after 2 minutes
of idle, if the following conditions are met:
²foot is off brake pedal and throttle pedal
²automatic transmission is in Park (P)
²vehicle speed is zero
²Applying the throttle will cancel fast idle
²If the engine is equipped with an exhaust brake,
operating the exhaust brake at idle will greatly im-
prove warm up rate and will help keep the engine
close to operating temperature during extended idle.
CAUTION!
Use of aftermarket exhaust brakes is not recom-
mended and could lead to engine damage
STARTING AND OPERATING 279
5

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.
NOTE:During engine shutdown on vehicles equipped
with manual transmissions, it is normal for the diesel
engine to resonate heavily for a moment during engine
shut off. When the engine is connected to a manual
transmission, this resonance causes loud gear rattle from
the transmission. This is commonly referred to as ªshut
down rattleº. The manufacturer recommends performing
engine shut down with the clutch pedal pushed to the
floor (clutch disengaged). When engine shut down is
performed in this manner the rattle is reduced (not
eliminated).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
280 STARTING AND OPERATING

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 (240ÉF/116ÉC)
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 (140ÉF/60ÉC) 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 Ð Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
²City Driving Ð
when stopped, put transmission in neutral and increase
engine idle speed.
²Highway Driving Ð
reduce your speed.
STARTING AND OPERATING 281
5

²Up Steep Hills Ð
select a lower transmission gear, but try and keep the
torque converter clutch engaged.
²Air Conditioning Ð
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.
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:
²engine misfiring or vibrating severely
²sudden loss of power
²unusual engine noises
²fuel, oil or coolant leaks
²sudden change, outside the normal operating range, in
the engine operating temperature
²excessive smoke
²oil pressure drop
282 STARTING AND OPERATING

DIESEL EXHAUST BRAKE (ENGINE BRAKING) ±
IF EQUIPPED
The exhaust brake feature will only function when the
driver turns the exhaust brake switch to the ON position.
Once the switch is in the ON position and the vehicle is
moving faster than 5 mph (8 km/h); the exhaust brake
will automatically operate when the driver removes
pressure from the accelerator pedal. Exhaust braking is
most effective when the engine RPM is higher. The
automatic transmission has been programmed to down-
shift more aggressively when the exhaust brake is en-
abled to increase brake performance.
Exhaust Brake Switch
STARTING AND OPERATING 283
5

WARNING!
Do not use the Exhaust Brake feature when driving
in icy or slippery conditions as the increased engine
braking can cause the rear wheels to slide and the
vehicle to swing around with the possible loss of
vehicle control, which may cause an accident possi-
bly resulting in personal injury or death.
NOTE:For optimum braking power it is recommended
to use the Exhaust Brake while in Tow/Haul Mode.
The purpose of the exhaust brake (engine braking) fea-
ture is to supply negative (braking) torque to the engine.
Typically, the engine braking is used for, but not limited
to, vehicle towing applications where vehicle braking can
be achieved by the internal engine power, thereby spar-
ing the mechanical brakes of the vehicle.Benefits of the exhaust brake are:²vehicle driving control
²reduced brake fade
²longer brake life
²faster cab warm-up.
The exhaust brake feature can also be used to reduce the
engine warm up time. To use the exhaust brake as a
warm-up device, the vehicle must be moving less than 5
mph (8 km/h), the exhaust brake switch must be in the
ON position, and the coolant temperature must below
180ÉF (82ÉC) and ambient temperature below 60ÉF (16ÉC).
284 STARTING AND OPERATING

TRANSMISSION SHIFTING
Automatic Transmission with Overdrive
(68RFE) Ð If Equipped
The gear selector lever 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 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.PARK
This gear position supplements the parking brake by
locking the transmission. The engine can be started in
this range. Never use PARK while the vehicle is in
motion. Apply the parking brake when leaving the
vehicle in this range. Always apply parking brake first,
then place the selector in PARK position. On 4-wheel
drive vehicles be sure that the transfer case is in a drive
position!
WARNING!
Never use PARK position on an automatic transmis-
sion as a substitute for the parking brake. Always
apply parking brake fully when parked to guard
against vehicle movement and possible injury or
damage.
STARTING AND OPERATING 285
5