2020 Ram 3500 cooling

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)

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242STARTING AND OPERATING
NEUTRAL (N)
Use this range when the vehicle is standing for
prolonged periods with the engine running. The
engine may be started in this range. Apply the
parking brake and shift the transmission into
PARK if you must exit the vehicle. DRIVE (D)
This range should be used for most city and
highway driving. It provides the smoothest
upshifts and downshifts, and the best fuel
economy. The transmission automatically
upshifts through underdrive first, second, and
third gears, direct fourth gear and overdrive fifth
and sixth gears. The DRIVE position provides
optimum driving characteristics under all
normal operating conditions.
When frequent transmission shifting occurs
(such as when operating the vehicle under
heavy loading conditions, in hilly terrain,
traveling into strong head winds, or while towing
a heavy trailer), use the Electronic Range Select
(ERS) shift control refer to “Electronic Range
Select (ERS) Operation” in this section for
further information to select a lower gear range.
Under these conditions, using a lower gear
range will improve performance and extend
transmission life by reducing excessive shifting
and heat buildup.If the transmission temperature exceeds
normal operating limits, the powertrain
controller will modify the transmission shift
schedule and expand the range of torque
converter clutch engagement. This is done to
prevent transmission damage due to
overheating.
If the transmission becomes extremely hot or is
in danger of overheating, the “Transmission
Temperature Warning Light” may illuminate and
the transmission may operate differently until
the transmission cools down.
NOTE:
Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer
up a steep grade, or in stop-and-go traffic)
during hot weather. In these conditions, torque
converter slip can impose a significant addi
-
tional heat load on the cooling system. Down -
shifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to
NEUTRAL (when stopped in heavy traffic) can
help to reduce this excess heat generation.
WARNING!
Do not coast in NEUTRAL and never turn off
the ignition to coast down a hill. These are
unsafe practices that limit your response to
changing traffic or road conditions. You might
lose control of the vehicle and have a
collision.
CAUTION!
Towing the vehicle, coasting, or driving for any
other reason with the transmission in
NEUTRAL can cause severe transmission
damage. Refer to “Recreational Towing” in
“Starting And Operating” and “Towing A
Disabled Vehicle” in “In Case Of Emergency”
for further information.

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STARTING AND OPERATING267
Crossing Puddles, Pools, Flooded Areas Or
Other Standing Water – Puddles, pools,
flooded or other standing water areas
normally contain murky or muddy waters.
These water types normally contain hidden
obstacles and make it difficult to determine
an accurate water depth, approach angle,
and bottom condition. Murky or muddy water
holes are where you want to hook up tow
straps prior to entering. This makes for a
faster, cleaner and easier vehicle recovery. If
you are able to determine you can safely
cross, than proceed using the low and slow
method.
Crossing Ditches, Streams, Shallow Rivers Or
Other Flowing Water – Flowing water can be
extremely dangerous. Never attempt to cross
a fast running stream or river even in shallow
water. Fast moving water can easily push
your vehicle downstream sweeping it out of
control. Even in very shallow water, a high
current can still wash the dirt out from around your tires putting you and your vehicle
in jeopardy. There is still a high risk of
personal injury and vehicle damage with
slower water currents in depths greater than
the vehicle's running ground clearance. You
should never attempt to cross flowing water
which is deeper than the vehicle's running
ground clearance. Even the slowest current
can push the heaviest vehicle downstream
out of control if the water is deep enough to
push on the large surface area of the
vehicle's body. Before you proceed deter
-
mine the speed of the current, the water's
depth, approach angle, bottom condition and
if there are any obstacles, then cross at an
angle heading slightly upstream using the
low and slow technique.
AIRING DOWN FOR OFF-ROAD DRIVING

Running lower tire pressure off-road can improve
your ride comfort and vehicle traction. Reducing
the tire air pressure allows the tire to bulge
slightly, improving its surface area for better
flotation and ability to mold or form to the ground
contour. Different terrain, tires, and vehicles
require different tire pressure. Hard surfaces like
rock and heavier vehicles require higher
pressures than softer surfaces such as sand and
lighter vehicles. You will need to experiment to
determine what is right for your situation. It is
easier and faster to let air out than it is to replace
it. Start high and lower it as required. Remember
you must return the tires to normal air pressure
before driving on road or at highway conditions.
Be sure you have a way to return the tires to their
normal on road air pressure.

CAUTION!
Muddy waters can reduce the cooling system
effectiveness by depositing debris onto the
radiator.
WARNING!
Never drive through fast moving deep water. It
can push your vehicle downstream, sweeping
it out of control. This could put you and your
passengers at risk of injury or drowning.CAUTION!
Reduced tire pressure increases the risk of
tire damage and may cause tire unseating
with total loss of air pressure. To reduce the
risk of tire unseating, while at a reduced tire
pressure, drive at slower speeds and avoid
sharp turns or abrupt maneuvers.
5

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336STARTING AND OPERATING
TOWING TIPS
Before setting out on a trip, practice turning,
stopping, and backing up the trailer in an area
located away from heavy traffic.
Automatic Transmission
The DRIVE range can be selected when towing.
The transmission controls include a drive
strategy to avoid frequent shifting when towing.
However, if frequent shifting does occur while in
DRIVE, select TOW/HAUL mode or select a lower
gear range (using the Electronic Range Select
[ERS] shift control).
NOTE:
Using TOW/HAUL mode or selecting a lower
gear range (using the ERS shift control) while
operating the vehicle under heavy loading
conditions will improve performance and
extend transmission life by reducing excessive
shifting and heat build-up. This action will also
provide better engine braking.
Tow/Haul Mode
To reduce potential for automatic transmission
overheating, activate TOW/HAUL mode when
driving in hilly areas, or select a lower gear
range (using the Electronic Range Select [ERS]
shift control) on more severe grades.
Speed Control — If Equipped
Do not use on hilly terrain or with heavy
loads.
When using the Speed Control, if you experi -
ence speed drops greater than 10 mph
(16 km/h), disengage until you can get back
to cruising speed.
Use Speed Control in flat terrain and with
light loads to maximize fuel efficiency.
Cooling System
To reduce potential for engine and transmission
overheating, take the following actions: City Driving
In city traffic — while stopped, place the trans
-
mission in NEUTRAL, but do not increase
engine idle speed.
Highway Driving
Reduce speed.
Temporarily turn off air conditioning.
Air Suspension System
To aid in attaching/detaching the trailer from
the vehicle, the air suspension system can be
used. Refer to “Air Suspension System” in
“Starting And Operating” for further
information.
NOTE:
The vehicle must remain in the engine running
position while attaching a trailer for proper
leveling of the air suspension system.

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IN CASE OF EMERGENCY375
(Continued)
Replace the wheel covers using a rubber mallet
to ease the installation. Align the wheel cover
vent holes to the wheel vent holes. Tap on the
wheel cover as needed to firmly seat it evenly
around the wheel.
JUMP STARTING
If your vehicle has a discharged battery, it can
be jump started using a set of jumper cables
and a battery in another vehicle, or by using a
portable battery booster pack. Jump starting
can be dangerous if done improperly, so please
follow the procedures in this section carefully. NOTE:
When using a portable battery booster pack,
follow the manufacturer's operating instruc
-
tions and precautions.
PREPARATIONS FOR JUMP START
The battery in your vehicle is located in the front
of the engine compartment, behind the driver
side headlight assembly.
NOTE:
If you have a diesel engine, you may have two
batteries, however jump start off the driver
side battery.
The positive battery post may be covered with
a protective cap if equipped. Lift up on the
cap to gain access to the positive battery
post. Do not jump off fuses. Only jump
directly off positive post which has a positive
(+) symbol on or around the post.

Positive Battery Post

The rear hub caps on the dual rear wheel
has two pull off notches. Make sure that the
hook of the jack handle driver is located
squarely in the cap notch before attempting
to pull off.
WARNING!
Do not attempt jump starting if the battery is
frozen. It could rupture or explode and cause
personal injury.
CAUTION! (Continued)CAUTION!
Do not use a portable battery booster pack or
any other booster source with a system
voltage greater than 12 Volts or damage to
the battery, starter motor, alternator or
electrical system may occur.
WARNING!
Take care to avoid the radiator cooling fan
whenever the hood is raised. It can start
anytime the ignition switch is ON. You can
be injured by moving fan blades.
6

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IN CASE OF EMERGENCY379
4. Using the screwdriver or similar tool, push
the Manual Park Release lever locking tab
(just below the middle of the lever) to the
right.

Manual Park Release Pull Tether

5. While holding the locking tab in the disengaged position, pull the tether strap to
rotate the lever rearward, until it locks in
place pointing towards the driver's seat.
Release the locking tab and verify that the
Manual Park Release lever is locked in the
released position.
6. The vehicle is now out of PARK and can be towed. Release the parking brake only when
the vehicle is securely connected to a tow
vehicle. To Reset The Manual Park Release:

1. Push the locking tab to the right, to unlock
the lever.

2. Rotate the Manual Park Release lever forward to its original position, until the
locking tab snaps into place to secure the
lever.
3. Pull gently on the tether strap to confirm that the lever is locked in its stowed
position.

Manual Park Release Pull Strap

4. Re-install the access cover.IF YOUR ENGINE OVERHEATS
In any of the following situations, you can
reduce the potential for overheating by taking
the appropriate action.
On the highways — slow down.
In city traffic — while stopped, place the trans -
mission in NEUTRAL, but do not increase the
engine idle speed while preventing vehicle
motion with the brakes.
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.
6

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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.

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386SERVICING AND MAINTENANCE
MAINTENANCE PLAN — GASOLINE ENGINE
Required Maintenance
Refer to the Maintenance Plan on the following pages for required maintenance. More frequent maintenance may be needed in severe conditions, such
as dusty areas and very short trip driving. In some extreme conditions, additional maintenance not specified in the maintenance schedule may be
required.
NOTE:
Using white lithium grease, lubricate the door hinge roller pivot joints twice a year to prevent premature wear.
At Every Oil Change Interval As Indicated By Oil Change Indicator System:
Change oil and filter.
Rotate the tires. Rotate at the first sign of irregular wear, even if it occurs before the oil indicator system turns on.
Inspect battery and clean and tighten terminals as required.
Inspect the CV/Universal joints.
Inspect brake pads, shoes, rotors, drums, hoses and park brake.
Inspect engine cooling system protection and hoses.
Inspect exhaust system.
Inspect engine air cleaner if using in dusty or off-road conditions. If required, replace air cleaner filter.
Inspect and replace the Evaporative System Fresh Air Filter as necessary, replacement may be more frequent if vehicle is operated in extreme
dusty conditions.

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