2020 Ram 3500 coolant temperature

STARTING AND OPERATING227
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, barometric
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 emissions 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
especially 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
City Traffic Maximum GCWR -Three
Highway Speeds Maximum GCWR -Four
Uphill Grade Maximum GCWR HotFive
5

20_DJD2_OM_EN_USC_t.book Page 227

228STARTING 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
S
PEED
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
(antifreeze) (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
(antifreeze) 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
conditions, take the following actions:
City Driving — When stopped, shift the trans -
mission into NEUTRAL and increase engine
idle speed.
Highway Driving — Reduce your speed.
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:
Idle 700 to 800 RPM 10 psi (69 kPa)
Full speed and load 30 psi (207 kPa)

20_DJD2_OM_EN_USC_t.book Page 228

230STARTING AND OPERATING
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
acceleration 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
recommended viscosity and quality grades,
refer to “Fluids And Lubricants” in “Technical
Specifications”.
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.
CAUTION!
Never use Non-Detergent Oil or Straight
Mineral Oil in the engine or damage may
result.

20_DJD2_OM_EN_USC_t.book Page 230

STARTING AND OPERATING233
(Continued)
NOTE:
For optimum braking power it is recommended
to use the exhaust brake while in TOW/HAUL
mode.
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 stopped or moving less than 5 mph
(8 km/h), the "Exhaust Brake Indicator" must be
on, and the coolant temperature must be below
180°F (82°C) and ambient temperature below
60°F (16°C). Automatic “Smart” Exhaust Brake
Automatic “Smart” Exhaust Brake technology
delivers smoother, less aggressive exhaust
braking characteristics during downhill
descents. Although it can apply full exhaust
braking force if needed, Automatic “Smart”
Exhaust Brake may not apply obvious braking if
the vehicle speed is not increasing. Automatic
“Smart” Exhaust Brake is intended to maintain
vehicle speed, while Full Exhaust Brake is
intended to reduce vehicle speed.
Automatic “Smart” Exhaust Brake can be
enabled by pushing the exhaust brake button
(on the center stack) again anytime after the
normal Full Exhaust Brake has been turned on.
The “Exhaust Brake Indicator” in the instrument
cluster display will change from Yellow to Green
when Automatic “Smart” Exhaust Brake is
enabled. Pushing the exhaust brake button
again will toggle the exhaust brake mode to off.
AUTOMATIC TRANSMISSION 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
possibly resulting in personal injury or death.
CAUTION!
Use of aftermarket exhaust brakes is not
recommended and could lead to engine
damage
WARNING!
Never use the PARK position as a substi
-
tute for the parking brake. Always apply the
parking brake fully when exiting the vehicle
to guard against vehicle movement and
possible injury or damage.
Your vehicle could move and injure you and
others if it is not in PARK. Check by trying to
move the transmission gear selector out of
PARK with the brake pedal released. Make
sure the transmission is in PARK before
exiting the vehicle.
The transmission may not engage PARK if
the vehicle is moving. Always bring the
vehicle to a complete stop before shifting to
PARK, and verify that the transmission gear
position indicator solidly indicates PARK (P)
without blinking. Ensure that the vehicle is
completely stopped, and the PARK position
is properly indicated, before exiting the
vehicle.
5

20_DJD2_OM_EN_USC_t.book Page 233

244STARTING AND OPERATING
available gears. Tapping the ERS (-) switch will
activate ERS mode, display the current gear in
the instrument cluster, and set that gear as the
top available gear. Once in ERS mode, tapping
the ERS (-) or (+) switch will change the top
available gear.

Electronic Range Select

To exit ERS mode, simply push and hold the ERS
(+) switch until the gear limit display disappears
from the instrument cluster. NOTE:
To select the proper gear position for maximum
deceleration (engine braking), simply push and
hold the ERS (-) switch. The transmission will
shift to the range from which the vehicle can
best be slowed down.
Overdrive Operation
The automatic transmission includes an
electronically controlled Overdrive (fifth and
sixth gears). The transmission will automatically
shift into Overdrive if the following conditions
are present:
The gear selector is in the DRIVE position.
The transmission fluid has reached an
adequate temperature.
The engine coolant has reached an adequate
temperature.
The vehicle speed is sufficiently high.
The driver is not heavily pressing the acceler
-
ator.
1 — GEAR + Switch
2 — GEAR – Switch
WARNING!
Do not downshift for additional engine
braking on a slippery surface. The drive
wheels could lose their grip and the vehicle
could skid, causing a collision or personal
injury.
Transmis -
sion Gear
Limit
Display 1 2 3 4 5 6 D
Actual
Gear(s)
Allowed
1 1-2 1-3 1-4 1-5 1-6 1-6
CAUTION!
When using ERS for engine braking while
descending steep grades, be careful not to
overspeed the engine. Apply the brakes as
needed to prevent engine overspeed.

20_DJD2_OM_EN_USC_t.book Page 244

380IN CASE OF EMERGENCY
FREEING A STUCK VEHICLE
If your vehicle becomes stuck in mud, sand, or
snow, it can often be moved using a rocking
motion. Turn the steering wheel right and left to
clear the area around the front wheels. Then
shift back and forth between DRIVE (D) and
REVERSE (R), while gently pressing the
accelerator. Use the least amount of
accelerator pedal pressure that will maintain
the rocking motion, without spinning the wheels
or racing the engine.
NOTE:
For trucks equipped with an 8–speed trans -
mission, shifts between DRIVE and REVERSE
can only be achieved at wheel speeds of
5 mph (8 km/h) or less. Whenever the trans -
mission remains in NEUTRAL (N) for more
than two seconds, you must press the brake
pedal to engage DRIVE or REVERSE.
Push the “ESC OFF” switch, to place the Elec -
tronic Stability Control (ESC) system in
“Partial Off” mode, before rocking the
vehicle. Refer to “Electronic Brake Control
System” in “Safety” for further information.
Once the vehicle has been freed, push the
“ESC OFF” switch again to restore “ESC On”
mode.WARNING!
You or others can be badly burned by hot
engine coolant (antifreeze) or steam from
your radiator. If you see or hear steam coming
from under the hood, do not open the hood
until the radiator has had time to cool. Never
try to open a cooling system pressure cap
when the radiator or coolant bottle is hot.
CAUTION!
Driving with a hot cooling system could
damage your vehicle. If the temperature
gauge reads HOT (H), pull over and stop the
vehicle. Idle the vehicle with the air
conditioner turned off until the pointer drops
back into the normal range. If the pointer
remains on HOT (H), and you hear continuous
chimes, turn the engine off immediately and
call for service.
WARNING!
Fast spinning tires can be dangerous. Forces
generated by excessive wheel speeds may
cause damage, or even failure, of the axle
and tires. A tire could explode and injure
someone. Do not spin your vehicle's wheels
faster than 30 mph (48 km/h) or for longer
than 30 seconds continuously without
stopping when you are stuck and do not let
anyone near a spinning wheel, no matter
what the speed.

20_DJD2_OM_EN_USC_t.book Page 380

385
SERVICING AND MAINTENANCE
SCHEDULED SERVICING — GAS ENGINE
Your vehicle is equipped with an automatic oil
change indicator system. The oil change
indicator system will remind you that it is time to
take your vehicle in for scheduled maintenance.

Based on engine operation conditions, the oil
change indicator message will illuminate. This
means that service is required for your vehicle.
Operating conditions such as frequent
short-trips, trailer tow, extremely hot or cold
ambient temperatures, and E85 fuel usage will
influence when the “Oil Change Required”
message is displayed. Severe Operating
Conditions can cause the change oil message to
illuminate as early as 3,500 miles (5,600 km)
since last reset. Have your vehicle serviced as
soon as possible, within the next 500 miles
(805 km).

An authorized dealer will reset the oil change
indicator message after completing the
scheduled oil change.If a scheduled oil change is performed by
someone other than an authorized dealer, the
message can be reset by referring to the steps
described under “Instrument Cluster Display” in
“Getting To Know Your Instrument Panel”.
NOTE:
Under no circumstances should oil change
intervals exceed 8,000 miles (13,000 km),
12 months or 350 hours of engine run time,
whichever comes first. The 350 hours of engine
run or idle time is generally only a concern for
fleet customers.
Severe Duty All Models
NOTE:
Change Engine Oil at 4,000 miles (6,500 km) or
350 hours of engine run time if the vehicle is
operated in a dusty and off road environment or
is operated predominantly at idle, or only very
low engine RPM. This type of vehicle use is
considered Severe Duty.
Once A Month Or Before A Long Trip:Check engine oil level
Check windshield washer fluid level
Check tire pressure and look for unusual
wear or damage. Rotate tires at the first sign
of irregular wear, even if it occurs before the
oil indicator system turns on.
Check the fluid levels of the coolant reservoir,
brake master cylinder, power steering and
automatic transmission (six-speed only) and
fill as needed
Check function of all interior and exterior
lights7

20_DJD2_OM_EN_USC_t.book Page 385

SERVICING AND MAINTENANCE417
Under normal operating conditions, the
catalytic converter will not require
maintenance. However, it is important to keep
the engine properly tuned to ensure proper
catalyst operation and prevent possible catalyst
damage. NOTE:
Intentional tampering with emissions control
systems can result in civil penalties being
assessed against you.
In unusual situations involving grossly
malfunctioning engine operation, a scorching
odor may suggest severe and abnormal catalyst
overheating. If this occurs, stop the vehicle, turn
off the engine and allow it to cool. Service,
including a tune-up to manufacturer's
specifications, should be obtained immediately.
To minimize the possibility of catalytic converter
damage:
Do not interrupt the ignition when the trans
-
mission is in gear and the vehicle is in
motion.
Do not try to start the vehicle by pushing or
towing the vehicle.
Do not idle the engine with any ignition
components disconnected or removed, such
as when diagnostic testing, or for prolonged
periods during very rough idle or malfunc -
tioning operating conditions.
COOLING SYSTEM CAUTION!
The catalytic converter requires the use of
unleaded fuel only. Leaded gasoline will
destroy the effectiveness of the catalyst as
an emissions control device and may seri -
ously reduce engine performance and
cause serious damage to the engine.
Damage to the catalytic converter can
result if your vehicle is not kept in proper
operating condition. In the event of engine
malfunction, particularly involving engine
misfire or other apparent loss of perfor -
mance, have your vehicle serviced
promptly. Continued operation of your
vehicle with a severe malfunction could
cause the converter to overheat, resulting
in possible damage to the converter and
vehicle.
WARNING!
You or others can be badly burned by hot
engine coolant (antifreeze) or steam from
your radiator. If you see or hear steam
coming from under the hood, do not open
the hood until the radiator has had time to
cool. Never open a cooling system pressure
cap when the radiator or coolant bottle is
hot.
Keep hands, tools, clothing, and jewelry
away from the radiator cooling fan when
the hood is raised. The fan starts automati -
cally and may start at any time, whether the
engine is running or not.
When working near the radiator cooling fan,
disconnect the fan motor lead or turn the
ignition to the OFF mode. The fan is
temperature controlled and can start at any
time the ignition is in the ON mode.7

20_DJD2_OM_EN_USC_t.book Page 417