Ram 2500 2020 Owner's Manual

STARTING AND OPERATING219
5. Check that the oil pressure warning light
has turned off.
6. Release the parking brake.
Starting Procedure — Engine Manifold Air
Temperature 0°F To 66°F (–18°C to 19°C)
NOTE:
The temperature displayed in the instrument
cluster does not necessarily reflect the engine
manifold air temperature. Refer to “Instrument
Cluster Display” in “Getting To Know Your
Instrument Panel” for further information.
When engine temperatures fall below 66°F
(19°C) the “Wait To Start Light” will remain on
indicating the intake air heater system is active.
Follow the steps in the “Normal Starting” proce -
dure except:
1. The “Wait To Start” telltale will remain on
for a period of time that varies depending
on the engine temperature.

2. While the “Wait To Start” telltale is on, the instrument cluster will additionally display a
gauge or bar whose initial length represents
the full “Wait To Start” time period. Its
length will decrease until it disappears
when the “Wait To Start” time has elapsed.
3. After the “Wait To Start” telltale goes off, place the ignition switch in the START posi -
tion. Do not press the accelerator during
starting. 4. After engine start-up, check that the oil
pressure warning light has turned off.
5. Release the parking brake and drive.
NOTE:
Engine idle speed will automatically increase
to 1,000 RPM and engage the Variable
Geometry Turbocharger at low coolant
temperatures to improve engine warm-up.
Automatic equipped vehicles with optional
Keyless Enter-N-Go – If the start button is
pushed once while in park with the ignition
off and driver’s foot on the brake pedal, the
vehicle will automatically crank and start
after the Wait to Start time has elapsed. If it
is desired to abort the start process before it
CAUTION!
Do not crank engine for more than 25 seconds
at a time or starter motor damage may result.
Turn the ignition switch to the OFF position and
wait at least two minutes for the starter to cool
before repeating start procedure.
CAUTION!
If the “Water in Fuel Indicator Light” remains
on, DO NOT START the engine before you
drain the water from the fuel filters to avoid
engine damage. Refer to “Draining Fuel/
Water Separator Filter” in “Servicing And
Maintenance” for further information.
CAUTION!
Do not crank engine for more than 25 seconds
at a time or starter motor damage may result.
Turn the ignition switch to the OFF position and
wait at least two minutes for the starter to cool
before repeating start procedure.
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220STARTING AND OPERATING
completes, the driver’s foot should be fully
removed from the brake pedal prior to
pushing the start button again in order for the
ignition to move directly to off.
If the engine stalls, or if the ignition switch is
left ON for more than two minutes after the
“Wait To Start” telltale goes out, reset the
intake air heater by turning the ignition
switch to the OFF position for at least five
seconds and then back ON. Repeat steps
1 through 5 of “Starting Procedure – Engine
Manifold Air Temperature Below 66°F
(19°C).”
Starting Procedure — Engine Manifold Air
Temperature Below 0°F (-18°C)
In extremely cold weather below 0°F (-18°C) it
may be beneficial to cycle the intake air heater
twice before attempting to start the engine. This
can be accomplished by turning the ignition OFF
for at least 5 seconds and then back ON after
the “Wait To Start” telltale has turned off, but
before the engine is started. However, exces -
sive cycling of the intake air heater will result in
damage to the heater elements or reduced
battery voltage. NOTE:
If multiple pre-heat cycles are used before
starting, additional engine run time may be
required to maintain battery state of charge at a
satisfactory level.

1. If the engine stalls after the initial start, the
ignition must be turned to the OFF position
for at least five seconds and then to the ON
position to recycle the intake air heater.

NOTE:
Excessive white smoke and poor engine perfor -
mance will result if intake air heater are not
recycled.
2. Heat generated by the intake air heater dissipates rapidly in a cold engine. If more
than two minutes pass between the time
the “Wait To Start” telltale turns off and the
engine is started, recycle the intake air
heater by turning the ignition switch to the
OFF position for at least five seconds and
then back ON.
3. If the vehicle is driven and vehicle speed exceeds 19 mph (31 km/h) before the
intake air heater post-heat (after start) cycle
is complete, the intake air heater will shut
off. 4. If the engine is cranked for more than
10 seconds, the post-heat cycle will turn off.
NOTE:
Engine idle speed will automatically increase
to 1,000 RPM and engage the Variable
Geometry Turbocharger at low coolant
temperatures to improve engine warm-up.
When a diesel engine is allowed to run out of
fuel or the fuel gels at low temperatures, air
is pulled into the fuel system. If your engine
has run out of fuel, refer to “Dealer Service/
Priming If The Engine Has Run Out Of Fuel” in
“Servicing And Maintenance” for further
information.
If the engine stalls, or if the ignition switch is
left ON for more than two minutes after the
“Wait To Start” telltale goes out, reset the
intake air heater by turning the ignition
switch to the OFF position for at least 5
seconds and then back ON. Repeat steps
1 through 5 of “Starting Procedure – Engine
Manifold Air Temperature Below 66°F
(19°C).”

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STARTING AND OPERATING221
(Continued)
Starting Fluids
The engine is equipped with an automatic elec -
tric air preheating system. If the instructions in
this manual are followed, the engine should
start in all conditions.
NORMAL OPERATION — DIESEL ENGINE
Observe the following when the engine is oper -
ating.
All message center lights are off.
Malfunction Indicator Light (MIL) is off.
Engine oil pressure is above 10 psi (69 kPa)
at idle.
Voltmeter operation:
The voltmeter may show a gauge fluctuation at
various engine temperatures. This cycling oper -
ation is caused by the post-heat cycle of the
intake manifold heater system. The number of
cycles and the length of the cycling operation is
controlled by the engine control module.
Post-heat operation can run for several
minutes, and then the electrical system and
voltmeter needle will stabilize.
The cycling action will cause temporary
dimming of the headlamps, interior lamps, and
also a noticeable reduction in blower motor
speed.
Cold Weather Precautions
Operation in ambient temperature below 32°F
(0°C) may require special considerations. The
following charts suggest these options:
WARNING!
Starting fluids or flammable liquids must
never be used in the Cummins diesel engine
(see Warning label). Never pour diesel fuel,
flammable liquid, starting fluids (ether) into
the air cleaner canister, air intake piping, or
turbocharger inlet in an attempt to start the
vehicle. This could result in a flash fire and
explosion causing serious personal injury and
engine damage.
WARNING!
Do not leave children or animals inside
parked vehicles in hot weather. Interior heat
build up may cause serious injury or death.
When leaving the vehicle, always make
sure the keyless ignition node is in the
“OFF” mode, remove the key fob from the
vehicle and lock the vehicle.
Never leave children alone in a vehicle, or
with access to an unlocked vehicle.
Allowing children to be in a vehicle unat -
tended is dangerous for a number of
reasons. A child or others could be seriously
or fatally injured. Children should be
warned not to touch the parking brake,
brake pedal or the gear selector.
Do not leave the key fob in or near the
vehicle, or in a location accessible to chil -
dren, and do not leave the ignition of a
vehicle equipped with Keyless Enter-N-Go
in the ACC or ON/RUN mode. A child could
operate power windows, other controls, or
move the vehicle.
WARNING! (Continued)
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222STARTING AND OPERATING
Fuel Operating Range
NOTE:
Use “Ultra Low Sulfur Diesel Fuels” ONLY.
Fuel Operating Range Chart
*No. 1 Ultra Low Sulfur Diesel Fuel should only be used where extended arctic conditions (0°F/-18°C) exist”.

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STARTING AND OPERATING223
NOTE:
Use of Climatized Ultra Low Sulfur Diesel Fuel
or Number 1 Ultra Low Sulfur Diesel Fuel
results in a noticeable decrease in fuel
economy.
Climatized 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.
The fuel grade should be clearly marked on
the pump at the fuel station.
The engine requires the use of “Ultra Low
Sulfur Diesel Fuel”. Use of incorrect fuel
could result in engine and exhaust system
damage. Refer to “Fuel Requirements” in
“Technical Specifications” for further infor -
mation.
If climatized or diesel Number 1 ULSD fuel is
not available, and you are operating below
(20°F/-6°C), in sustained arctic conditions,
Mopar Premium Diesel Fuel Treatment (or
equivalent) is recommended to avoid gelling
(see Fuel Operating Range Chart).

Under some circumstances increased
engine noise may be audible in the seconds
following a cold start. This is most likely to
occur when using fuel that isn't blended for
the ambient temperature present. This may
occur on an unseasonably cold day or when
a truck is fueled in a warmer climate and
driven to a colder climate. The noise can
typically be prevented by using Mopar
Premium Diesel Fuel Treatment as recom-
mended (see Fuel Operating Range Chart).

Engine Oil Usage
Refer to “Dealer Service” in “Servicing And
Maintenance” for the correct engine oil
viscosity.
Winter Front Cover Usage
A Winter front or cold weather cover is to be
used in ambient temperatures below 32°F
(0°C), especially during extended idle condi -
tions. This cover is equipped with four flaps for
managing total grille opening in varying ambient
temperatures. If a Winter front or cold weather
cover is to be used the flaps should be left in the
full open position to allow air flow to the charge
air cooler and automatic transmission oil
cooler. When ambient temperatures drop below
0°F (-17°C) the four flaps need to be closed. A suitable cold weather cover is available from
your Mopar dealer.
Battery Blanket Usage
A battery loses 60% of its cranking power as the
battery temperature decreases to 0°F (-18°C).
For the same decrease 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
Mopar dealer.
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.
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 1,000 RPM during the
warm-up period, especially in cold ambient
temperature conditions.
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224STARTING AND OPERATING
Your vehicle is equipped with an engine warm
up protection feature that may limit engine
performance after cold starting at low ambient
temperatures. The length of time engine speed
is limited is dependent upon engine coolant
temperature. Engine speed may be briefly
limited to 1000 RPM after starting with coolant
temperature below freezing conditions, and
may be limited to 1000 RPM for up to approxi -
mately 2 minutes under more severe cold
conditions.
NOTE:
If ambient temperatures are low and the
coolant temperature is below 180°F (82°C),
the engine idle speed will slowly increase to
1,000 RPM after two minutes of idle, if the
following conditions are met:
Foot is off brake pedal and throttle pedal.
Automatic transmission is in PARK.
Vehicle speed is 0 mph (0 km/h).
Applying the throttle will cancel fast idle.
Operating the exhaust brake at idle will
greatly improve warm up rate and will help
keep the engine close to operating tempera -
ture during extended idle.
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, engine valves,
and injector nozzles. Also, the unburned fuel
can enter the crankcase, diluting the oil and
causing rapid wear to the engine.
If the engine is allowed to idle or the truck is
driven on low engine speed drive cycles for
more than 2 hours, the system will automati -
cally enter an emissions operating mode that
will increase the engine idle speed to 900 RPM.
While in this mode, which is designed to help
maintain the diesel particulate filter, the engine
idle speed will return to normal when the brake
pedal is applied. A small change in engine tone
or a slight change in engine performance while
accelerating may also be noticeable at speeds
below 20 mph (32 kmh). This operating mode
may last for up to an hour of idle time, or around
20 minutes of driving time.
Your truck may have been ordered with an
optional voltage monitoring idle up feature. If a
load is placed on the electrical system while the truck is in park, this feature will attempt to
maintain normal system voltage by automati
-
cally increasing engine idle speed. You may
notice several consecutive increases in idle
speed, up to a maximum of 1,450 RPM, as the
system will attempt to utilize the smallest
increase in idle speed necessary to maintain
normal system voltage. The idle speed will
return to normal when either the electrical load
is removed, or when the brake pedal is applied.
NOTE:
For instrument cluster display messages
related to the vehicle's exhaust system, refer to
“Instrument Cluster Display” in “Getting To
Know Your Instrument Panel” for further infor -
mation.
Idle-Up Feature
The driver-controlled high idle speed feature will
help increase cylinder temperatures and
provide additional cab heat, however, excessive
idling may still cause the exhaust aftertreat -
ment system to not properly regenerate.
Extended periods of idle time should be
avoided.
The Idle-Up feature uses the Speed Control
switches to increase engine idle speed and
quickly warm the vehicle's interior.

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STARTING AND OPERATING225

1. With the transmission in PARK, the parking
brake applied, and the engine running,
push the speed control switch to the ON
position, then push the SET switch.

2. The engine RPM will go up to 1,100 RPM. To increase the RPM, push and hold the
ACCEL/RESUME switch and the idle speed
will increase to approximately 1,500 RPM.
To decrease the RPM, push and hold the
DECEL switch and the idle speed will
decrease to approximately 1,100 RPM.
3. To cancel the Idle–Up feature, either push the CANCEL switch, push the ON/OFF
switch, or press the brake pedal.
Noise
Diesel engines can create noises that may
seem concerning. The nature of a diesel engine
is compression ignition where compressed air and fuel are mixed and ignited. Weather, baro
-
metric pressure, altitude, and temperature will
affect how fuel is ignited in the engine. Engines
will sound different from day to day or previous
model years. Clicking, ticking, or light knocking
is normal and will change from day to day, as
the engine breaks in, and can vary with changes
in ambient temperature. Clicking sound from
under the hood shortly after vehicle shutdown is
normal as actuators such as the EGR valve are
cycled. Fuel pump noise may increase during
low speed/light load conditions when ambient
temperature is above 100°F (38°C), and when
fuel tank level is below 10% which is a normal
condition of the fuel system and controls
strategy. Diesel equipped vehicles also have an
exhaust after-treatment system to reduce emis -
sions utilizing a DPF (refer to “Odor” in this
section for further information) and a Selective
Reduction Catalyst (SCR). The SCR reduces
Nitrogen Oxides (NOx) using the Diesel Exhaust Fluid (DEF) system. DEF is injected directly into
the SCR through a dosing module. This process
will create a clicking sound and at times, will
make noise even with the vehicle shut off. This
is normal as the DEF dosing module is purging
DEF. If at any time the check engine light is on,
please visit an authorized dealer.
Stopping The Engine
Idle the engine a few minutes before routine
shutdown. After full load operation, idle the
engine three to five 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 espe
-
cially important for turbocharged, charge
air-cooled engines. Refer to the following chart
for proper engine shutdown:
Driving Condition Load Turbocharger Temperature Idle Time (min.) Before Engine
Shutdown
Stop and Go EmptyCoolLess than One
Stop and Go Medium -One
Highway Speeds MediumWarmTwo
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226STARTING AND OPERATING
Idle Shutdown
This feature can be enabled so that the truck
will automatically shutdown when the truck has
been idling for a set period of time when the
engine is at operating temperature. Idle time
can be set in 5 minute increments between 5
and 60 minutes. See an authorized dealer to
enable this feature.
NOTE:
The idle shut down timer is disabled while the
PTO is active.
Programmable Maximum Vehicle Speed
This feature allows the owner to set a maximum
vehicle speed for the vehicle. The 2500 and
3500 Series maximum vehicle speed can be set
between 40 mph (64 km/h) and 87 mph
(140 km/h). The 4500/5500 Series maximum
vehicle speed can be set between 40 mph (64 km/h) and 85 mph (136 km/h). See an
authorized dealer to enable this feature.
NOTE:
DO NOT set the maximum vehicle speed to a
value greater than what the vehicle tires are
rated for.
Operating Precautions
Avoid Overheating The Engine
The temperature of the engine coolant (anti
-
freeze) (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 21 psi (145 kPa) coolant pressure cap.
Usually the engine coolant (antifreeze)
temperature indicated during operation will be
to the left of center in the normal range of the
gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low engine coolant (anti -
freeze) temperature below the normal range on
the gauge 140°F (60°C) can be harmful to the
engine. Low engine coolant (antifreeze)
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
To reduce potential for engine and transmission
overheating in high ambient temperature condi -
tions, take the following actions:
City Driving — When stopped, shift the trans -
mission into NEUTRAL and increase engine
idle speed.
Highway Driving — Reduce your speed.
City Traffic
Maximum GCWR -Three
Highway Speeds Maximum GCWR -Four
Uphill Grade Maximum GCWR HotFive
Driving Condition Load Turbocharger Temperature Idle Time (min.) Before Engine
Shutdown

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STARTING AND OPERATING227
Up Steep Hills — Select a lower transmission
gear.
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:
Do Not Operate The Engine With Failed Parts
All engine failures give some warning before the
parts fail. Be on the alert for changes in perfor -
mance, 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 oper -
ating range, in the engine operating tempera -
ture.
Excessive smoke.
Oil pressure drop.
ENGINE BLOCK HEATER — GAS ENGINE (IF
EQUIPPED)
The engine block heater warms the engine, and
permits quicker starts in cold weather. Connect
the cord to a standard 110-115 Volt AC elec -
trical outlet with a grounded, three-wire exten -
sion cord.
The engine block heater cord is routed through
the grille by the right front tow hook.
It includes a removable cap that is secured by a
tethered strap. It also has a c-clip that is used
for storage when not in use for the winter
months. During winter months, remove the
heater cord wiring assembly from itself on the
c-clip. The engine block heater must be plugged in at
least one hour to have an adequate warming
effect on the engine.
ENGINE BLOCK HEATER — DIESEL ENGINE
(IF EQUIPPED)
The engine block heater warms engine coolant
and permits quicker starts in cold weather.
Connect the heater cord to a ground-fault inter
-
rupter protected 110–115 Volt AC electrical
outlet with a grounded, three-wire extension
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
installed option. If your vehicle is not equipped,
heater cords are available from an authorized
Mopar dealer.
Idle 700 to 800 RPM 10 psi (69 kPa)
Full speed and load 30 psi (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.
WARNING!
Remember to disconnect the engine block
heater cord before driving. Damage to the
110-115 Volt electrical cord could cause
electrocution.
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228STARTING AND OPERATING
The block heater must be plugged in at least
one hour to have an adequate warming effect
on the coolant.
NOTE:
The block heater will require 110 Volts AC and
6.5 Amps to activate the heater element.
Block Heater Usage
For ambient temperatures below 0°F (-18°C),
engine block heater usage is recommended.
For ambient temperatures below –20°F
(-29°C), engine block heater usage is required.
ENGINE BREAK-IN RECOMMENDATIONS —
GAS ENGINE
A long break-in period is not required for the
engine and drivetrain (transmission and axle) in
your vehicle.
Drive moderately during the first 300 miles
(500 km). After the initial 60 miles (100 km), speeds up to 50 or 55 mph (80 or 90 km/h) are
desirable.
While cruising, brief full-throttle acceleration
within the limits of local traffic laws contributes
to a good break-in. Wide-open throttle accelera-
tion in low gear can be detrimental and should
be avoided.
The engine oil installed in the engine at the
factory is a high-quality energy conserving type
lubricant. Oil changes should be consistent with
anticipated climate conditions under which
vehicle operations will occur. For the recom
-
mended viscosity and quality grades, refer to
“Fluids And Lubricants” in “Technical Specifica-
tions”.
NOTE:
A new engine may consume some oil during its
first few thousand miles (kilometers) of opera -
tion. This should be considered a normal part of
the break-in and not interpreted as a problem.
Please check your oil level with the engine oil indicator often during the break in period. Add
oil as required.
ENGINE BREAK-IN RECOMMENDATIONS —
DIESEL ENGINE
The Cummins® Turbo Diesel engine does not
require a break-in period due to its construction.
Normal operation is allowed, providing the
following recommendations are followed:
Warm up the engine before placing it under
load.
Do not operate the engine at idle for
prolonged periods.
Use the appropriate transmission gear to
prevent engine lugging.
Observe vehicle oil pressure and tempera
-
ture indicators.
Check the coolant and oil levels frequently.
Vary throttle position at highway speeds
when carrying or towing significant weight.
WARNING!
Remember to disconnect the cord before
driving. Damage to the 110–115 Volt
electrical cord could cause electrocution.
CAUTION!
Never use Non-Detergent Oil or Straight
Mineral Oil in the engine or damage may
result.

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