2020 Ram 3500 Chassis Cab engine overheat

GETTING TO KNOW YOUR INSTRUMENT PANEL113
Low Washer Fluid Warning Light — If
Equipped
This warning light will illuminate when
the windshield washer fluid is low.
Refer to “Engine Compartment” in “Servicing
And Maintenance” for further information.
Low Fuel Warning Light
When the fuel level reaches approxi -
mately 3.2 gal (12 L) this light will turn
on, and remain on until fuel is added.
A single warning chime will sound with Low Fuel
Warning.
Low Coolant Level Warning Light
This telltale will turn on to indicate the
vehicle coolant level is low.
Refer to “Dealer Service” in “Servicing And
Maintenance” for further information.
Loose Fuel Filler Cap Warning Light — If
Equipped
This warning light will illuminate when
the fuel filler cap is loose. Properly
close the filler cap to disengage the light. If the light does not turn off, please see an
authorized dealer.
Tire Pressure Monitoring System (TPMS)
Warning Light — If Equipped
The warning light switches on and a
message is displayed to indicate that
the tire pressure is lower than the
recommended value and/or that slow
pressure loss is occurring. In these cases,
optimal tire duration and fuel consumption may
not be guaranteed.
Should one or more tires be in the condition
mentioned above, the display will show the indi -
cations corresponding to each tire.
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recommended by the vehicle manufacturer on the vehicle
placard or tire inflation pressure label. If your
vehicle has tires of a different size than the size
indicated on the vehicle placard or tire inflation
pressure label, you should determine the
proper tire inflation pressure for those tires.
As an added safety feature, your vehicle has
been equipped with a Tire Pressure Monitoring
System (TPMS) that illuminates a low tire pres
-
sure telltale when one or more of your tires is
significantly under-inflated. Accordingly, when
the low tire pressure telltale illuminates, you
should stop and check your tires as soon as
possible, and inflate them to the proper pres -
sure. Driving on a significantly under-inflated
tire causes the tire to overheat and can lead to
tire failure. Under-inflation also reduces fuel
efficiency and tire tread life, and may affect the
vehicle’s handling and stopping ability.
Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver’s
responsibility to maintain correct tire pressure,
even if under-inflation has not reached the level
to trigger illumination of the TPMS low tire pres -
sure telltale.
CAUTION!
Do not continue driving with one or more flat
tires as handling may be compromised. Stop
the vehicle, avoiding sharp braking and
steering. If a tire puncture occurs, repair
immediately using the dedicated tire repair
kit and contact an authorized dealer as soon
as possible.
3

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183
(Continued)
STARTING AND OPERATING
STARTING THE ENGINE — GAS ENGINE
Before starting your vehicle, adjust your seat,
adjust both inside and outside mirrors, and
fasten your seat belt.
The starter should not be operated for more
than 10-second intervals. Waiting a few
seconds between such intervals will protect the
starter from overheating.
Automatic Transmission
Start the engine with the transmission in PARK
position. Apply the brake before shifting into any
driving range.NOTE:
This vehicle is equipped with a transmission
shift interlocking system. The brake pedal
must be pressed to shift out of PARK.
If equipped with an 8-speed transmission,
starting the vehicle in NEUTRAL is not
possible unless the Manual Park Release has
been activated. For the Manual Park Release
operation refer to Manual Park Release in “In
Case Of Emergency”.
Tip Start Feature
Do not
press the accelerator. Cycle the ignition
switch briefly to the START position and release
it. The starter motor will continue to run and will
automatically disengage when the engine is
running.
WARNING!
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.
Do not leave children or animals inside
parked vehicles in hot weather. Interior
heat build-up may cause serious injury or
death.
WARNING! (Continued)
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STARTING AND OPERATING187
(Continued)
If the engine has been flooded, it may start to
run, but not have enough power to continue
running when the ignition button/key is
released. If this occurs, continue cranking with
the accelerator pedal pushed all the way to the
floor. Release the accelerator pedal and the
ignition button/key once the engine is running
smoothly.
If the engine shows no sign of starting after a 10
second period of engine cranking with the
accelerator pedal held to the floor, wait 10 to 15
seconds, then repeat the “Normal Starting”
procedure.
Cold Weather Operation (Below –22°F Or
−30°C)
To ensure reliable starting at these tempera -
tures, use of an externally powered electric
engine block heater (available from your autho -
rized dealer) is recommended.
After Starting
The idle speed is controlled automatically, and
it will decrease as the engine warms up.
STARTING THE ENGINE — DIESEL ENGINE
Before starting your vehicle, adjust your seat,
adjust both inside and outside mirrors, and
fasten your seat belts.
The starter should not be operated for more
than 25-second intervals. Waiting a few
minutes between such intervals will protect the
starter from overheating.
Automatic Transmission
Start the engine with the transmission in the
NEUTRAL or PARK position. Apply the brake
before shifting to any driving range.
CAUTION!
To prevent damage to the starter, do not
crank the engine for more than 10 seconds at
a time. Wait 10 to 15 seconds before trying
again.
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 remove
the key fob and lock your 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 children), 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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200STARTING AND OPERATING
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.
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.
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.

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210STARTING AND OPERATING
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 over -
heating.
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. During cold temperatures, transmission opera
-
tion may be modified depending on engine and
transmission temperature as well as vehicle
speed. This feature improves warm up time of
the engine and transmission to achieve
maximum efficiency. Engagement of the torque
converter clutch is inhibited until the transmis -
sion fluid is warm (refer to the “Note” under
“Torque Converter Clutch” in this section).
On trucks with AS66RC or AS69RC transmis -
sion, FIFTH and SIXTH gears may be inhibited
briefly on cold starts below 41°F (5°C), and
during very cold temperatures (-4°F [-20°C] or
below), operation may briefly be limited to third
gear only. During this condition, the ability of the
vehicle to accelerate under heavily loaded
conditions may be reduced. In all cases, normal
operation will resume once the transmission
temperature has risen to a suitable level.
Transmission Limp Home Mode
Transmission function is monitored electroni -
cally for abnormal conditions. If a condition is
detected that could result in transmission
damage, Transmission Limp Home Mode is acti -
vated. In this mode, the transmission remains
in third gear (for AS66RC/AS69RC transmis -
sion) regardless of which forward gear is
selected. If an AS66RC/AS69RC equipped truck enters Limp Home Mode at highway speeds, it
will initially engage fifth gear, until the vehicle
slows to a speed where third gear can be
engaged. PARK, REVERSE, and NEUTRAL will
continue to operate. The Malfunction Indicator
Light (MIL) may be illuminated. Limp Home
Mode allows the vehicle to be driven to an
authorized dealer for service without damaging
the transmission.
In the event of a momentary problem, the trans
-
mission can be reset to regain all forward gears
by performing the following steps:

1. Stop the vehicle.

2. Shift the transmission into PARK.
3. Turn the ignition to the OFF position.
4. Wait approximately 10 seconds.
5. Restart the engine.
6. Shift into the desired gear range. If the problem is no longer detected, the trans -
mission will return to normal operation.

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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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218STARTING AND OPERATING
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.

TOW/HAUL Switch

The “TOW/HAUL Indicator Light” will illuminate
in the instrument cluster to indicate that TOW/
HAUL mode has been activated. Pushing the
switch a second time restores normal opera -
tion. Normal operation is always the default at
engine start-up. If TOW/HAUL mode is desired,
the switch must be pushed each time the
engine is started.
AUXILIARY SWITCHES — IF EQUIPPED
There can be up to six auxiliary switches located
in the lower switch bank of the instrument panel
which can be used to power various electronic
devices and PTO (Power Take Off) – If Equipped.
If Power Take Off is equipped, it will take the
place of the sixth Auxiliary switch. Connections
to the switches are found under the hood in the
connectors attached to the auxiliary Power
Distribution Center. You have the ability to configure the function
-
ality of the auxiliary switches via the instrument
cluster display. All switches can now be config -
ured for setting the switch type operation to
latching or momentary, power source of either
battery or ignition, and ability to hold last state
across key cycles.
NOTE:
Holding last state conditions are met when
switch type is set to latching and power source
is set to ignition.
For further information on using the auxiliary
switches, please refer to the Ram Body Builders
Guide by accessing www.rambodybuilder.com
and choosing the appropriate links.
FOUR-WHEEL DRIVE OPERATION — IF
EQUIPPED
Four-wheel drive trucks are equipped with
either a manually shifted transfer case or an
electronically shifted transfer case. Refer to the
operating instructions for your transfer case,
located in this section for further information.
WARNING!
Do not use the “TOW/HAUL” feature when
driving in icy or slippery conditions. 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.

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STARTING AND OPERATING285
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.
Six-Speed Automatic Transmission Only
When towing a loaded trailer up steep grades at
low speeds (20 mph [32 km/h] or below),
holding your vehicle in first gear (using the ERS
shift control) can help to avoid transmission
overheating. If you regularly tow a trailer for more than
45 minutes of continuous operation, then
change the automatic transmission fluid and
filter(s) as specified for "police, taxi, fleet, or
frequent trailer towing." Refer to the “Mainte
-
nance Plan” for the proper maintenance inter -
vals.
NOTE:
Check the automatic transmission fluid level
before towing (Six-speed automatic only).
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.
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