2020 Ram 3500 automatic transmission

218STARTING AND OPERATING
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.
KEYLESS ENTER-N-GO — IGNITION
This feature allows the driver to operate the
ignition switch with the push of a button, as long
as the Remote Start/Keyless Enter-N-Go key
fob is in the passenger compartment.
Normal Starting
Using The ENGINE START/STOP Button

1. The transmission must be in PARK or NEUTRAL.

2. Press and hold the brake pedal while pushing the ENGINE START/STOP button
once.
3. The system takes over and attempts to start the vehicle. If the vehicle fails to start, the
starter will disengage automatically after
25 seconds. 4. If you wish to stop the cranking of the
engine prior to the engine starting, remove
your foot from the brake pedal and push the
ENGINE START/STOP button again.
NOTE:
Normal starting of either a cold or a warm
engine is obtained without pumping or
pressing the accelerator pedal.
Under cold weather conditions, the engine
may not immediately crank if the “Wait To
Start” telltale is illuminated. This is normal
operation. For vehicles equipped with
Keyless Enter-N-Go, the vehicle will automat -
ically crank when the “Wait To Start” time has
elapsed. See the section “Starting Procedure
— Engine Manifold Air Temperature 0°F to
66°F (-18°C to 19°C)” for more information.
To Turn Off The Engine Using ENGINE START/
STOP Button

1. Place the gear selector in PARK, then push and release the ENGINE START/STOP
button.

2. The ignition will return to the OFF mode. 3. If the gear selector is not in PARK and the
ENGINE START/STOP button is pushed
once, the instrument cluster will display a
“Vehicle Not In Park” message and the
engine will remain running. Never leave a
vehicle out of the PARK position, or it could
roll.
4. If the gear selector is in NEUTRAL, and the vehicle speed below 5 mph (8 km/h),
pushing the ENGINE START/STOP button
once will turn the engine off. The ignition will
remain in the ACC mode.

5. If the vehicle speed is above 5 mph (8 km/h), the ENGINE START/STOP button must be
held for two seconds (or three short pushes
in a row) to turn the engine off. The ignition
will remain in the ACC mode (NOT the OFF
mode) if the engine is turned off when the
transmission is not in PARK.

NOTE:
If the ignition is left in the ACC or ON/RUN
(engine not running) mode and the transmis -
sion is in PARK, the system will automatically
time out after 30 minutes of inactivity and the
ignition return to the OFF mode.

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220STARTING AND OPERATING
5. After engine start-up, check to see that
there is oil pressure.
6. 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.
The engine will not automatically crank after
the engine “Wait To Start” telltale goes off if
a door or the hood is ajar.

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 7 of
“Keyless Enter-N-Go Starting Procedure –
Engine Manifold Air Temperature Below 66° F
(19° C).”

EXTREME COLD WEATHER
The Cummins® Turbo Diesel engine is
equipped with several features designed to
assist cold weather starting and operation:
The engine block heater is a resistance
heater installed in the water jacket of the
engine just above and behind the oil filter. It
requires a 110–115 Volt AC electrical outlet
with a grounded, three-wire extension cord.
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.
A 12 Volt heater built into the fuel filter hous -
ings aid in preventing fuel gelling. It is
controlled by a built-in thermostat.
A intake air heater system both improves
engine starting and reduces the amount of
white smoke generated by a warming engine.
NORMAL STARTING PROCEDURE —
E
NGINE MANIFOLD AIR TEMPERATURE
A
BOVE 66° F (19° C)
Observe the instrument panel cluster lights
when starting the engine.

1. Always apply the parking brake.

2. Shift into PARK for an automatic
transmission.
3. Place the ignition switch in the ON position and watch the instrument panel cluster
lights.
4. Place the ignition switch in the START position and crank the engine. Do not press
the accelerator during starting.
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.

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STARTING AND OPERATING225
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 recommended (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
conditions. 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 an 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.
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
approximately 2 minutes under more severe
cold conditions.
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226STARTING AND OPERATING
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
automatically 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 km/h). 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
automatically 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
aftertreatment 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.

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

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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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232STARTING AND OPERATING
DIESEL EXHAUST BRAKE — ENGINE
BRAKING (IF EQUIPPED)
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
illuminated and the vehicle is moving faster
than 5 mph (8 km/h); the exhaust brake will
automatically 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
downshift more aggressively in TOW/HAUL
mode when the exhaust brake is enabled to
increase brake performance.
Do not leave the key fob in or near the
vehicle, or in a location accessible to chil-
dren, and do not leave 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.
Be sure the parking brake is fully disen -
gaged before driving; failure to do so can
lead to brake failure and a collision.
Always fully apply the parking brake when
leaving your vehicle or it may roll and cause
damage or injury. Also, be certain to leave
the transmission in PARK. Failure to do so
may cause the vehicle to roll and cause
damage or injury.
CAUTION!
If the Brake System Warning Light remains on
with the parking brake released, a brake
system malfunction is indicated. Have the
brake system serviced by an authorized
dealer immediately.
WARNING! (Continued)

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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

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STARTING AND OPERATING235
BRAKE/TRANSMISSION SHIFT
I
NTERLOCK SYSTEM
This vehicle is equipped with a Brake
Transmission Shift Interlock System (BTSI) that
holds the transmission gear selector in PARK
unless the brakes are applied. To shift the
transmission out of PARK, the engine must be
running and the brake pedal must be pressed.
The brake pedal must also be pressed to shift
from NEUTRAL into DRIVE or REVERSE when the
vehicle is stopped or moving at low speeds.
EIGHT-SPEED AUTOMATIC
T
RANSMISSION — IF EQUIPPED
The transmission is controlled using a rotary
electronic gear selector located on the
instrument panel. The transmission gear range
(PRND) is displayed both above the gear
selector and in the instrument cluster. To select
a gear range, simply rotate the gear selector.
You must press the brake pedal to shift the
transmission out of PARK (or NEUTRAL, when
the vehicle is stopped or moving at low speeds).
To shift past multiple gear ranges at once (such
as PARK to DRIVE), simply rotate the gear
selector to the appropriate detent. Select the
DRIVE range for normal driving. NOTE:
In the event of a mismatch between the gear
selector position and the actual transmission
gear (for example, driver selects PARK while
driving), the position indicator will blink continu
-
ously until the selector is returned to the proper
position, or the requested shift can be
completed.
The electronically-controlled transmission
adapts its shift schedule based on driver inputs,
along with environmental and road conditions.
The transmission electronics are
self-calibrating; therefore, the first few shifts on
a new vehicle may be somewhat abrupt. This is
a normal condition, and precision shifts will
develop within a few hundred miles
(kilometers).

Only shift from DRIVE to PARK or REVERSE when
the accelerator pedal is released and the vehicle
is stopped. Be sure to keep your foot on the brake
pedal when shifting between these gears.

The transmission gear selector has only PARK,
REVERSE, NEUTRAL, and DRIVE positions.
Manual downshifts can be made using the
Electronic Range Select (ERS) shift control.
Pressing the GEAR -/GEAR + switches (on the
steering wheel) while in the DRIVE position will select the highest available transmission gear,
and will display that gear limit in the instrument
cluster as 1, 2, 3, etc. Refer to “Electronic
Range Select (ERS) Operation” in this section
for further information. Some models will
display both the selected gear limit, and the
actual current gear, while in ERS mode.

Electronic Transmission Gear Selector

Gear Ranges
Do not depress the accelerator pedal when
shifting from PARK or NEUTRAL into another
gear range.
NOTE:
After selecting any gear range, wait a moment
to allow the selected gear to engage before
accelerating. This is especially important when
the engine is cold.
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