2020 Ram 3500 Chassis Cab coolant temperature

STARTING AND OPERATING201
Diesel Particulate Filter (DPF) Manual
Regeneration - If Equipped
On equipped chassis cabs, a manual regenera -
tion can be enable through the instrument
cluster. The manual regeneration will allow the
DPF to complete a regeneration, lowering the
soot level without having to drive the vehicle.
The vehicle must be in park to access this
feature, and the fuel level must be over 12.5%
full. A message displaying the time left on the
regeneration will appear on the instrument
cluster, and the instrument cluster will display
the soot level. Refer to “Instrument Cluster
Display” in “Getting to Know Your Instrument
Panel” for further information.
ENGINE BLOCK HEATER — 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.
Gas Engine Only
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.
Diesel Engine Only
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.
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.
WARNING!
Remember to disconnect the engine block
heater cord before driving. Damage to the
110-115 Volt electrical cord could cause
electrocution.
WARNING!
Remember to disconnect the engine block
heater cord before driving. Damage to the
110-115 Volt electrical cord could cause
electrocution.5

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STARTING AND OPERATING203
DIESEL EXHAUST BRAKE (ENGINE
BRAKING)
The purpose of the exhaust brake (engine
braking) feature is to supply negative (braking)
torque from 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 sparing the mechanical brakes of the
vehicle.
Benefits of the exhaust brake are:
Vehicle driving control.
Reduced brake fade.
Longer brake life.
Faster cab warm-up.
The exhaust brake feature will only function
when the driver toggles it on by pushing the
exhaust brake button until the "Exhaust Brake
Indicator" is illuminated. Normal (Full Strength)
exhaust brake mode is indicated by a yellow
"Exhaust Brake Indicator".
Exhaust Brake Switch

Once the "Exhaust Brake Indicator” is illumi-
nated and the vehicle is moving faster than
5 mph (8 km/h); the exhaust brake will auto -
matically operate when the driver removes
pressure from the accelerator pedal. Exhaust
braking is most effective when the engine RPM
is higher. The automatic transmission will down -
shift more aggressively in TOW/HAUL mode
when the exhaust brake is enabled to increase
brake performance. 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).
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
damage5

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212STARTING AND OPERATING
Overdrive Operation
The automatic transmission includes an elec -
tronically 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.
Vehicle speed is sufficiently high.
The TOW/HAUL switch has not been
activated.
The driver is not heavily pressing the
accelerator.
Torque Converter Clutch
A feature designed to improve fuel economy
has been included in the automatic transmis -
sion on your vehicle. A clutch within the torque
converter engages automatically at calibrated
speeds. This may result in a slightly different feeling or response during normal operation in
the upper gears. When the vehicle speed drops
or during some accelerations, the clutch auto
-
matically disengages.
NOTE:
The torque converter clutch will not engage,
until the transmission fluid and engine
coolant are warm (usually after 1 to 3 miles
(2 to 5 km) of driving). Because engine speed
is higher when the torque converter clutch is
not engaged, it may seem as if the transmis -
sion is not shifting properly when cold. This is
normal. Using the Electronic Range Select
(ERS) shift control, when the transmission is
sufficiently warm, will demonstrate that the
transmission is able to shift into and out of
Overdrive.
If the vehicle has not been driven for several
days, the first few seconds of operation after
shifting the transmission into gear may seem
sluggish. This is due to the fluid partially
draining from the torque converter into the
transmission. This condition is normal and
will not cause damage to the transmission.
The torque converter will refill within five
seconds after starting the engine.
When To Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer,
carrying a heavy load, etc., and frequent trans -
mission shifting occurs, push the TOW/HAUL
switch to activate TOW/HAUL mode. This will
improve performance and reduce the potential
for transmission overheating or failure due to
excessive shifting. When operating in TOW/
HAUL mode, transmission upshifts are delayed,
and the transmission will automatically down -
shift (for engine braking) when the throttle is
closed and/or during steady braking maneu -
vers.

TOW/HAUL Switch

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IN CASE OF EMERGENCY311
F68 –10 Amp Red AEB RACAM HTR – If Equipped (HD Only)
F69 –15 Amp Blue SCR Module – If Equipped (HD Only)
F70 –30 Amp GreenFuel Pump Motor / K09 RLY Coil Feed (Cummins Diesel) –
If Equipped
F71 –25 Amp ClearAmplifier / Active Noise Cancelation – If Equipped (HD
Only)
F72 –10 Amp RedPCM / DC/DC Converter Voltage– If Equipped (DS 1500
Only)
F73 –20 Amp Yellow Fuel Transfer Pump (Rear Tank) – If Equipped (HD Only)
F74 –20 Amp Yellow Brake Vacuum Pump Gas/Diesel – If Equipped (DS 1500
Only)
F74 –10 Amp Red Backup Alarm – If Equipped (HD Only)
F75 –10 Amp RedATMM / Coil-SCR Module RLY– If Equipped (HD Only)
Coolant Temperature Valve – If Equipped (DS 1500 Only)
F76 –10 Amp RedElectronic Stability Control (HD Only)
Brake System Module / Stop Lamp Switch / Electric Park
Brake / Clutch Pedal Switch (DS 1500 Only)
F77 –10 Amp Red
Drivetrain Control Module / Front Axle Disconnect Module /
TCM/ STOM (HD Only)

Drivetrain Control Module / ELSD / Front Axle Disconnect
Module / Transmission Control Relay / RDM / Power Take
Off Unit – If Equipped (DS 1500 Only)
Cavity
Cartridge Fuse Micro Fuse Description
6

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322IN CASE OF EMERGENCY
NOTE:
There are steps that you can take to slow down
an impending overheat condition:
If your Air Conditioner (A/C) is on, turn it off.
The A/C system adds heat to the engine
cooling system and turning the A/C off can
help remove this heat.
You can also turn the temperature control to
maximum heat, the mode control to floor and
the blower control to high. This allows the
heater core to act as a supplement to the
radiator and aids in removing heat from the
engine cooling system.
GEAR SELECTOR OVERRIDE — 6–SPEED
TRANSMISSION
If a malfunction occurs and the gear selector
cannot be moved out of the PARK position, you
can use the following procedure to temporarily
move the gear selector:

1. Turn the engine OFF.

2. Firmly apply the parking brake.
3. Tilt the steering wheel to the full up position.
4. Press and maintain firm pressure on the
brake pedal. 5. Insert a screwdriver or similar tool into the
access port (ringed circle) on the bottom of
the steering column, and push and hold the
override release lever up.

Gear Selector Override Access Port Location Gear Selector Override Access Port
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.

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329
SERVICING AND MAINTENANCE
SCHEDULED SERVICING — GAS ENGINE
Your vehicle is equipped with an automatic oil
change indicator system. The oil change indi-
cator 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 Condi-
tions can cause the change oil message to illu -
minate 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 sched
-
uled oil change. If a scheduled oil change is
performed by someone other than an autho -
rized dealer, the message can be reset by refer -
ring to the steps described under “Instrument
Cluster Display” in “Getting To Know Your
Instrument Panel” for further information.
Gas Engines:
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:
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 predominately at idle or very low
engine RPM. This type of vehicle use is consid -
ered Severe Duty. Once A Month Or Before A Long Trip:Check engine oil level.
Check windshield washer fluid level.
Check the tire inflation pressures and look
for unusual wear or damage. Rotate at the
first sign of irregular wear.
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
lights.
7

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SERVICING AND MAINTENANCE363
NOTE:
Intentional tampering with emissions control
systems can result in civil penalties being
assessed against you.
In unusual situations involving grossly malfunc -
tioning engine operation, a scorching odor may
suggest severe and abnormal catalyst over -
heating. If this occurs, stop the vehicle, turn off
the engine and allow it to cool. Service,
including a tune-up to manufacturer's specifica-
tions, 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 Engine Coolant Checks
Check the engine coolant (antifreeze) protec-
tion every 12 months (before the onset of
freezing weather, where applicable). If the
engine coolant (antifreeze) is dirty or rusty in
appearance, the system should be drained,
flushed and refilled with fresh coolant. Check
the front of the A/C condenser (if equipped) or
radiator for any accumulation of bugs, leaves,
etc. If dirty, clean by gently spraying water from
a garden hose vertically down the face of the A/
C condenser (if equipped) or the back of the
radiator core.
Check the engine cooling system hoses for
brittle rubber, cracking, tears, cuts and tight-
ness of the connection at the coolant recovery
bottle and radiator. Inspect the entire system
for leaks.
DO NOT REMOVE THE COOLANT PRESSURE CAP
WHEN THE COOLING SYSTEM IS HOT. 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

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SERVICING AND MAINTENANCE365
(Continued)
Mix a minimum solution of 50% OAT engine
coolant that meets the requirements of FCA
Material Standard MS.90032 and distilled
water. Use higher concentrations (not to
exceed 70%) if temperatures below −34°F
(−37°C) are anticipated. Please contact an
authorized dealer for assistance.
Use only high purity water such as distilled or
deionized water when mixing the water/
engine coolant (antifreeze) solution. The use
of lower quality water will reduce the amount
of corrosion protection in the engine cooling
system.
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.
Some vehicles require special tools to add
coolant properly. Failure to fill these systems
properly could lead to severe internal engine
damage. If any coolant is needed to be added
to the system, please contact a local autho -
rized dealer.
Mixing engine coolant (antifreeze) types is
not recommended and can result in cooling
system damage. If HOAT and OAT coolant are
mixed in an emergency, have an authorized
dealer drain, flush, and refill with OAT coolant
(conforming to MS.90032) as soon as
possible.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss
of engine coolant (antifreeze), and to ensure
that engine coolant (antifreeze) will return to
the radiator from the coolant expansion bottle/
recovery tank if so equipped.
The cap should be inspected and cleaned if
there is any accumulation of foreign material on
the sealing surfaces.
Disposal Of Used Coolant
Used ethylene glycol-based coolant (antifreeze)
is a regulated substance requiring proper
disposal. Check with your local authorities to
determine the disposal rules for your commu -
nity. To prevent ingestion by animals or chil -
dren, do not store ethylene glycol-based coolant
in open containers or allow it to remain in
puddles on the ground. If ingested by a child or
pet, seek emergency assistance immediately.
Clean up any ground spills immediately.
WARNING!
Do not open hot engine cooling system.
Never add engine coolant (antifreeze) when
the engine is overheated. Do not loosen or
remove the cap to cool an overheated
engine. Heat causes pressure to build up in
the cooling system. To prevent scalding or
injury, do not remove the pressure cap
while the system is hot or under pressure.
Do not use a pressure cap other than the
one specified for your vehicle. Personal
injury or engine damage may result.
WARNING! (Continued)
7

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