engine RAM 1500 2021 Workshop Manual

146STARTING AND OPERATING
(Continued)
COLD WEATHER OPERATION (BELOW
–22°F O
R −30°C)
To ensure reliable starting at these
temperatures, use of an externally powered
electric engine block heater (available from an
authorized dealer) is recommended.
AFTER STARTING
The idle speed is controlled automatically, and
it will decrease as the engine warms up.
STARTING FLUIDS — DIESEL ENGINE
O
NLY
The engine is equipped with a glow plug
preheating system. If the instructions in this
manual are followed, the engine should start in
all conditions and no type of starting fluid
should be used.
NORMAL OPERATION — DIESEL ENGINE
Observe the following when the diesel engine is
operating.
All message center lights are off.
Malfunction Indicator Light (MIL) is off.
Engine Oil Pressure telltale is not illuminated.
Voltmeter operation:
The voltmeter may show a gauge fluctuation at
various engine temperatures. This is caused by
the glow plug heating system. The number of
cycles and the length of the cycling operation is
controlled by the engine control module. Glow
plug heater operation can run for several
minutes, once the heater operation is complete
the voltmeter needle will stabilize.
COLD WEATHER PRECAUTIONS
Operation in ambient temperature below 32°F
(0°C) may require special considerations. The
following charts suggest these options:
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 make
sure the wireless 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.
WARNING! (Continued)

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148STARTING AND OPERATING
NOTE:
Use of Climatized ULSD Fuel or Number
1 ULSD Fuel results in a noticeable decrease
in fuel economy.
Climatized ULSD Fuel is a blend of Number
2 ULSD and Number 1 ULSD Fuels which
reduces the temperature at which wax crys -
tals form in fuel.
The fuel grade should be clearly marked on
the pump at the fuel station.
The engine requires the use of ULSD Fuel.
Use of incorrect fuel could result in engine
and exhaust system damage Ú page 471.
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).
Engine Oil Usage
For the correct engine oil viscosity Úpage 475.
Winter Front Cover

Winter Front Cover

A Winter front or cold weather cover can 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
in the full open position to allow air flow to the
cooling module 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 a
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.
If temperatures are below 32°F (0°C), operate
the engine at moderate speeds for five minutes
before full loads are applied.
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, cylinder head
valves, and injector nozzles. Also, the unburned
fuel can enter the crankcase, diluting the oil
and causing rapid wear to the engine.
STOPPING THE ENGINE
After full load operation, idle the engine for a
few minutes before shutting it down. This idle
period will allow the lubricating oil and coolant
to carry excess heat away from the
turbocharger. Refer to the following chart for
proper engine shutdown.

21_DT_OM_EN_USC_t.book Page 148

STARTING AND OPERATING149
NOTE:
Under certain conditions the engine fan will run
after the engine is turned off. These conditions
are under high load and high temperature
conditions.
Do Not Operate The Engine With Low Oil
Pressure
If the low oil pressure warning light turns on
while driving, stop the vehicle and shut down
the engine as soon as possible. A chime will
sound when the light turns on. NOTE:
Do not operate the vehicle until the cause is
corrected. This light does not show how much
oil is in the engine. The engine oil level must be
checked under the hood.
Do Not Operate The Engine With Failed
Parts
All engine failures give some warning before the
parts fail. Some important observations are:
Engine misfiring or vibrating severely
Sudden loss of power
Unusual engine noises
Fuel, oil or coolant leaks
Sudden change, outside the normal operating
range, in the engine operating temperature
Excessive smoke
Oil pressure drop
Driving Condition
Load Turbocharger Temperature Idle Time (min.) Before Engine
Shutdown
Stop and Go EmptyCoolNone
Stop and Go Medium 0.5
Highway Speeds MediumWarm 1.0
City Traffic Maximum GCWR 1.5
Highway Speeds Maximum GCWR 2.0
Uphill Grade Maximum GCWR Hot2.5
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.
4

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150STARTING AND OPERATING
ENGINE BLOCK HEATER — IF EQUIPPED

Engine Block Heater Cord Location

The engine block heater warms engine coolant
and permits quicker starts in cold weather.
Connect the heater cord to a ground-fault
interrupter protected 110–115 Volt AC
electrical outlet with a grounded, three-wire
extension cord.
For diesel engines, its use is recommended for
environments that routinely fall below -10°F
(-23°C). It should be used when the vehicle has
not been running for long periods of time and
should be plugged in two hours prior to start. Its
use is required for cold starts with temperatures
under -20°F (-28°C). To ensure reliable starting at these
temperatures, use of an externally powered
electric engine block heater (available from an
authorized dealer) is recommended.
The engine block heater cord is routed under
the hood on the passenger side of the vehicle
next to the engine coolant reservoir.
ENGINE BREAK-IN RECOMMENDATIONS —
GASOLINE 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
Ú
page 475.
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.
WARNING!
Remember to disconnect the engine block
heater cord before driving. Damage to the
110-115 Volt electrical cord could cause
electrocution.
CAUTION!
Never use Non-Detergent Oil or Straight
Mineral Oil in the engine or damage may
result.

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STARTING AND OPERATING151
ENGINE BREAK-IN RECOMMENDATIONS —
DIESEL ENGINE
The 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.
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.
NOTE:
Light duty operation such as light trailer towing
or no load operation will extend the time before
the engine is at full efficiency. Reduced fuel
economy and power may be seen at this time.
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
Ú
page 475.
NOTE:
NON-DETERGENT OR STRAIGHT MINERAL OILS
MUST NEVER BE USED.
PARKING BRAKE
ELECTRIC PARK BRAKE (EPB)
Your vehicle is equipped with an EPB that offers
simple operation, and some additional features
that make the parking brake more convenient
and useful.
The parking brake is primarily intended to
prevent the vehicle from rolling while parked.
Before leaving the vehicle, make sure that the
parking brake is applied. Also, be certain to
leave the transmission in PARK.
You can engage the parking brake in two ways:
Manually, by applying the parking brake
switch.
Automatically, by enabling the Auto Park
Brake feature in the customer programmable
features section of the Uconnect settings. The parking brake switch is located on the
instrument panel to the left of the steering
wheel (below the headlamp switch).

Electric Park Brake Switch

To apply the parking brake manually, pull up on
the switch momentarily. You may hear a slight
sound from the back of the vehicle while the
parking brake engages. Once the park brake is
fully engaged, the BRAKE telltale light in the
instrument cluster and an indicator on the
switch will illuminate. If your foot is on the brake
pedal while you apply the parking brake, you
may notice a small amount of brake pedal
movement. The parking brake can be applied
even when the ignition switch is OFF but the
BRAKE telltale light will not illuminate, however,
it can only be released when the ignition is in
the ON/RUN mode.
4

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154STARTING AND OPERATING
(Continued)
(Continued)
Fortunately, actuator retraction can be done
easily by entering the Brake Service Mode
through the Uconnect Settings in your vehicle.
This menu based system will guide you through
the steps necessary to retract the EPB actuator
in order to perform rear brake service.
Service Mode has requirements that must be
met in order to be activated:
The vehicle must be at a standstill.
The parking brake must be unapplied.
The transmission must be in PARK or
NEUTRAL.
While in Service Mode, the EPB fault lamp will
flash continuously while the ignition is ON.
When brake service work is complete, the
following steps must be followed to reset the
park brake system to normal operation:
Ensure the vehicle is at a standstill.
Press the brake pedal with moderate force.
Apply the EPB Switch.
AUTOMATIC TRANSMISSION
You must press and hold the brake pedal while
shifting out of PARK.
WARNING!
You can be badly injured working on or
around a motor vehicle. Do only that service
work for which you have the knowledge and
the right equipment. If you have any doubt
about your ability to perform a service job,
take your vehicle to a competent mechanic.
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.
It is dangerous to shift out of PARK or
NEUTRAL if the engine speed is higher than
idle speed. If your foot is not firmly pressing
the brake pedal, the vehicle could accel -
erate quickly forward or in reverse. You
could lose control of the vehicle and hit
someone or something. Only shift into gear
when the engine is idling normally and your
foot is firmly pressing the brake pedal.
WARNING! (Continued)

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STARTING AND OPERATING155
(Continued)
IGNITION PARK INTERLOCK
This vehicle is equipped with an Ignition Park
Interlock which requires the transmission to be
in PARK before the ignition can be turned to the
OFF mode. This helps the driver avoid
inadvertently leaving the vehicle without placing the transmission in PARK. This system also
locks the transmission in PARK whenever the
ignition is in the OFF mode.
NOTE:
The transmission is NOT locked in PARK when
the ignition is in the ACC mode (even though the
engine will be off). Ensure that the transmission
is in PARK, and the ignition is OFF (not in ACC
mode) before exiting the vehicle.
BRAKE/TRANSMISSION SHIFT
I
NTERLOCK SYSTEM
This vehicle is equipped with a Brake
Transmission Shift Interlock (BTSI) system 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.
Unintended movement of a vehicle could
injure those in or near the vehicle. As with
all vehicles, you should never exit a vehicle
while the engine is running. Before exiting a
vehicle, always come to a complete stop,
then apply the parking brake, shift the
transmission into PARK, and turn the igni -
tion OFF. When the ignition is in the OFF
mode, the transmission is locked in PARK,
securing the vehicle against unwanted
movement.
When exiting the vehicle, always make sure
the ignition 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 transmission gear
selector.
WARNING! (Continued)
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 in the
ACC or ON/RUN mode. A child could
operate power windows, other controls, or
move the vehicle.
CAUTION!
Shift into or out of PARK or REVERSE only
after the vehicle has come to a complete
stop.
Do not shift between PARK, REVERSE,
NEUTRAL, or DRIVE when the engine is
above idle speed.
Before shifting into any gear, make sure
your foot is firmly pressing the brake pedal.
WARNING! (Continued)
4

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156STARTING AND OPERATING
EIGHT-SPEED AUTOMATIC
T
RANSMISSION
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 Ú
page 159. 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 press 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.
PARK (P)
This range supplements the parking brake by
locking the transmission. The engine can be
started in this range. Never attempt to use PARK
while the vehicle is in motion. Apply the parking
brake when exiting the vehicle in this range.

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STARTING AND OPERATING157
(Continued)
(Continued)
(Continued)
When parking on a hill, apply the parking brake
before shifting the transmission to PARK. As an
added precaution, turn the front wheels toward
the curb on a downhill grade and away from the
curb on an uphill grade.
NOTE:
On four-wheel drive vehicles be sure that the
transfer case is in a drive position.
When exiting the vehicle, always:
Apply the parking brake.
Shift the transmission into PARK.
Turn the engine off.
Remove the key fob from the vehicle.
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.
It is dangerous to shift out of PARK or
NEUTRAL if the engine speed is higher than
idle speed. If your foot is not firmly pressing
the brake pedal, the vehicle could accel -
erate quickly forward or in reverse. You
could lose control of the vehicle and hit
someone or something. Only shift into gear
when the engine is idling normally and your
foot is firmly pressing the brake pedal.
WARNING! (Continued)
Unintended movement of a vehicle could
injure those in or near the vehicle. As with
all vehicles, you should never exit a vehicle
while the engine is running. Before exiting a
vehicle, always come to a complete stop,
then apply the parking brake, shift the
transmission into PARK, and turn the igni -
tion OFF. When the ignition is in the OFF
mode, the transmission is locked in PARK,
securing the vehicle against unwanted
movement.
When exiting the vehicle, always make sure
the ignition 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 transmission gear
selector.
WARNING! (Continued)
4

21_DT_OM_EN_USC_t.book Page 157

158STARTING AND OPERATING
The following indicators should be used to
ensure that you have properly engaged the
transmission into the PARK position:
Look at the transmission gear position
display and verify that it indicates the PARK
position (P), and is not blinking.
With brake pedal released, verify that the
gear selector will not move out of PARK.
REVERSE (R)
This range is for moving the vehicle backward.
Shift into REVERSE only after the vehicle has
come to a complete stop.
NEUTRAL (N)
Use this range when the vehicle is standing for
prolonged periods with the engine running.
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 all forward gears.
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), select TOW/HAUL mode or use
the Electronic Range Select (ERS) shift control
to select a lower gear range
Úpage 159. Under
these conditions, using a lower gear range will
improve performance and extend transmission
life by reducing excessive shifting and heat
buildup.
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 in the
ACC or ON/RUN mode. A child could
operate power windows, other controls, or
move the vehicle.
CAUTION!
DO NOT race the engine when shifting from
PARK or NEUTRAL into another gear range,
as this can damage the drivetrain.
Before moving the transmission gear
selector out of PARK, you must start the
engine, and also press the brake pedal.
Otherwise, damage to the gear selector
could result.
WARNING! (Continued)
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.
For Recreational Towing Ú page 231.
For Towing A Disabled Vehicle Ú page 392.

21_DT_OM_EN_USC_t.book Page 158