2021 RAM CHASSIS CAB stop start

134STARTING AND OPERATING
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 to 87 mph (64 km/h to
140 km/h). The 4500/5500 Series maximum
vehicle speed can be set between 40 mph to
85 mph (64 km/h to 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.

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STARTING AND OPERATING139
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. 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.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

4

21_DPF_OM_EN_USC_t.book Page 139

140STARTING AND OPERATING
(Continued)
(Continued)
AUTOMATIC TRANSMISSION
You must press and hold the brake pedal while
shifting out of PARK.
WARNING!
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.
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.
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, turn the engine
OFF, and remove the key fob. When the
ignition is in the LOCK/OFF (key removal)
position, (or, with Keyless Enter-N-Go, when
the ignition is in the OFF mode) the trans -
mission is locked in PARK, securing the
vehicle against unwanted movement.
When leaving the vehicle, always make
sure the ignition is in the OFF mode,
remove the key fob from the vehicle, and
lock the vehicle.
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.
WARNING! (Continued)

Your vehicle could move and injure you and
others if it is not in PARK. Check by trying to
move the gear selector out of PARK with the
brake pedal released. Make sure the trans -
mission is in PARK before exiting the vehicle.
Never leave children alone in a vehicle, or
with access to an unlocked vehicle. Allowing
children to be in a vehicle unattended 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 transmis -
sion 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 (in 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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STARTING AND OPERATING141
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 (BTSI) SYSTEM
This vehicle is equipped with a BTSI system that
holds the transmission gear selector in PARK
unless the brakes are applied. For vehicles with
8-speed transmission, 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.
For vehicles with 6-speed transmission, to shift
the transmission out of PARK, the ignition must
be in the ON/RUN mode (engine running or not)
and the brake pedal must be pressed.
The BTSI will timeout if brake pedal is pressed
for three minutes or longer continuously while in
park. It can be reset by releasing the brake for
more then three seconds, then reapplying the
brake pedal or cycling the ignition.
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).

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.
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142STARTING AND OPERATING
(Continued)
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 Úpage 145. 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.
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.
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.

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STARTING AND OPERATING143
(Continued)
(Continued)

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 indi
-
cated, 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 unattended 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 transmis -
sion 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!
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)
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21_DPF_OM_EN_USC_t.book Page 143

144STARTING 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 145. Under
these conditions, using a lower gear range will
improve performance and extend transmission
life by reducing excessive shifting and heat
build-up.
During extremely cold temperatures
(-22°F [-30°C] or below), transmission
operation may be modified depending on
engine and transmission temperature as
well as vehicle speed. Normal operation will
resume once the transmission temperature
has risen to a suitable level.
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 Towing A Disabled Vehicle Ú page 350.
For Recreational Towing Ú page 215.

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STARTING AND OPERATING145
Transmission Limp Home Mode
Transmission function is monitored
electronically for abnormal conditions.
If a condition is detected that could result in
transmission damage, Transmission Limp
Home Mode is activated. In this mode, the
transmission may operate only in certain gears,
or may not shift at all. Vehicle performance may
be severely degraded and the engine may stall.
In some situations, the transmission may not
re-engage if the engine is turned off and
restarted. The Malfunction Indicator Light (MIL)
may be illuminated. A message in the
instrument cluster will inform the driver of the
more serious conditions, and indicate what
actions may be necessary.
In the event of a momentary problem, the
transmission can be reset to regain all forward
gears by performing the following steps:
NOTE:
In cases where the instrument cluster message
indicates the transmission may not re-engage
after engine shutdown, perform this procedure
only in a desired location (preferably, at an
authorized dealer).
1. Stop the vehicle.

2. Shift the transmission into PARK, if
possible. If not, shift the transmission to
NEUTRAL.
3. Push and hold the ignition switch until the engine turns off.
4. Wait approximately 30 seconds.
5. Restart the engine.

6. Shift into the desired gear range. If the problem is no longer detected, the
transmission will return to normal operation.

NOTE:
Even if the transmission can be reset, we
recommend that you visit an authorized dealer
at your earliest possible convenience. An autho -
rized dealer has diagnostic equipment to
assess the condition of your transmission.
If the transmission cannot be reset, authorized
dealer service is required.
Electronic Range Select (ERS) Operation
The ERS shift control allows the driver to
limit the highest available gear when the
transmission is in DRIVE. For example, if you set
the transmission gear limit to FOURTH gear, the
transmission will not shift above FOURTH gear
(except to prevent engine overspeed), but will
shift through the lower gears normally.

You can switch between DRIVE and ERS mode at
any vehicle speed. When the transmission gear
selector is in DRIVE, the transmission will operate
automatically, shifting between all available
gears. Tapping the GEAR – switch (on the
steering wheel) will activate ERS mode, display
the current gear in the instrument cluster, and
set that gear as the top available gear. Once in
ERS mode, tapping the GEAR – or GEAR + switch
will change the top available gear.

4

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